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受賞区分：国内学会・会議・シンポジウム等の賞  受賞国：日本国

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受賞区分：国内学会・会議・シンポジウム等の賞  受賞国：日本国

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受賞区分：国内学会・会議・シンポジウム等の賞 

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受賞区分：国内学会・会議・シンポジウム等の賞 

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受賞区分：国内学会・会議・シンポジウム等の賞 

受賞区分：国内学会・会議・シンポジウム等の賞 

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受賞区分：国内学会・会議・シンポジウム等の賞 

受賞区分：国内学会・会議・シンポジウム等の賞  受賞国：日本国

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie International Edition  

Reversible coordination bonds between boron and heteroatoms endow boron-based π-conjugated frameworks with dynamic functionality, as interconversion between tri- and tetracoordinate boron centers induces pronounced changes in both molecular geometry and electronic structure. In this study, we synthesized a series of chiral boron-embedded polycyclic aromatic hydrocarbons featuring an asymmetric boron center intramolecularly coordinated by a proximal P═O moiety. The resulting tetracoordinate enantiomers exhibit high configurational stability, enabling optical resolution by chiral HPLC. Notably, among the compounds, anthracene-fused boracyclic derivatives display dual circularly polarized luminescence (CPL) arising from excited-state dissociation of the intramolecular P═O⋯B bond, a process whose extent varies depending on the degree of π-extension. In these systems, bond-cleavage converts point chirality in the tetracoordinate state into C−B axial chirality in the tricoordinate state. Taking advantage of the intrinsically superior photophysical properties of tricoordinate boranes, one derivative exhibited CPL with a high quantum yield, while another displayed red-shifted CPL extending to the deep-red region. Furthermore, the dynamic P═O⋯B coordination is highly sensitive to hydrogen-bonding ability and polarity of solvent, thereby giving rise to solvent-dependent dual CPL behavior. These findings establish a new strategy for exploiting reversible coordination in chiral boron-PAHs to access responsive chiroptical functionalities.

DOI： 10.1002/anie.202522746

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Bulletin of the Chemical Society of Japan  

The development of new molecular building blocks for the construction of elaborate molecular assemblies extends the chemical space for materials exploration. Representative organic components for the design of homochiral metal-organic frameworks (MOFs) usually exhibit C <inf>1</inf>- or C <inf>2</inf>-symmetry. Herein, we synthesized a chiral D <inf>2</inf>-symmetric ligand via functionalization of a figure-eight macrocycle, cyclobisbiphenylenecarbonyl (CBBC). This ligand adopts a distinctive concave-type tetradentate coordination geometry, and the resulting MOF, ^CBBCMOF, features a quasi-honeycomb framework enveloped by double-helical ligand assembly. The pore size of the chiral nanochannel exceeds 10 Å, which enables ^CBBCMOF to encapsulate various guest molecules, including aromatic hydrocarbons, alcohols, and dyes. Furthermore, ^CBBCMOF achieves the enantioselective encapsulation of racemic 1,1′-bi-2-naphthol with a high enantiomeric excess (up to 68% ee). Thus, ^CBBCMOF functions as a stationary phase to separate the enantiomers of medium-sized chiral molecules. These results demonstrate that highly symmetric chiral molecules such as CBBC function as an effective building block for the design of advanced porous materials.

DOI： 10.1093/bulcsj/uoag029

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その他リンク： https://academic.oup.com/bcsj/article-pdf/99/2/uoag029/66814538/uoag029.pdf

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie International Edition  

Solvent-solute interactions are utterly important in supramolecular polymers (SPs), yet the high responsivity of SPs to solvent polarity makes it challenging to play on other solvation effects to tune their macroscopic properties in a rational manner. Herein, we report the characterization at various scales of the assembly properties of a C<inf>2</inf>-symmetric benzene-1,3,5-tricarboxamide monomer with two (1S)-methylheptyl moieties and one diphenylphosphino group as lateral chains. Our investigation reveals a highly cooperative structural transition between two SP states, which can exquisitely be tuned by solvents of similar polarities, leading to variation of the transition temperature (T*) over a range of 85 K. The structural transition was detected in 4 pure solvents and 13 toluene/cosolvent mixtures; a fair relationship is determined between T* and the solvent molar volume. The transition is only weakly favored by enthalpy (by ca. 2 kJ.mol⁻¹ at 286 K). However, minimization of the entropic cost leads to a notable increase in the T*. This allows a fine tuning of the thermothickening and catalytic properties of the resulting SPs auguring that solvation, and notably solvation entropy, may constitute an important lever for steering SPs structure and properties.

DOI： 10.1002/anie.202521365

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Japanese Journal of Applied Physics  

Circularly polarized luminescence (CPL) materials with both high photoluminescence quantum yield (PLQY) and large photoluminescence dissymmetry factor (g<inf>lum</inf>) are essential for high-efficiency circularly polarized organic light-emitting diode, because higher PLQY directly improves external quantum efficiency (EQE). However, achieving both high PLQY and strong CPL remains challenging. Here, we report a synergistic strategy combining chiral induction and energy transfer to simultaneously enhance g<inf>lum</inf> and PLQY in red-emissive systems based on the green achiral emitting conjugated polymer. By incorporating chiral inducers and doping the red-emitting energy acceptor, we realized efficient chiral induction and energy transfer, resulting in improved red CPL characteristics. The optimized systems exhibited the highest g<inf>lum</inf> of 0.27 at 615 nm and a PLQYexceeding 0.9, outperforming systems without chiral or energy transfer components. Our findings demonstrate an effective approach to enhancing CPL performance by integrating chiral induction and energy transfer strategies, without synthesizing new molecules.

DOI： 10.35848/1347-4065/ae11bc

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：European Journal of Organic Chemistry  

This study synthesizes cyclic and acyclic aromatic triamides with conjugated systems to establish molecular design guidelines for obtaining reliable circularly polarized luminescence (CPL)-active materials. For the compounds with the phenylacetylene unit, the acyclic derivative shows a single fluorescence at 381 nm, whereas the cyclic ones show dual fluorescence. The long-wavelength emission at 545 nm is significant for the compound with three π-conjugated systems measured at 25 °C. The fluorescence quantum yield and lifetime depend on the number of conjugated systems introduced into the cyclic structure. When the enantiomers of the cyclic compounds is isolated by chiral high-performance liquid chromatography, all of them shows circular dichroism (CD) activity, but only the compound with the three conjugated systems shows CPL with the anisotropy factor g<inf>lum</inf> = 4.0 × 10⁻³. On the other hand, this study also synthesizes two cyclic aromatic triamides with the naphthylacetylene unit and succeeded in optical resolutions. The fluorescence quantum yields (Φ = 0.80 and 0.34) are improved, and a single sky blue emission is observed. The CD and CPL anisotropy factors are larger than those of the phenyl counterpart, and the CPL shows a B<inf>CPL</inf> value of about 30 M⁻¹ cm⁻¹.

DOI： 10.1002/ejoc.202500673

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society (ACS)  

DOI： 10.26434/chemrxiv-2025-m3m0q

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記述言語：英語  

DOI： 10.1002/ejoc.202500673

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Macromolecules  

We report the synthesis of a novel family of one-handed helical ladder polymers incorporating enantiopure 9,9′-spirobifluorene frameworks by an acid-promoted alkyne benzannulation reaction. By varying the para- and meta-substitution patterns of the achiral dialkynylphenylene units of the precursor polymers, we successfully controlled both the helical geometry (helical tube with a helical cavity or helical ribbon with helical grooves) and the helical handedness (right- or left-handed) of the ladder polymers. The resulting polymers exhibited characteristic chiroptical properties due to their unique helical structures and showed complementary enantioseparation capabilities for a series of hydrophobic racemic compounds with point, spiro, axial, planar, and helical chiralities, as well as a chiral metal complex when used as chiral stationary phases for high-performance liquid chromatography. The helical cavity and grooves of the para- and meta-phenylene-embedded helical ladders serve as chiral recognition sites, respectively. These results highlight the potential of spiro-conjugated helical ladder polymers as advanced chiral materials for enantioseparation technologies. In addition, we succeeded in the first direct observation of the periodic helical structure of the meta-phenylene-embedded ladder polymer by high-resolution atomic force microscopy.

DOI： 10.1021/acs.macromol.5c00677

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Dalton Transactions  

Pyridine-functionalized cyclic aromatic triamide (C3A-1EPy) was synthesized by Stille cross-coupling reaction and the chiroptical properties of the separated enantiomers were investigated using CD and CPL spectra. Two copper coordination polymeric complexes (C3A-CuP A and C3A-CuP B) obtained by reacting C3A-1EPy with CuI and Cu<inf>2</inf>I<inf>2</inf>(PPh<inf>3</inf>)<inf>3</inf> were characterized by elemental analysis and MAS ³¹P NMR as well as XPS spectra. Although TADF and CPL were not achieved, room-temperature red phosphorescence was observed at 641 and 630 nm in powder state, and it was found that the emission behavior (wavelength, quantum yield, and lifetime) of C3A-CuP B depends on the optical purity of the ligand.

DOI： 10.1039/d5dt00369e

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry A European Journal  

The scalable synthesis of figure-eight π-systems is challenging for the conventional bottom-up approach. We have recently reported that the oxidative inner-bond cleavage of commercially available dibenzo[g,p]chrysene efficiently furnishes a figure-eight π-acceptor, cyclobisbiphenylenecarbonyl (CBBC), in large quantity. Furthermore, its donor–acceptor-type derivative with four N-carbazolyl substituents at the meta-positions of the carbonyl groups exhibited thermally activated delayed fluorescence (TADF) and circularly polarized luminescence (CPL) with a high |g<inf>CPL</inf>| value of 1.0×10⁻². Herein, we synthesized nine donor–acceptor-type CBBC derivatives by changing the donor substituents and their positions. Compared to previously reported carbazole-substituted CBBC, tetramethylcarbazole- and 9,10-dihydro-9,9-dimethylacridine-substituted derivatives exhibited enhanced emission quantum yields and accelerated reverse intersystem crossing. The functionalization of the para-positions of the carbonyl groups resulted in better tunability of emission colors rather than meta-functionalization, whose color variation ranges from light blue to red. The incorporation of bulky substituents at the meta-positions of the carbonyl groups induced the conformational change to a distorted ring structure. Investigation of the substituent effect on the chiroptical properties revealed that the introduction of less bulky donor units such as carbazole at the meta-positions of the carbonyl groups is effective in achieving high |g<inf>CPL</inf>| values.

DOI： 10.1002/chem.202404194

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担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Yuki Gosei Kagaku Kyokaishi Journal of Synthetic Organic Chemistry  

Biomacromolecules, such as DNA and proteins, form characteristic secondary structures, represented by α -helix and β -sheets, which are further assembled into tertiary and quaternary structures through specific intra- and intermolecular interactions. Such higher-order structures play a key role in the expression of the sophisticated biological functions. While advances in polymerization technologies have made it possible to precisely control the primary structures of synthetic polymers, the design and construction of higher-order structures, even secondary structures, remains a major challenge in polymer science. Recently, the author's group has developed a novel synthetic methodology called “defect-free ladderization” and combined it with “chiral molecular design” to realize the tailored construction of diverse secondary structures to meet specific functional requirements. In this article, we present our recent results with emphasis on the efficient synthesis of defect-free ladder polymers with specific secondary structures via alkyne benzannulations and the development of functional materials based on the rational design of artificial secondary structures. We anticipate that these results will provide new directions for advancing the field of organic synthesis and polymer science.

DOI： 10.5059/yukigoseikyokaishi.83.395

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie International Edition  

We report the helix-sense-selective memory polymerization (HSMP) of achiral biphenylylacetylenes bearing carboxy and amino pendant groups in the presence of basic and acidic chiral guests in water, respectively. The HSMP proceeds in a highly helix-sense-selective manner driven by noncovalent chiral ionic interactions between the monomers and guests under kinetic control, producing the one-handed helical polymers with a static memory of helicity in one-pot during the polymerization in a very short time, accompanied by amplification of asymmetry. The carboxy-bound helicity-memorized polymer self-assembles into a cholesteric liquid crystal in concentrated water, in which a variety of basic achiral fluorophores further co-assembles to form supramolecular helical aggregates that exhibit an induced circularly polarized luminescence in a color tunable manner.

DOI： 10.1002/anie.202412752

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Chemical Society  

Figure-eight-shaped nonplanar π-systems adopt distinctive chiral D<inf>2</inf>-symmetric structures, which are ideal for realizing efficient circularly polarized luminescence (CPL). However, the short-step and enantioselective synthesis of figure-eight π-systems represents a considerable challenge for the conventional bottom-up synthetic strategy. Herein, we report that the oxidative cleavage of the internal double bond of a commercially available polycyclic aromatic hydrocarbon, i.e., dibenzo[g,p]chrysene (DBC), catalytically affords a figure-eight electron-accepting macrocycle, i.e., cyclobisbiphenylenecarbonyl (CBBC), with high scalability (up to 3.3 g) and excellent enantioselectivity (94% ee). This inner-bond-cleavage approach also applies to larger PAHs, affording highly distorted molecular frameworks that comprise two figure-eight subunits. Furthermore, we demonstrate that the peripheral functionalization of CBBC with carbazole afforded donor-acceptor-type emitter, which shows thermally activated delayed fluorescence and emits CPL with a g value of 1.0 × 10^-2. This g value is ten times higher than those of previously reported chiral TADF-active emitters for circularly polarized organic light-emitting diodes. These results demonstrate that oxidative inner-bond cleavage is a powerful synthetic strategy for creating innovative materials that incorporate molecules with figure-eight structures.

DOI： 10.1021/jacs.4c07985

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACS Applied Materials and Interfaces  

The development of materials with circularly polarized luminescence (CPL) properties is a promising but challenging frontier in advanced materials science. Modulating the chiral properties of chiral polymers has also been a focus of research. Studies have been conducted to control the ground-state chirality of chiral polymers by adjusting the concentration of the chiral dopant. However, the chirality inversion of CPL of fluorescent liquid crystal particles by chiral dopant concentration has not been reported. Here, we report the preparation of fluorescent cholesteric liquid crystal (FCLC) particles that display polarizable structural color and CPL, demonstrating how varying the chiral dopant amount can reverse the CPL direction, leading to systems where the rotation directions of polarizable structural color and CPL either align or differ. This study confirmed the critical role played by the formation of the twist grain boundary phase in inducing the inversion of the ground-state chirality of FCLC particles and, subsequently, triggering the inversion process of CPL chirality. Furthermore, it leverages chiral structural color and fluorescence of FCLC particles to develop a sophisticated dual verification system. This system, utilizing both circularly polarized light and fluorescence, offers enhanced anticounterfeiting protection for high-value items.

DOI： 10.1021/acsami.4c08331

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Communications  

Alkyne cycloisomerization of 2,7,10,15-tetra(ortho-alkynylphenyl)benzo[g,p]chrysene containing bulky 4-alkoxy-2,6-dimethylphenyl groups at the alkyne terminals selectively proceeded at the sterically crowded bay-region. The obtained double helicene adopts a distorted structure with a high racemization barrier due to the intramolecular steric repulsion.

DOI： 10.1039/d4cc01573h

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACS Macro Letters  

This work aims to examine the effect of self-assembly on the chiroptic responses of the achiral block copolymer (BCP) polystyrene-b-poly(ethylene oxide) (PS-b-PEO) associated with chiral luminophores, (R)- or (S)-1,1′-bi-2-naphthol ((R)- or (S)-BINOL), through hydrogen bonding. With the formation of a well-ordered helical phase (H*), significantly induced circular dichroism (ICD) signals for the PEO block in the mixture can be found. Most interestingly, a remarkable amplification with an extremely large dissymmetry factor of luminescence (g<inf>lum</inf>) from 10^-3 to 0.3 (i.e., induced circular polarized luminescence (iCPL) behavior) for the chiral BINOLs in the mixture can be achieved by the formation of the helical phase (H*) via mesochiral self-assembly. As a result, by taking advantage of BCP for mesochiral self-assembly, it is feasible to create a nanostructured monolith with substantial optical activities, offering promising applications in the design of chiroptic devices.

DOI： 10.1021/acsmacrolett.4c00188

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie International Edition  

Synthetic breakthroughs diversify the molecules and polymers available to chemists. We now report the first successful synthesis of a series of optically-pure 2,2′-tethered binaphthyl-embedded helical ladder polymers based on quantitative and chemoselective ladderization by the modified alkyne benzannulations using the 4-alkoxy-2,6-dimethylphenylethynyl group as the alkyne source, inaccessible by the conventional approach lacking the 2,6-dimethyl substituents. Due to the defect-free helix formation, the circular dichroism signal increased by more than 6 times the previously reported value. The resulting helical secondary structure can be fine-tuned by controlling the binaphthyl dihedral angle in the repeating unit with variations in the 2,2′-alkylenedioxy tethering groups by one carbon atom at a time. The optimization of the helical ladder structures led to a strong circularly polarized luminescence with a high fluorescence quantum yield (28 %) and luminescence dissymmetry factor (2.6×10⁻³).

DOI： 10.1002/anie.202318712

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Chemical Society  

Allenes are important building blocks, and derivatization of products via cycloadditions of allenes could become a powerful strategy for constructing carbocyclic and heterocyclic rings. However, the development of catalytic site-selective and enantioselective cycloaddition reactions of allenes still presents significant challenges. Here, we report chiral π-Cu(II)-complex-catalyzed isomerization of N-(3-butynoyl)-3,5-dimethyl-1H-pyrazole to generate N-allenoylpyrazole in situ and subsequent α,β-site-selective and enantioselective [3 + 2], [4 + 2], or [2 + 2] cycloaddition or conjugate addition reactions. The asymmetric environment created by the intramolecular π-Cu(II) interactions provides the corresponding adducts in moderate to high yield with excellent enantioselectivity. To the best of our knowledge, this is the first successful method for chiral-Lewis-acid-catalyzed tandem isomerization/α,β-site-selective and enantioselective cycloaddition or conjugate addition reactions of latent non-γ-substituted allenoyl derivative.

DOI： 10.1021/jacs.3c10820

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Organic Materials  

A series of enantiopure triptycene-based one-handed helical ladder polymers containing π-extended achiral segments with naphthalene, fluorene, and carbazole spacers was synthesized through quantitative and chemoselective ladderization of the corresponding precursor polymers with random-coil conformations. The helical handedness (right- or left-handed) and geometry (loose coil or ribbon) of the resulting ladder polymers were readily modulated by tuning the structure of the achiral spacers despite the incorporation of the same point chirality of the triptycene unit. All the helical secondary structures are stable and robust due to the shape-persistent ladder structures, showing the characteristic and environment-independent chiroptical properties.

DOI： 10.1055/a-2208-4389

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Chemical Society  

Controlling the one-handed helicity in synthetic polymers is crucial for developing helical polymer-based advanced chiral materials. We now report that an extremely small amount of chiral biphenylylacetylene (BPA) monomers (ca. 0.3-0.5 mol %) allows complete control of the one-handed helicity throughout the polymer chains mostly composed of achiral BPAs. Chiral substituents introduced at the 2-position of the biphenyl units of BPA positioned in the vicinity of the polymer backbones contribute to a significant amplification of the helical bias, as interpreted by theoretical modeling and simulation. The helical structures, such as the helical pitch and absolute helical handedness (right- or left-handed helix) of the one-handed helical copolymers, were unambiguously determined by high-resolution atomic force microscopy combined with X-ray diffraction. The exceptionally strong helix-biasing power of the chiral BPA provides a highly durable and practically useful chiral material for the separation of enantiomers in chromatography by copolymerization of an achiral functional BPA with a small amount of the chiral BPA (0.5 mol %) due to the robust helical scaffold of the one-handed helical copolymer.

DOI： 10.1021/jacs.3c09308

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie International Edition  

A series of poly(biarylylacetylene)s (PBAs) bearing axially-chiral (S)-and (R)-pyridyl-N-oxide residues with a methoxy, propoxy, or acetyloxy substituent at the 3-position of the biaryl units was synthesized. All the PBAs formed a preferred-handed helix, while the helical sense preference was varied depending on the substituents despite the same twist-sense of the biaryl units. Among them, the propoxy-bound helical PBA showed an exceptionally high chiral recognition ability as a chiral stationary phase (CSP) for high-performance liquid chromatography (HPLC) and efficiently resolved not only various chiral aromatic alcohols, but also a variety of chiral aliphatic alcohols; the latter still remains difficult to resolve by commercially-available CSPs in HPLC. Such practically-useful both handed helical PBA-based CSPs can be produced from the racemic PBA composed of fully racemic monomer units through deracemization of the biaryl units with a chiral alcohol.

DOI： 10.1002/anie.202306252

DOI： 10.1002/anie.202306252

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その他リンク： https://doi.org/10.1002/anie.202306252

担当区分：最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Communications  

Optically-pure triptycene-based metallomacrocycles are, for the first time, synthesized by the coordination-driven self-assembly of enantiopure triptycene-derived ladder-type bis(benzo[f]isoquinoline) ligands with a cis-platinum(ii) complex. A pair of enantiomeric homochiral metallomacrocycles is also produced by the coordination-driven homochiral self-sorting of the corresponding racemic ligands, which relies on the shape-persistent nature of the ladder-structured ligands.

DOI： 10.1039/d3cc02259e

DOI： 10.1039/D3CC02259E

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その他リンク： http://dx.doi.org/10.1039/D3CC02259E

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Polymer Science  

A series of novel biphenylylacetylene (BPA)-based chiral/achiral copolymers bearing a small amount of configurationally labile optically active [5]helicene pendants (5, 10, and 20 mol%) introduced at the 4′-position of the biphenyl units was synthesized. An almost fully right (P)-handed helical copolymer was obtained when copolymerized with 10 mol% of the (M)-[5]helicene-bound BPA monomer, indicative of a very strong sergeants and soldiers effect. The (M)-helicene units of the copolymers are configurationally labile and gradually racemized over time. However, the copolymer with 10 mol% of the (M)-[5]helicene-bound BPA mostly maintained its preferred-handed helicity even after the pendant helicene units were completely racemized, which can be ascribed to the static memory of the main-chain helicity stabilized by the bulky yet racemic helicene units. Hence, the helicity memory of the corresponding helicene-free homopolymer was lost rapidly. For comparison, an optically inactive copolymer containing 10 mol% of the racemic [5]helicene units was also prepared, and noncovalent helicity induction and subsequent memory of the helicity as well as its helix-memory stability were investigated.

DOI： 10.1002/pol.20220658

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie International Edition  

Fully π-conjugated ladder polymers with a spiral geometry represent a new class of helical polymers with great potential for organic nanodevices, but there is no precedent for an optically active helical ladder polymer totally composed of achiral units. We now report the defect-free synthesis and resolution of a fully π-conjugated helical ladder polymer with a rigid helical cavity, which has been achieved by quantitative and chemoselective acid-promoted alkyne benzannulations of a rationally designed, random-coil achiral polymer followed by chromatographic enantioseparation. Because of a sufficiently high helix-inversion barrier, the isolated excess one-handed helical ladder polymer with a degree of polymerization of more than 15 showed a strong circular dichroism with a dissymmetry factor of up to 1.7×10⁻² and is thermally stable, maintaining its optical activity in solution even at 100 °C, as well-supported by molecular dynamics simulation.

DOI： 10.1002/anie.202301962

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie International Edition  

We report the unprecedented sergeants and soldiers (S&S)-type remote control of one-handed helicity in copolymers of chiral/achiral biphenylylacetylenes bearing amphiphilic oligo(ethylene glycol) (OEG) side chains. A small amount of chiral binaphthyl residues (≤10 mol %) introduced at the terminal of the achiral OEG spacers as many as 80 bonds away from the polymer backbones induced a complete one-handed helix in water through preferential intramolecular encapsulation of the binaphthyl groups within a cavity of the copolymers. A fully one-handed helix can be induced virtually independent of the OEG spacer length and concentrations. At a specific spacer length, however, its helix-sense was inverted. The copolymers also form an excess one-handed helix in organic solvents in an OEG spacer-length dependent manner, yet far from the polymer backbones. We show the superiority of the present covalent-bond driven S&S-type remote helicity control over the corresponding noncovalent helicity induction approach.

DOI： 10.1002/anie.202301127

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie International Edition  

Enantiopure [6]helicene containing an embedded seven-membered ring and carbo[7]helicene (>99 % ee) with opposite helicity were simultaneously and quantitatively (>99 %) synthesized with a perfect stereospecificity through stepwise acid-promoted intramolecular alkyne annulations of doubly axial-chiral cyclization precursors. The helical handedness of the [6]- and [7]helicenes was fully stereocontrolled by the doubly axial chirality of the precursors as a result of complete axial-to-helical chirality transfer. The cyclizations proceeded in a stepwise manner; the first six-membered ring formation was followed by the kinetically controlled seven- or six-membered ring formation with or without helix-inversion of a [4]helicene intermediate generated during the first cyclization step, thus quantitatively producing enantiopure circularly polarized luminescent [6]- and [7]helicenes with opposite helicity.

DOI： 10.1002/anie.202301836

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担当区分：最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie International Edition  

Defect-free one-handed contracted helical tubular ladder polymers with a π-electron-rich cylindrical helical cavity were synthesized by alkyne benzannulations of the random-coil precursor polymers containing 6,6′-linked-1,1′-spirobiindane-7,7′-diol-based chiral monomer units. The resulting tightly-twisted helical tubular ladder polymers showed remarkably high enantioseparation abilities toward a variety of chiral hydrophobic aromatics with point, axial, and planar chiralities. The random-coil precursor polymer and analogous rigid-rod extended helical ribbon-like ladder polymer with no internal helical cavity exhibited no resolution abilities. The molecular dynamics simulations suggested that the π-electron-rich cylindrical helical cavity formed in the tightly-twisted tubular helical ladder structures is of key importance for producing the highly-enantioseparation ability, by which chiral aromatics can be enantioselectively encapsulated by specific π-π and/or hydrophobic interactions.

DOI： 10.1002/anie.202218297

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Macromolecules  

A series of cis-poly(biphenylylacetylene) (PBPA) derivatives bearing chiral and achiral pendant groups at the 4′-position of the biphenyl units through an amide (-NHCO-) or carbamate (-NHCOO-) linker were synthesized by polymerization of the corresponding biphenylylacetylene (BPA) monomers that can be readily prepared in one step from a novel amino-functionalized BPA. An excess one-handed helix induction in the PBPAs through covalent and noncovalent chiral interactions and their chiral recognition abilities when used as chiral stationary phases for high-performance liquid chromatography were investigated. PBPAs bearing optically pure l-amino acid residues showed unique two-state helical conformational changes between the extended and contracted helices regulated by the solvent-mediated on/off switching of the intramolecular hydrogen-bonding formations between the pendants or at each pendant. The chiral recognition abilities of the helical PBPAs were significantly influenced by the kinds of the pendant l-amino acid residues. The preferred-handed contracted helical PBPA carrying an l-leucine-derived pendant showed an excellent chiral resolving power toward various racemic compounds including axially and point chiral compounds and chiral metal complexes. The elution orders of some racemates were completely reversed when its helical conformation was changed to the extended helix. On the other hand, the trans-enriched nonhelical l-leucine-bound PBPA derived from its preferred-handed cis-helical PBPA and achiral pendant-bound cis-helical PBPAs induced by noncovalent chiral interactions and subsequent static memory of the helicity showed a poor and no chiral recognition, respectively.

DOI： 10.1021/acs.macromol.2c01362

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACS Macro Letters  

A dynamically racemic helical copolymer composed of an achiral biphenylylacetylene (BPA) bearing methoxymethoxy groups at the 2,2′-positions and 1 mol % of an achiral BPA carrying 2-carboxy-2′-methoxymethoxy groups at the biphenyl pendants was found to fold into an excess one-handed helix with significant amplification of the helicity in the presence of a small amount of optically active amines. The induced macromolecular helicity was retained ("memorized") after removal of the chiral amines. The copolymer had a significant sensitivity for detecting the chirality of chiral amines with a sensitivity more than 10000-fold higher than that of the corresponding homopolymers with no carboxy group, thus showing Cotton effects even in the presence of a 0.01 equiv of an optically active amine. The effects of the substituents at the 4′-position of the biphenyl pendants of the copolymers and the structures of the chiral amines on the macromolecular helicity induction were also investigated.

DOI： 10.1021/acsmacrolett.2c00136

DOI： 10.1021/acsmacrolett.2c00136

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Natural Sciences  

Abstract: We report the quantitative, chemoselective, and diastereospecific formation of the defect-free C-shaped single and S- and M-shaped consecutively fused double- and triple-expanded homochiral helicenes (all-right (P) or all-left (M) handed), in which two and three expanded helicene subunits were exclusively fused together in a helically winding manner, respectively, through the trifluoroacetic acid-promoted intramolecular multistep cascade alkyne benzannulations of anthracene-based cyclization precursors composed of a large number of complicated dynamic stereoisomers due to axial chirality. The resulting racemic expanded helicenes were all separated into enantiomers by chiral chromatography and showed intense circular dichroism and circularly polarized luminescence (CPL) with the absorption and luminescence dissymmetry factors of up to 1.5 × 10⁻² and 0.94 × 10⁻², respectively. Moreover, the triple-expanded helicene showed the highest CPL brightness (255 M⁻¹·cm⁻¹) among all the reported CPL-active carbo- and heterohelicenes and -helicenoids. The helicity inversion barriers remarkably increased with the increasing number of incorporated helicene subunits, and the racemization of the triple-expanded helicene was completely suppressed even at 80°C, providing the first example of an optically active expanded helicene with a static helical chirality. Key Points: Defect-free synthesis of single-, double-, and triple-expanded helicenes with C-, S-, and M-shaped fully conjugated helical ladder structures, respectively. Quantitative and chemoselective acid-catalyzed diastereospecific multistep cascade cyclizations. Circularly polarized luminescence of configurationally stable optically pure expanded helicenes.

DOI： 10.1002/ntls.20210047

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Chemical Society  

We report unique coordination-driven supramolecular helical assemblies of a series of dirhodium(II) tetracarboxylate paddlewheels bearing chiral phenyl- or methyl-substituted amide-bound m-terphenyl residues with triethylene glycol monomethyl ether (TEG) or n-dodecyl tails through a 1:1 complexation with 1,4-diazabicyclo[2.2.2]octane (DABCO). The chiral dirhodium complexes with DABCO in CHCl3/n-hexane (1:1) form one-handed helical coordination polymers with a controlled propeller chirality at the m-terphenyl groups, which are stabilized by intermolecular hydrogen-bonding networks between the adjacent amide groups at the periphery mainly via a cooperative nucleation-elongation mechanism as supported by circular dichroism (CD), vibrational CD, and variable-temperature (VT) absorption and CD analyses. The VT visible-absorption titrations revealed the temperature-dependent changes in the degree of polymerization. The columnar supramolecular helical structures were elucidated by X-ray diffraction and atomic force microscopy. The helix sense of the homopolymer carrying the bulky phenyl and n-dodecyl substituents is opposite those of other chiral homopolymers despite having the same absolute configuration at the pendants. A remarkably strong "sergeants and soldiers"(S&S) effect was observed in most of the chiral/achiral copolymers, while the copolymers of the bulky chiral phenyl-substituted dirhodium complexes with n-dodecyl chains displayed an "abnormal"S&S effect accompanied by an inversion of the helix sense, which could be switched to a "normal"S&S effect by changing the solvent composition. A nonracemic dirhodium complex of 20% enantiomeric excess bearing the less bulky chiral methyl substituents with n-dodecyl chains assembled with DABCO to form an almost one-handed helix (the "majority rule"(MR) effect), whereas the three other nonracemic copolymers showed a weak MR effect.

DOI： 10.1021/jacs.1c12652

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chirality  

Two novel poly(biphenylylacetylene)s (PBPAs) bearing achiral alkylphenyl groups at the 4′-position of the biphenyl pendant through ester linkers with different sequences were synthesized by the rhodium-catalyzed polymerization of the corresponding monomers. The influence of the alkylphenyl pendants and the ester sequences on the macromolecular helicity induction and subsequent static helicity memory was investigated. In addition, the chiral recognition ability as chiral stationary phases for high-performance liquid chromatography of the helicity-memorized PBPAs was also examined. Both polymers formed almost perfect right- and left-handed helical conformations through noncovalent chiral interactions with enantiomeric alcohols, and their induced macromolecular helicities were completely retained (“memorized”) after removal of the helix inducer. A PBPA bearing a 4-n-butylphenoxycarbonyl pendant group with a static helicity memory showed a remarkably high chiral recognition ability toward a wide variety of chiral aromatics, including simple point chiral compounds, axially chiral biaryls, a chiral spiro compound, helicenes, and planar chiral cyclophanes, particularly under the reversed-phase conditions.

DOI： 10.1002/chir.23399

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer Journal  

An optically active acylhydrazine-functionalized biphenyl (AHB) bearing L-alanine-derived oligoamide side chains with tris(alkoxy)phenyl residues at the periphery supramolecularly coassembles with its achiral AHB to form a one-dimensional helical nanofiber, in which intermolecular hydrogen bonding between the chiral/achiral oligoamide pendant units result in modest chiral amplification (the sergeants-and-soldiers effect). The chiral and achiral AHBs copolymerize with 2,6-pyridinedicarboxaldehyde to form preferred-handed helical copolymers with amplification of the helical sense excess driven by intramolecular hydrogen bonds.

DOI： 10.1038/s41428-021-00550-7

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Chemical Society  

Any polymers composed of racemic repeating units are obviously optically inactive and hence chiral functions, such as asymmetric catalysis, will not be expected at all. Contrary to such a preconceived notion, we report an unprecedented helical polymer-based highly enantioselective organocatalyst prepared by polymerization of a racemic monomer with no catalytic activity. Both the right- and left-handed helical poly(biarylylacetylene)s (PBAs) composed of dynamically racemic 2-arylpyridyl-N-oxide monomer units with N-oxide moieties located in the vicinity of the helical polymer backbone can be produced by noncovalent interaction with a chiral alcohol through deracemization of the biaryl pendants. The macromolecular helicity and the axial chirality induced in the PBAs are retained ("memorized") after complete removal of the chiral alcohol. Accordingly, the helical PBAs with dual static memory of the helicity and axial chirality show remarkable enantioselectivity (86% ee) for the asymmetric allylation of benzaldehyde. The enantioselectivity is slightly lower than that (96% ee) of the homochiral PBAs prepared from the corresponding enantiopure (R)- and (S)-monomers, but is comparable to that (88% ee) of the helical PBA composed of nonracemic monomers of ca. 60% ee.

DOI： 10.1021/jacs.1c05620

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie International Edition  

We report the unprecedented synthesis of one-handed helical spiro-conjugated ladder polymers with well-defined primary and secondary structures, in which the spiro-linked dibenzo[a,h]anthracene fluorophores are arranged in a one-handed twisting direction, through quantitative and chemoselective acid-promoted intramolecular cyclizations of random-coil precursor polymers composed of chiral 1,1′-spirobiindane and achiral bis[2-(4-alkoxyphenyl)ethynyl]phenylene units. Intense circular dichroism (CD) and circularly polarized luminescence (CPL) were observed, whereas the precursor polymers exhibited negligible CD and CPL activities. The introduction of 2,6-dimethyl substituents on the 4-alkoxyphenylethynyl pendants is of key importance for this simple, quantitative, and chemoselective cyclization. This strategy is applicable to the defect-free precise synthesis of other varieties of fully π-conjugated molecules and coplanar ladder polymers that have not been achieved before.

DOI： 10.1002/anie.202102885

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Synthesis Germany  

A new family of emissive donor-acceptor-donor (D-A-D) compounds has been developed by introducing two electron donors into the 7,8-diaza[5]helicene core as a novel helical electron acceptor. The X-ray crystallographic analyses revealed the uniquely twisted and helical structures of these compounds in the solid states. Notably, some D-A-D compounds developed herein display distinct mechanochromic luminescence (MCL) in the solid state, and a D-A-D helicene shows circularly polarized luminescence (CPL) with a relatively high luminescence dissymmetry factor g <inf>lum</inf>of ca. 10 ^-3. Time-resolved spectroscopic analysis revealed the aspects of thermally activated delayed fluorescence characters of the helicenes. Furthermore, the emissive helicenes were applied to organic light-emitting diodes as emitters.

DOI： 10.1055/a-1343-5810

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry an Asian Journal  

A series of multiple helicenes was simultaneously synthesized in one step by intramolecular cyclization of a single chrysene derivative containing two 2-[(4-alkoxyphenyl)ethynyl]phenyl units accompanied by rearrangements of the aryl pendants. The electrophile-induced double cyclization with or without aryl migrations proceeded efficiently under acidic conditions to afford annulative π-extension of the chrysene units and produced quadruple (QH-2), triple (TH-2), and double (DH-2) helicenes containing [4]- and/or [5]helicene frameworks with dynamic and/or static helicene chirality in one step. Three multiple helicenes’ structures were determined by X-ray crystallography and/or density functional theory calculations. The multiple TH-2 and DH-2 helicenes were separated into enantiomers because of the stable one and two [5]helicene moieties, respectively, and showed intense circular dichroism and circularly polarized luminescence. Although QH-2, which comprises four [4]helicene subunits, was not resolved into enantiomers, the TH-2 enantiomers were further separated into a pair of diastereomers at low temperature resulting from their substituted [4]helicene chirality.

DOI： 10.1002/asia.202100035

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Chemical Society  

A stimuli-responsible reversible structural transformation is of key importance in biological systems. We now report a unique water-mediated reversible transformation among three discrete double-stranded dinuclear titanium(IV) achiral meso-and chiral rac-helicates linked by a mono(μ-oxo) or a bis(μ-hydroxo) bridge between the titanium ions through hydration/dehydration or its combination with a water-mediated dynamic cleavage/re-formation of the titanium-phenoxide (Ti-OPh) bonds. The bis(μ-hydroxo) bridged titanium(IV) meso-helicate prepared from two tetraphenol strands with titanium(IV) oxide was readily dehydrated in CD3CN containing a small amount of water upon heating, accompanied by Ti-OPh bond cleavage/re-formation catalyzed by water, resulting in the formation of the mono(μ-oxo)-bridged rac-helicate, which reverted back to the original bis(μ-hydroxo)-bridged meso-helicate upon hydration in aqueous CD3CN. These reversible transformations between the meso-and rac-helicates were also promoted in the presence of a catalytic amount of an acid, which remarkably accelerated the reactions at lower temperature. Interestingly, in anhydrous CD3CN, the bis(μ-hydroxo)-bridged meso-helicate was further slowly converted to a different helicate, while its meso-helicate framework was maintained, namely the mono(μ-oxo)-bridged meso-helicate, through dehydration upon heating and its meso to meso transformation was significantly accelerated in the presence of cryptand[2.2.1], which contributes to removing Na+ ions coordinated to the helicate. Upon cooling, the backward meso to meso transformation took place via hydration. Hence, three different, discrete double-stranded chiral rac-and achiral meso-Titanium(IV) helicates linked by a mono(μ-oxo) or a bis(μ-hydroxo) bridge were successfully generated in a controllable manner by a change in the water content of the reaction media.

DOI： 10.1021/jacs.0c13351

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie International Edition  

A racemic monomer-based optically inactive polyacetylene folds into a one-handed helix assisted by a nonracemic alcohol, which can separate various enantiomers as a chiral stationary phase in chromatography. The chiral-resolving power is virtually identical to that of the enantiopure monomer-based one-handed helical polyacetylene. Because of its unique static memory of the induced helicity, the original racemic polyacetylene expresses an auto-evolution of its helical handedness over time, and at the same time, chirality of the nonracemic alcohol is discriminated accompanied by successive enhancement of its optical purity enantioselectively adsorbed on the helical polyacetylene owing to the chiral filter effect as directly monitored by NMR, which contributes to further enhancing the helix-sense-excess of the helical polyacetylene.

DOI： 10.1002/anie.202014946

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Cellulose  

Abstract: For efficient enantioseparation, eight organic–inorganic hybrid bead-type chiral packing materials (CPMs) with high organic contents have been developed using cellulose tris(3,5-dimethylphenylcarbamates) bearing small amount of 3-(triethoxysilyl)propyl groups and tetraethyl orthosilicate by a modified Stöber process in the basic condition. The hybrid beads could be formed more efficiently in the basic condition without using surfactant, compared to that in the acidic condition. The preparation conditions, including type and amount of catalyst, amount of water and temperature, significantly affected the organic contents and morphology of the hybrid CPMs. Their chiral recognition properties were then examined by high-performance liquid chromatography. The obtained hybrid CPMs with a higher organic content possessed better enantioseparation ability than the traditional CPMs and previous analogue derived from the acidic condition. For some racemates, the hybrid CPMs exhibited even higher enantioselectivity than the commercial Chiralpak IB N, which is one of the most powerful immobilized-type CPMs and prepared from cellulose tris(3,5-dimethylphenylcarbamate). Graphic abstract: [Figure not available: see fulltext.].

DOI： 10.1007/s10570-020-03514-x

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Chemical Society  

We report a highly enantio- and helix-sense-selective encapsulation of helical poly(lactic acid)s (PLAs) through a unique "helix-in-helix"superstructure formation within the helical cavity of syndiotactic poly(methyl methacrylate) (st-PMMA) with a one-handed helicity memory, which enables the separation of the enantiomeric helices of the left (M)- and right (P)-handed-PLAs. The M- and P-helical PLAs with different molar masses and a narrow molar mass distribution were prepared by the ring-opening living polymerization of the optically pure l- and d-lactides, respectively, followed by end-capping of the terminal residues of the PLAs with a 4-halobenzoate and then a C60 unit, giving the C60-free and C60-bound M- and P-PLAs. The C60-free and C60-bound M- and P-PLAs formed crystalline inclusion complexes with achiral st-PMMA accompanied by a preferred-handed helix induction in the st-PMMA backbone, thereby producing helix-in-helix superstructures with the same-handedness to each other. The induced helical st-PMMAs were retained after replacement with the achiral C60, indicating the memory of the induced helicity of the st-PMMAs. Both the C60-free and C60-bound helical PLAs were enantio- and helix-sense selectively encapsulated into the helical hollow space of the optically active M- and P-st-PMMAs with the helicity memory prepared using chiral amines. The M- and P-PLAs are preferentially encapsulated within the M- and P-st-PMMA helical cavity with the same-handedness to each other, respectively, independent of the terminal units. The C60-bound PLAs were more efficiently and enantioselectively trapped in the st-PMMA compared to the C60-free PLAs. The enantioselectivities were highly dependent on the molar mass of the C60-bound and C60-free PLAs and significantly increased as the molar mass of the PLAs increased.

DOI： 10.1021/jacs.0c11204

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry Letters  

The deracemization reaction of a racemic double-stranded spiroborate helicate containing a bisporphyrin unit in the middle assisted by optically-active guests efficiently proceeded even below room temperature in the presence of a catalytic amount of strong acids that triggered the partial BO bond cleavage/ reformation of the spiroborate groups, affording an optically-active helicate with a high enantioselectivity up to 93% ee.

DOI： 10.1246/cl.200352

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Giant  

A series of amphiphilic biphenylylacetylene-based homo- and copolymers (PBPAs) carrying chiral and/or achiral oligo(ethylene glycol) pendants at the 4′-position of the biphenyl units were synthesized and the amplification of the macromolecular helicity through noncovalent and/or covalent chiral interactions followed by the memory of the helicity were investigated in both water and organic solvents. The macromolecular helicity was efficiently induced in the homopolymers of achiral monomers through specific encapsulation of a catalytic amount of hydrophobic chiral guests in water and their induced helicities were stably memorized in water after complete removal of the optically-active guests, while an excess helical sense was not biased at all in the homopolymers in toluene. One-handed macromolecular helicities were also efficiently induced in the chiral homopolymers through chiral information transfer from covalently linked optically-active pendants with a point chirality to biphenyl units with a dynamic axial chirality, whose helical senses were almost perfectly inverted in water and organic solvents. The achiral/chiral copolymers displayed a unique bidirectional (P and M) strong chiral amplification of the macromolecular helicity in water and toluene assisted by the solvent-induced helix-inversion, and their macromolecular helicities were further enhanced or inverted through encapsulation of a catalytic amount of enantiomeric alcohols in water, which could be further memorized in water after removing the encapsulated guests. We also demonstrated that the left- and right-handed circularly polarized lights could be generated through chirality transfer from the one-handed helical polymers with a macromolecular helicity memory, consisting entirely of achiral monomer units, to an achiral fluorescent dye in the blended films. Importantly, the resulting luminescence dissymmetry factors (ca. 2 × 10^–3) were virtually the same as those of chiral homopolymers composed of the optically-pure repeating units.

DOI： 10.1016/j.giant.2020.100016

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Chemical Society  

We report the synthesis of one-dimensional supramolecular polymers composed of one-handed helical macromolecules bearing fluorescent pendant groups and the generation of circularly polarized light on the basis of hierarchical chiral amplification starting from a tiny amount of chiral substituent. Copolymerization of benzo[1,2-b:4,5-b′]dithiophene-appended achiral/chiral isocyanides (99:1, mol/mol) with a solid-state photoluminescence feature afforded submicrometer supramolecular fibers, in which almost perfect single-handed helical polyisocyanides were noncovalently connected end to end. The resulting helical supramolecular polymers were further helically assembled to form a cholesteric liquid crystal film with an intense circularly polarized luminescence (CPL) signal. Surprisingly, the supramolecular system containing only 0.01 mol % of the chiral monomer unit also emitted the observable circularly polarized light owing to multiple chiral amplification from an infinitesimal point chirality to helical chirality and then to supramolecular chirality. Furthermore, chiral information was efficiently transferred from the helically assembled supramolecular system containing 1 mol % of the chiral unit to achiral dye molecules blended in the film, allowing full-color tunable induced CPL with luminescence dissymmetry factors greater than 1.0 × 10^-2. This unprecedentedly strong chiral amplification enables the creation of helical supramolecular polymers and chirally assembled systems with various chiral functions based solely on an infinitesimal chiral source.

DOI： 10.1021/jacs.9b13584

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Macromolecules  

A series of dynamic helical homo- A nd copolymers of chiral and/or achiral biphenylylacetylenes (PBPAs) bearing achiral methoxymethoxy or acetyloxy groups at the 2,2′-positions along with a chiral or achiral alkyl ether or alkoxy carbonyl group at the 4′-position of the biphenyl pendants were synthesized. The effects of the chiral/achiral substituents at different positions on their helical structures and amplification of the helicity through covalent and further noncovalent chiral interactions followed by the memory of the helicity were investigated. The chiral homopolymers formed a preferred-handed helical structure as revealed by their circular dichroism (CD) spectra, whose Cotton effect signs and intensities were significantly dependent on the chiral/achiral pendant groups introduced at the 2,2′,4′-positions of the biphenyl units as well as the solvents and temperatures, while the corresponding poly(phenylacetylene)s carrying the identical chiral substituents exhibited negligible CDs. Among the chiral homopolymers, a PBPA bearing the 2,2′-methoxymethoxy and 4′-chiral alkyl ether groups showed a unique helix-inversion/switching in aliphatic hydrocarbons according to whether they are cyclic or acyclic. The chiral/achiral copolymers displayed a moderate amplification of the helicity due to the chiral units covalently bonded to the pendants (the sergeants-and-soldiers effect). The macromolecular helicity of the copolymers with imperfect or no helical sense excesses was, however, significantly enhanced to the almost completely one-handed helices or inverted to the opposite ones through noncovalent chiral interactions with enantiomeric alcohols, which could be further memorized after the complete removal of the chiral alcohols.

DOI： 10.1021/acs.macromol.9b02727

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer Chemistry  

A series of poly(biphenylylacetylene)s (PBPAs) bearing various functional groups at the 4′-position of the biphenyl pendants were synthesized. The effects of the pendant functional groups on their macromolecular helicity induction and subsequent memory behaviors as well as their chiral recognition abilities as chiral stationary phases (CSPs) for high-performance liquid chromatography (HPLC) were investigated. Both the macromolecular helicity and the pendant axial chirality of the PBPAs bearing ester, acyloxy or carbamate groups induced by noncovalent interactions with an optically active alcohol were more stably memorized compared to those induced in the PBPAs bearing ether pendant groups when the optically active alcohol was completely removed. The PBPAs with a macromolecular helicity memory showed different chiral recognition abilities toward various racemates depending on the difference in the achiral pendant functional groups when used as CSPs for HPLC under normal phase conditions. The PBPA bearing carbamate pendants exhibited an excellent chiral recognition ability and resolved many racemates including axially chiral compounds and metal acetylacetonate complexes. Since the obtained PBPAs are soluble in the chiral alcohol, it was almost impossible to switch their enantioselectivities by treatment of the coated-type CSPs with a solution of the chiral alcohol in the column. By immobilizing the PBPA chains onto silica gel, the reversible control of the macromolecular helicity in the column could be achieved through alternate column treatment with a solution containing the (R)- or (S)-enantiomer of the chiral alcohol, thereby enabling the repeated switching of the enantiomer elution order.

DOI： 10.1039/c9py01425j

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Organic and Biomolecular Chemistry  

Catalytically active chiral π-conjugated polymers (poly-1(NO)<inf>r</inf>) bearing pyridine N-oxide pendants were synthesized by ternary copolymerization of a d-glucose-bound diethynyl compound with two types of thieno[3,4-b]thiophene comonomer, one of which contained a pyridine N-oxide group. When the pyridine N-oxide content in the copolymer was 10 mol% (poly-1(NO)<inf>0.10</inf>), the polymer backbone formed a one-handed helical structure in acetonitrile. Pyridine N-oxide pendants arranged inside the helical cavity of poly-1(NO)<inf>0.10</inf> exhibited catalytic activity for the asymmetric allylation of benzaldehydes, producing the corresponding allyl alcohols with up to 43% ee.

DOI： 10.1039/c9ob01828j

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Polymer Science Part A Polymer Chemistry  

Novel poly(biphenylylacetylene) derivatives carrying different types of pyridine N-oxide units with a bulky or less-bulky substituent at a different position as the functional pendant groups (poly-2a and poly-2b) were synthesized by the rhodium-catalyzed polymerization of the corresponding monomers. The influence of the steric environment around the catalytically active pyridine N-oxide sites on the helicity induction and its static memory as well as the asymmetric catalytic activities of the resulting helical polymers with a macromolecular helicity memory was investigated. The polyacetylenes formed an excess one-handed helical conformation upon noncovalent interactions with optically active alcohols and the induced macromolecular helicities of the polyacetylenes were efficiently memorized after the removal of the chiral inducers. Poly-2b with the macromolecular helicity memory showed an enantioselectivity for the catalytic asymmetric allylation of benzaldehydes, producing optically active allyl alcohols, although their enantioselectivities were low. On the other hand, poly-2a exhibited a negligible catalytic activity probably due to the bulky substituent at the o-position of the pyridine N-oxide residues, while poly-2a underwent a unique helix-inversion with the increasing concentration of chiral alcohols and the opposite helicity of poly-2a was further successfully memorized. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2481–2490.

DOI： 10.1002/pola.29501

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その他リンク： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/pola.29501

担当区分：最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Communications  

A pair of novel optically active triptycene-based molecules ((R,R)-1 and (S,S)-1) containing two hexabenzocoronene moieties were synthesized and their optical and chiroptical properties were investigated. Optically active 1 emitted preferred-handed circularly polarized light upon UV irradiation, with the luminescence dissymmetry factors found to be approximately 1.0 × 10^-3. Based on a comparative study using the analogous triptycene derivative with two hexaphenylbenzene units (2), which was the key precursor of 1, the ladder-type rigid structure with an asymmetrically bent geometry was important for optically active 1 to exhibit circularly polarized luminescence (CPL). We also showed that rac-1 undergoes conglomerate crystallization, which allowed CPL to be produced by a random selection of crystals prepared from rac-1.

DOI： 10.1039/c9cc06025a

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担当区分：最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Chemical Society  

Living systems achieve sophisticated functions using supramolecular protein assemblies, in which the protein building blocks possess a specific secondary structure and are noncovalently arranged in a preprogrammed manner. Herein, we demonstrate the one-step synthesis of one-dimensional macromolecular assemblies by simply mixing a glycine-based isocyanide with a nickel catalyst, in which helical constituent polymers are linked end-to-end through multiple hydrogen bonds. The applicable scope of this approach is not confined to a particular monomer bearing a specially designed pendant, but covers a wide range of glycine-based isocyanides with or without aromatic and other functional groups. Surprisingly, copolymerization with an analogous chiral isocyanide (1 mol %) afforded an almost perfect one-handed helical supramolecular fiber owing to intramolecular/intermolecular dual chiral amplifications. The simplicity and broad applicability of this approach, which can also afford exquisite chiral amplification, enable the creation of a wide variety of functional supramolecular assemblies and provide access to new supramolecular materials.

DOI： 10.1021/jacs.9b07417

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jhazmat.2019.120816

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c9sc00342h

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/jacs.8b13865

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c8py01436a

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c7py01867c

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.macromol.8b00229

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acsmacrolett.8b00106

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Chemical Society  

We report the first direct chirality sensing of a series of chiral hydrocarbons and isotopically chiral compounds (deuterated isotopomers), which are almost impossible to detect by conventional optical spectroscopic methods, by a stereoregular polyacetylene bearing 2,2′-biphenol-derived pendants. The polyacetylene showed a circular dichroism due to a preferred-handed helix formation in response to the hardly detectable hidden chirality of saturated tertiary or chiroptical quaternary hydrocarbons, and deuterated isotopomers. In sharp contrast to the previously reported sensory systems, the chirality detection by the polyacetylene relies on an excess one-handed helix formation induced by the chiral hydrocarbons and deuterated isotopomers via significant amplification of the chirality followed by its static memory, through which chiral information on the minute and hidden chirality can be stored as an excess of a single-handed helix memory for a long time.

DOI： 10.1021/jacs.7b10981

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1295/koron.2018-0008

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c8ra04434a

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Macromolecules  

DOI： 10.1021/acs.macromol.7b01955

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c7ob02046e

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Health and Social Care in the Community  

Studies of aspirational ideals of medical care generally focus on patients rather than on ordinary people receiving or not receiving medications at the time of interview. The literature has not accurately conveyed the distinct ideals in individual communities or undertaken inter-regional comparisons. This current qualitative study focused on ideal medical care as perceived by residents of distinct Japanese communities in their everyday lives. Between December 2011 and November 2012, one-on-one and group-based semi-structured interviews were conducted with 105 individuals, each of whom had continuously lived for 20 years or more in one of the four types of communities classified as either ‘metropolitan area’, ‘provincial city’, ‘mountain/fishing village’ or ‘remote island’ in Japan. Interviews were transcribed from digital audio recordings and then analysed (in tandem with non-verbal data including participants’ appearances, attitudes and interview atmospheres) using constructivist grounded theory, in which we could get the voice and mind of the participant concerning ideal medical care. The common themes observed among the four community types included ‘peace of mind because of the availability of medical care’ and ‘trust in medical professionals’. Themes that were characteristic of urban communities were the tendency to focus on the content of medical care, including ‘high-level medical care’, ‘elimination of unnecessary medical care’ and ‘faster, cheaper medical care’, whereas those that were characteristic of rural communities were the tendency to focus on lifestyle-oriented medical care such as ‘support for local lifestyles’, ‘locally appropriate standards of medical care’ and ‘being free from dependence on medical care’. The sense of ideal medical care in urban communities tended to centre around the satisfaction with the content of medical care, whereas that in rural communities tended to centre around the ability to lead a secure life. By considering medical care from the geographical point of view, we found out the significant relationship between communities and perceptions of medical care ideals.

DOI： 10.1111/hsc.12271

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1246/bcsj.20170122

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c7py00804j

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：European Physical Journal C  

During 2015 the ATLAS experiment recorded 3.8fb-1 of proton–proton collision data at a centre-of-mass energy of 13TeV. The ATLAS trigger system is a crucial component of the experiment, responsible for selecting events of interest at a recording rate of approximately 1 kHz from up to 40 MHz of collisions. This paper presents a short overview of the changes to the trigger and data acquisition systems during the first long shutdown of the LHC and shows the performance of the trigger system and its components based on the 2015 proton–proton collision data.

DOI： 10.1140/epjc/s10052-017-4852-3

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.polymer.2017.04.032

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

Chiral sensing using fluorescent responses as output signals is an attractive technique for enantiodifferentiation in terms of its rapidity, high sensitivity, simplicity and high-throughput ability. However, because the reported sensors can only be applied to a limited type of chiral molecule (mainly compounds with a chiral center), it is still a great challenge to develop a powerful fluorescent sensor applicable to various types of chirality. Herein, we synthesized a novel chiral fluorescent sensor (Ce-3) containing a benzo [1,2-b: 4,5-b'] dithiophene-based p-conjugated group as a fluorescent signaling unit through a two-step polymer reaction, including carbamoylation and cross-coupling reactions, using microcrystalline cellulose as a starting material. The enantioselective fluorescence response of this modified cellulose to aromatic nitro compounds was investigated in solution and in the solid state. Ce-3 exhibited enantioselective fluorescence quenching for a wide range of aromatic nitro compounds with central, axial and planar chirality. Visual chiral detection based on a change of the visible emission color was also achieved with Ce-3 in conjunction with anthracene as an achiral fluorescent dye. A corresponding model molecule did not show any marked sensing ability, suggesting that the regular higher-order structure of Ce-3 plays a key role in this efficient chiral sensing.

DOI： 10.1039/c7py00285h

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1038/pj.2016.123

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chirality  

Novel poly(biphenylylacetylene) derivatives bearing two acetyloxy groups at the 2- and 2′-positions and an alkoxycarbonyl group at the 4′-position of the biphenyl pendants (poly-Ac's) were synthesized by the polymerization of the corresponding biphenylylacetylenes using a rhodium catalyst. The obtained stereoregular (cis-transoidal) poly-Ac's folded into a predominantly one-handed helical conformation accompanied by a preferred-handed axially twisted conformation of the biphenyl pendants through noncovalent interactions with a chiral alcohol and both the induced main-chain helicity and the pendant axial chirality were maintained, that is, memorized, after complete removal of the chiral alcohol. The stability of the helicity memory of the poly-Ac's in a solution was lower than that of the analogous poly(biphenylylacetylene)s bearing two methoxymethoxy groups at the 2- and 2′-positions of the biphenyl pendants (poly-MOM's). In the solid state, however, the helicity memory of the poly-Ac's was much more stable and showed a better chiral recognition ability toward several racemates than that of the previously reported poly-MOM when used as a chiral stationary phase for high-performance liquid chromatography. In particular, the poly-Ac-based CSP with a helicity memory efficiently separated racemic benzoin derivatives into enantiomers.

DOI： 10.1002/chir.22687

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c6ra28659c

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c7ra90032e

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Reviews  

In this review, we describe the recent advances in supramolecular helical assemblies formed from chiral and achiral small molecules, oligomers (foldamers), and helical and nonhelical polymers from the viewpoints of their formations with unique chiral phenomena, such as amplification of chirality during the dynamic helically assembled processes, properties, and specific functionalities, some of which have not been observed in or achieved by biological systems. In addition, a brief historical overview of the helical assemblies of small molecules and remarkable progress in the synthesis of single-stranded and multistranded helical foldamers and polymers, their properties, structures, and functions, mainly since 2009, will also be described.

DOI： 10.1021/acs.chemrev.6b00354

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/molecules21111487

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/molecules21111518

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1246/cl.160542

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/slct.201600205

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.7567/JJAP.55.03DC10

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3724/SP.J.1123.2015.10037

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c6py01351a

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Computer Science  

Stress-free interaction between humans and robots is necessary to support humans in daily life. In order to achieve this, we anticipate the development of new robots equipped with tactile and vision sensors for receiving human instructions. In this article, we focus on spontaneous movements that do not require training, such as pointing and force adjustment and that are suitable for daily care. These movements, which we call natural instructions, involve the transmission of human instructions to robots. In this experiment, we examine a robot equipped with vision and tactile sensors capable of receiving natural instructions. Our new robot accomplishes a retrieving and passing task using the natural instructions of finger pointing and tapping with the palm.

DOI： 10.3844/jcssp.2016.246.254

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c6py01759b

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c6py00967k

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1038/pj.2015.42

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1246/cl.150299

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/pola.27589

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.polymer.2014.11.033

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c5ra14408f

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Chromatography A  

Polysaccharide-based chiral stationary phases (CSPs) or chiral packing materials (CPMs) have been frequently employed for analyzing and separating various enantiomers by high-performance liquid chromatography (HPLC). The polysaccharide derivatives dissolved in a solvent are usually coated on silica gel to be used as CSPs. This means that some solvents, which can swell or dissolve the derivatives, cannot be used as the eluents in HPLC. In this review, various immobilization methods of the polysaccharide derivatives are described. The immobilization often reduces the chiral recognition ability compared to that of the corresponding coated-type CSPs. This problem can be overcome by the versatility of eluent selection for the immobilized CSPs. Enantioseparations of various racemates on the immobilized commercial columns using the non-standard eluents are briefly summarized.

DOI： 10.1016/j.chroma.2014.06.042

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ma501612e

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.reactfunctpolym.2014.06.001

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nature Chemistry  

In the chromatographic separation of enantiomers the order of elution is determined by the strength of diasteromeric interactions between the components of the mixture and a chiral stationary phase. For analytical purposes, it is ideal to have the minor component elute first, whereas in the preparative mode a faster elution of the major component is desirable. Here we describe a stationary phase constructed from a polyacetylene that bears 2,2â €2-bisphenol-derived side chains in which chirality can be switched in the solid state prior to use. Both the macromolecular helicity of the polymer backbone and the axial chirality of the side chains can be switched in the solid state by interaction with a chiral alcohol, but importantly are maintained after removal of the chiral alcohol because of a memory effect. The chiral stationary phase thus prepared was used to separate the enantiomers of trans-stilbene oxide with the enantiomer elution order determined by the preseparation treatment. © 2014 Macmillan Publishers Limited. All rights reserved.

DOI： 10.1038/NCHEM.1916

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.polymer.2014.03.021

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal on Smart Sensing and Intelligent Systems  

When a human gives an order to a robot, the robot must often use its vision to ascertain the human's indication. In our previous paper, to develop a system where robots precisely receive and obey human orders in daily work spaces, we proposed an experimental system for finger direction recognition (FDR) in 3D space using stereo matching by mounting two cameras on the robot. In this paper, we evaluate this system for FDR in 3D space by performing a series of evaluation experiments using a turntable capable of fixing a hand in a specific finger direction. We estimated various finger directions and distances for two major pointing hand forms (Forms 1 and 2) and evaluated the precision of θ and Φ. We conclude that the θ and Φ estimations are valid because the estimation error is almost within 10 ° when the distance between the camera and object is less than 110 and 80 cm for θ and φ for Forms 1 and 2, respectively. Finally, we applied our FDR system to the communication between a robot and a person by visual and tactile sensations. In the application test, the robot recognized the object at which the person pointed and put it in the person's palm.

DOI： 10.21307/ijssis-2017-640

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.synthmet.2012.07.003

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c2cc00024e

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：2011 IEEE International Conference on Robotics and Biomimetics Robio 2011  

The vision compensates for the limitations of tactile information and tactile sensing, and vice versa. The tactile sensor can obtain geometrical data as real scale, while image data requires calibration to obtain length as a metric unit. Even if stereovision is used, we cannot obtain sufficient precision. In the evaluation test, the robotic hand equipped with tactile sensors traces an object including convex and concave portions to evaluate edge trace precision. Error of distance obtained by the binocular vision is around ± 10 mm when distance between the camera and object is around 600 mm. When the hand-arm robot touches the convex portion of the object, size data obtained by the vision is modified within ± 0.5 mm accuracy. Since the robotic finger is too thick to touch the bottom of the concave, size data of the concave portion obtained by tactile sensing includes relatively large error of around 4 mm. However, the robot finger can follow the contour with ± 0.5 mm accuracy except for the bottom portion. Therefore, vision sensing is not sufficient for precise edge exploration and modification based on tactile sensing is required. © 2011 IEEE.

DOI： 10.1109/ROBIO.2011.6181493

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Israel Journal of Chemistry  

Polysaccharide-based chiral packing materials (CPMs) for high-performance liquid chromatography (HPLC) have been widely used to determine the enantiomeric excess of a wide range of chiral compounds and also to resolve them on an industrial scale. These CPMs have conventionally been prepared by physically coating a chromatographic support with the polysaccharide derivatives. However, solvents that swell or dissolve the polysaccharide derivatives cannot be used as an eluent component because the column performance will be drastically decreased. This restriction on eluent selection is sometimes a serious issue for efficient analytical and preparative enantioseparations. In order to enhance the diversity of the eluent selection, immobilized CPMs, in which the polysaccharide derivatives are immobilized onto chromatographic supports, have been developed since 1987. This review summarizes the various immobilization methods of the polysaccharide derivatives mainly onto silica gel as a chromatographic support. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/ijch.201100025

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.reactfunctpolym.2011.07.010

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ma201501g

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal on Smart Sensing and Intelligent Systems  

This paper describes a hand-arm system equipped with optical three-axis tactile sensors and a binocular vision sensor. The vision compensates for the limitations of tactile information and tactile sensing, and vice versa. The tactile sensor can obtain geometrical data as real scale, while image data requires calibration to obtain length as a metric unit. Even if stereovision is used, we cannot obtain sufficient precision. In the evaluation test, the robotic hand equipped with tactile sensors traces an object including convex and concave portions to evaluate edge trace precision. Error of distance obtained by the binocular vision is around ± 10 mm when distance between the camera and object is around 600 mm. When the hand-arm robot touches the convex portion of the object, size data obtained by the vision is modified within ± 0.5 mm accuracy. Since the robotic finger is too thick to touch the bottom of the concave, size data of the concave portion obtained by tactile sensing includes relatively large error of around 4 mm. However, the robot finger can follow the contour with ± 0.5 mm accuracy except for the bottom portion. Therefore, vision sensing is not sufficient for precise edge exploration and modification based on tactile sensing is required.

DOI： 10.21307/ijssis-2017-454

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Society of Japan  

DOI： 10.1246/bcsj.20110074

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Bulletin of the Chemical Society of Japan  

Poly(p-phenylenevinylene) (PPV) was found to be encapsulated in amylose during the polymerization of the precursor monomer in an aqueous solution. The resulting amylosePPV composite can be further chemically modified by introducing various substituents into the hydroxy groups of the amylose using isocyanates and acetic anhydride. Here we report on the chemical modification of the amylosePPV composite with 3,5-dimethylphenyl isocyanate in order to obtain a novel chiral packing material for resolving enantiomers by high-performance liquid chromatography (HPLC). The obtained 3,5-dimethylphenylcarbamated amylosePPV was soluble in pyridine and exhibited a lyotropic liquid crystalline phase in a concentrated pyridine solution. The chiral recognition ability of the 3,5-dimethylphenylcarbamated amylosePPV was different from that of amylose tris(3,5-dimethylphenylcarbamate) having no PPV rods in the helical cavity of the amylose and can resolve many racemic compounds into enantiomers. Among racemic compounds, cyclic dibenzamide and dibenzanilide derivatives were resolved on the 3,5-dimethylphenylcarbamated amylosePPV better than amylose tris(3,5-dimethylphenylcarbamate). The difference in the enantioseparation abilities of these amylose-based chiral stationary phases for HPLC is discussed based on the difference in their helical structures. © 2011 The Chemical Society of Japan.

DOI： 10.1246/bcsj.20110074

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nature Publishing Group  

DOI： 10.1038/pj.2010.108

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer Journal  

Cellulose derivatives bearing pyridyl and bipyridyl residues were synthesized, and their recognition abilities as chiral stationary phases for high-performance liquid chromatography were evaluated. Compared with cellulose derivatives bearing these residues at the 2-, 3- and 6-positions of a glucose ring, the regioselectively substituted derivatives exhibited relatively high chiral recognition. The recognition ability of the derivatives was significantly influenced by the coordination of a Cu(II) ion to the bipyridyl residues. In addition, the derivatives were also used for ligand-exchange chromatography with an eluent containing a copper salt to directly separate amino acids without derivatization. © The Society of Polymer Science, Japan (SPSJ). All rights reserved.

DOI： 10.1038/pj.2010.108

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry Letters  

Two novel amylose derivatives 2a and 2b bearing A-tertbutylbenzoate at the 2-position and 3,5-dichlorophenylcarbamate/3-(triethoxysilyl)propylcarbamate residues at 3- and 6positions were successfully synthesized and immobilized onto silica gel, and their chiral recognition abilities were evaluated as chiral packing materials (CPMs) for high-performance liquid chromatography. These immobilized CPMs exhibited recognition ability similar to conventional coated CPM, and for some racemates, comparable or better resolutions were observed even compared to commercial immobilized amylose- or cellulosebased columns. © 2010 The Chemical Society of Japan.

DOI： 10.1246/cl.2010.442

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Separation Science  

The 3,5-dimethylphenylcarbamates of cellulose and amylose were effectively immobilized onto plain silica gels as chiral packing materials (CPMs) for HPLC by means of intermolecular polycondensation of triethoxysilyl groups introduced with (3-glycidoxypropyl)-triethoxysilane. The immobilization and chiral recognition abilities of the obtained CPMs prepared with different amounts of (3-glycidoxypropyl)triethoxysilane were investigated. In addition, the solvent compatibilities of the immobilized-type CPMs were examined with eluents containing chloroform and THF. When these eluents were used, for most of the tested racemates, the chiral resolving abilities of the obtained CPMs were improved. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA.

DOI： 10.1002/jssc.200900711

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Chromatography A  

A new class of regioselectively substituted amylose derivatives bearing three different substituents at 2-, 3- and 6-positions, and two different substituents at 2-position and 3-, 6-positions were synthesized by a sequential process based on the esterification of 2-position of a glucose unit. Their chiral recognition abilities were evaluated as chiral stationary phases (CSPs) for high-performance liquid chromatography (HPLC). Each derivative had its own characteristic recognition ability depending on the arrangement of side chains at the three positions. Among the derivatives, amylose 2-(4-t-butylbenzoate) and amylose 2-(4-chlorobenzoate) series exhibited high chiral recognition. Some racemates can be efficiently separated on these derivatives as well as on the amylose tris-3,5-dimethylphenylcarbamate, which is commercially available as Chiralpak AD and one of the most powerful CSPs. The structures of the amylose derivatives were also investigated by circular dichroism spectroscopy. © 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2009.07.027

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Society of Polymer Science, Japan  

DOI： 10.1038/pj.2009.300

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chirality  

A small amount of 4-(trimethoxysilyl)phenyl groups was randomly introduced onto the 3,5-dimethylphenylcarbamates of cellulose and amylose by a onepot method. The obtained derivatives were then effectively immobilized onto silica gel as chiral packing materials (CPMs) for high-performance liquid chromatography through intermolecular polycondensation of the trimethoxysilyl groups. The effects of the amount of 4-(trimethoxysilyl)phenyl groups on immobilization and enantioseparation were investigated. Also, the solvent durability of the immobilized-type CPMs was examined with the eluents containing chloroform and tetrahydrofuran. When these eluents were used, the chiral recognition abilities of the CPMs for most of the tested racemates were improved to some extent depending on the compounds. © 2009 Wiley-Liss, Inc.

DOI： 10.1002/chir.20722

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer Journal  

Novel amylose ester derivatives were synthesized and their chiral recognition abilities as chiral stationary phases for highperformance liquid chromatography were evaluated. Compared with amylose benzoate derivatives, cinnamate derivatives showed a higher chiral recognition ability and some racemates could be efficiently resolved. The recognition abilities of these derivatives varied significantly depending on the types and positions of substituents introduced into the phenyl group. Among the prepared derivatives, the nonsubstituted cinnamate derivative showed a relatively high chiral recognition, and interestingly, its ability was influenced by the preparation conditions of packing materials using silica gel as a support. © The Society of Polymer Science, Japan (SPSJ) All rights reserved.

DOI： 10.1038/pj.2009.300

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担当区分：筆頭著者   記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：Chiral Recognition in Separation Methods Mechanisms and Applications  

Among more than one hundred commercially available CSPs, those based on the phenylcarbamates of polysaccharides including cellulose and amylose have been recognized as the most powerful for the resolution of a wide range of racemates, and nearly 90% of chiral compounds can be resolved at the analytical level using the polysaccharide-based CSPs. Although the qualitative understanding of the chiral recognition mechanism of polysaccharide-based CSPs is rather difficult in contrast to the small molecule-based CSPs, several attempts have made for comprehension of the chromatographic behavior on the polysaccharide-based CSPs. In this chapter, after describing the development of the polysaccharide-based CSPs with high recognition ability, special emphasis is placed on the mechanistic study of the polysaccharide-based CSPs on the basis of spectroscopic and computational methods. © 2010 Springer-Verlag Berlin Heidelberg.

DOI： 10.1007/978-3-642-12445-7_2

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Reviews  

The development and applications of polysaccharide derivatives for the efficient chromatographic separation of enantiomers have been investigated. Direct chiral separation using chiral stationary phases (CSPs) for high-performance liquid chromatography (HPLC) has significantly evolved and has been recognized as the most popular and reliable tool for both the analysis of enantiomer compositions. One of the advantages of this method is that the association constant between enantiomers and chiral selectors can be estimated by changing the concentration of chiral selectors in mobile phases. Cellulose phenylcarbamate derivatives are also useful chiral selectors for HPLC when coated on silica gel. Monolithic silica gel supports have attracted significant attention as a supporting material for a rapid chromatographic analysis, because the pressure drop through monolithic silica gel supports is significantly lower and the column efficiency on the linear flow rate of the mobile phase is much flatter compared with the spherical silica supports.

DOI： 10.1021/cr8005558

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Separation Science  

The 4-tert-butylphenylcarbamates of cellulose and amylose bearing a small amount of 3-(triethoxysilyl)propyl residues were synthesized by a one-pot process and efficiently immobilized onto a silica gel through intermolecular polycondensation of the triethoxysilyl groups. The obtained chiral packing materials (CPMs) were evaluated by HPLC. The polysaccharide derivatives containing about 1-2% of the 3-(triethoxysilyl) propyl residue were efficiently immobilized with a high chiral recognition ability. The immobilized CPMs could be used with the eluents containing chloroform and tetrahydrofuran (THF), which cannot be used with the conventional coated-type CPMs. By using these eluents, the chiral recognition for many racemates was improved. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.

DOI： 10.1002/jssc.200900206

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記述言語：英語  

DOI： 10.1039/b808881k

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jchromb.2008.04.047

CiNii Research

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Chromatography B Analytical Technologies in the Biomedical and Life Sciences  

The polysaccharide-based chiral packing materials (CPMs) for high-performance liquid chromatography (HPLC) have been recognized as the most powerful ones for the analyzing and preparative separating of the chiral compounds. These CPMs have been conventionally prepared by coating polysaccharide derivatives on a silica gel support. This means that the solvents, which swell or dissolve the derivatives on the silica gel and reduce the performance of the chiral columns, do not allow to be applied as components of the eluents. Therefore, the polysaccharide-based CPMs can be used with a rather limited number of eluents. In order to enhance the versatility of the eluent selection for more practical and economical chromatographic enantioseparations, the polysaccharide derivatives must be immobilized onto the silica gel. This review summarizes our latest studies on the development of the immobilized-type CPMs via the radical copolymerization and the polycondensation of the polysaccharide derivatives bearing small amounts of vinyl groups and alkoxysilyl groups, respectively. © 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jchromb.2008.04.047

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-V C H VERLAG GMBH  

The enantiorecognition mechanism of several cyclodextrin derivatives is still not completely rationalized, and the application of acyclic selectors may aid to explain the role of the cavity (typical of the underivatized cyclic selectors) combined with the functional groups introduced by multistep synthesis, Octakis[(3-0,-4 '' O)-butanoyl-(1'-O,2,6-di-O)-n-pentyl]maltooctaose was applied as a chiral stationary phase for gas chromatographic enantioseparation. Selected racemic compounds were enantioseparated also on the acyclic phase. The promising results of this chiral selector [and its direct comparison with the cyclic counterpart octakis(2,6-di-O-n-pentyl-3-O-butanoyl)-y-cyclodextrin (Lipodex E)] suggest the application of other well-known spectroscopic techniques (CD, NMR) to point out further details on the mechanism of enantiorecognition. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008).

DOI： 10.1002/ejoc.200800508

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/asia.200800022

担当区分：筆頭著者   記述言語：英語  

DOI： 10.1016/j.jchromb.2008.04.047

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry an Asian Journal  

The hybrid bead-type chiral packing material (CPM) for preparative enantioseparation has been prepared from the cellulose 3,5- dimethylphenylcarbamate containing a small number of 3-(triethoxysilyl)propyl groups in the presence of tetraethyl orthosilicate, by a sol-gel reaction in an aqueous surfactant solution. The obtained hybrid bead-type CPM was packed into a column and evaluated by high-performance liquid chromatography. When compared with the commercially available Chiralpak IB, which is prepared by the immobilization of cellulose 3,5-dimethylphenylcarbamate on silica gel, the hybrid bead-type CPM was shown to exhibit a similar chiral recognition and possess a higher loading capacity. © 2008 Wiley-VCH Verlag GmbH & Co. KGaA.

DOI： 10.1002/asia.200800022

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担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Society Reviews  

Resolution of racemic compounds is one of the potential ways of obtaining both enantiomers. Among several resolution techniques in the past few decades, direct enantioseparation by high-performance liquid chromatography (HPLC) has significantly advanced, and a large number of chiral stationary phases (CSPs) for HPLC have been developed using both chiral small molecules and polymers with chiral recognition abilities. In this tutorial review, after describing the brief history and general view of CSPs, special emphasis will be placed on the studies involving the development and application of polysaccharide-based CSPs in our group. © 2008 The Royal Society of Chemistry.

DOI： 10.1039/b808881k

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Chromatography A  

The 3,5-dimethylphenylcarbamates of cellulose and amylose bearing a small amount of 3-(triethoxysilyl)propyl residues were synthesized by a simple process and efficiently immobilized onto a silica gel support by intermolecular polycondensation of the triethoxysilyl groups. The obtained chiral packing materials (CPMs) were evaluated by high-performance liquid chromatography. The polysaccharide derivatives containing about 1-2% of the 3-(triethoxysilyl)propyl residue were efficiently immobilized with a high chiral recognition. The immobilized CPMs could be used with the eluents containing chloroform and tetrahydrofuran, which cannot be used with the conventional coated-type CPMs. By using these eluents, the chiral recognitions for many racemates could be improved. © 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2007.04.054

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Separation Science  

The spherical beads consisting of cellulose 3,5-dimethylphenylcarbamate with partial hydroxyl groups were prepared to be used as chiral packing materials (CPMs) for HPLC. The beads were obtained without using macroporous silica gel, which is usually used as the support of the CPMs based on the polysaccharide derivatives. After the crosslinking in the bead with diisocyanates, such as 4,4′-diphenylmethane diisocyanate (MDI), 4,4′-dibenzyl diisocyanate (DBDI), tolylene-2,4-diisocyanate (TDI), and m-xylylene diisocyanate (XDI), the obtained beads were packed into an HPLC column. As the content of the hydroxyl groups of the cellulose derivatives decreased, the obtained CPM exhibited a higher chiral recognition ability. The beads possessed a higher loading capacity than the CPM prepared by coating the cellulose derivative on silica gel. The crosslinked beads could be used with the eluent containing chloroform. The amylose derivative beads were also prepared as a CPM for chiral HPLC. © 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/jssc.200600438

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/jssc.200600438

記述言語：英語   掲載種別：研究論文（学術雑誌）  

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

担当区分：筆頭著者   記述言語：英語  

DOI： 10.1002/tcr.20107

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Record  

Polysaccharide-based chiral packing materials (CPMs) for high-performance liquid chromatography have frequently been used not only to determine the enantiomeric excess of chiral compounds but also to preparadvely resolve a wide range of racemates. However, these CPMs can be used with only a limited number of solvents as mobile phases because some organic solvents, such as tetrahydrofuran, chloroform, and so on, dissolve or swell the polysaccharide derivatives coated on a support, e.g., silica gel, and destroy their packed columns. The limitation of mobile phase selection is sometimes a serious problem for the efficient analytical and preparative resolution of enantiomers. This defect can be resolved by the immobilization of the polysaccharide derivatives onto silica gel. Efficient immobilizations have been attained through the radical copolymerization of the polysaccharide derivatives bearing small amounts of polymerizable residues and also through the polycondensation of the polysaccharide derivatives containing a few percent of 3-(triethoxysilyl)propyl residue. © 2007 The Japan Chemical Journal Forum and Wiley Periodicals, Inc.

DOI： 10.1002/tcr.20107

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry A European Journal  

The exclusive formation of hydrogen-bonded dimers between tetraaryl and tetratosylurea calix[4]arenes has been used to prepare a series of ten "bisloop" tetraurea calix[4]arenes 3, in which adjacent phenylurea groups are covalently linked through α,ω-dioxyalkane chains. This dimerization with tetratosylurea 2 as template preorganizes the alkenyl residues of tetra(m-alkenyloxyphenyl) ureas 1 and enables their selective connection in high yield (up to 95%) by olefin metathesis followed by hydrogenation. The "bisloop" calixarenes 3 also exclusively form heterodimers with 1. Thus, in a separated metathesis/hydrogenation sequence, a series of 14 cyclic bis[2]catenanes 4, in which two calix[4]arenes are connected through their wide rims by two pairs of interlocked rings (total size 29 to 41 atoms), were prepared in yields of up to 97%. Optical resolution of these chiral bis[2]catenanes was studied by HPLC on chiral stationary phases. The single-crystal X-ray structure of one example (4(P,10)) confirmed the interlocking rings and revealed that the hydrogen-bonded dimeric capsule of the calix[4] arene can be "completely" opened. © 2007 Wiley-VCH Verlag GmbH & Co. KGaA.

DOI： 10.1002/chem.200601814

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1246/cl.2006.1250

CiNii Research

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry Letters  

Cellulose 3,5-dimethylphenylcarbamate bearing a small amount of 3-(triethoxysilyl)propyl residues was synthesized and effectively immobilized onto silica gel support for high-performance liquid chromatography by the polycondensation of triethoxysilyl groups. The immobilized chiral packing material (CPM) showed high chiral recognition as well as the conventional CPM prepared by coating the derivative onto silica gel, and can be used with a variety of eluents. Copyright © 2006 The Chemical Society of Japan.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer Preprints Japan  

Polysaccharide-based chiral stationary phases (CSPs) are known to show a broad applicability to a wide range of racemates when used as CSPs for HPLC. This type of chiral packing materials (CPMs) have usually been prepared by coating the polysaccharide derivatives onto macroporous silica gel as a support (Fig. la).¹⁾ However, the amount of the derivatives, which can be coated on silica gel, is limited; therefore, the coated-type CPMs may not be most suitable for preparative separation. In the previous study, to improve this defect, cellulose 3,5-dimethylphenylcarbamate beads were prepared by suspending cellulose derivative (3) and crosslinked with a diisocyanate.^{2, 3)} The obtained beads showed a high chiral recognition ability comparable to that of the conventional coated-type CPM and possessed a higher loading capacity, which is particularly important for preparative separations. In addition, the crosslinked beads could be used with the eluent containing chloroform. In this work, we prepared the cross-linked beads from cellulose derivatives (1-3) having ethoxysilyl group, vinyl group, and hydroxy group, respectively, and evaluated their chiral recognition ability and durability against solvents.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Separation Science  

Monolithic capillary columns containing native silica gel were covalently modified with 3,5-disubstituted phenylcarbamate derivatives of cellulose and amylose and applied for enantioseparations in capillary LC. The method previously used for covalent immobilization of polysaccharide phenylcarbamate derivatives onto the surface of microparticulate silica gel was successfully adapted for in situ modification of monolithic fused-silica capillary columns. The effects of the nature of polysaccharide and the substituents, as well as of multiple covalent immobilization of polysaccharide derivative on chromatographic performance of capillary columns were studied. The capillary columns obtained using this technique are stable in all solvents commonly used in LC and exhibit promising enantiomer resolving ability. © 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/jssc.200500388

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/jssc.200500388

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1246/cl.2006.1250

担当区分：筆頭著者   記述言語：英語  

DOI： 10.1295/polymj.38.91

記述言語：日本語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Polymer Preprints Japan  

The 3,5-dimethyl- and 3,5-dichlorophenylcarbamates of cellulose and the 3,5-dimethylphenylcarbamate of amylose bearing a small amount of 3-(triethoxysilyl)propyl residues (1-3 in Fig. 1) were synthesized and effectively immobilized onto silica support for high-performance liquid chromatography (HPLC) by a simple process. The immobilization was efficiently attained through polycondensation of triethoxysilyl groups. The immobilized chiral packing materials (CPMs) showed high chiral recognition as well as the conventional CPMs prepared by coating the derivatives onto silica gel, and can be used with a variety of eluents.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer Journal  

Polysaccharide derivatives, such as phenylcarbamates and benzoates of cellulose and amylose, are known to show high chiral recognition abilities for many racemates when used as chiral stationary phases (CSPs) for high-performance liquid chromatography (HPLC). This type of CSPs has usually been prepared by coating the polysaccharide derivatives onto a macroporous silica gel without a chemical bond. Therefore, rather limited numbers of solvents can be used as eluents, and solvents, such as chloroform and tetrahydrofuran (THF), which swell or dissolve the polysaccharide derivatives cannot be used. The selection of a suitable eluent is very important for both analytical and preparative separations. In order to enhance the versatility of the polysaccharide derivative-based CSPs, the derivatives have to be immobilized. Here we review the immobilization methods of the polysaccharide derivatives mainly onto silica gel.

DOI： 10.1295/polymj.38.91

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chirality  

Phenylcarbonate, benzoylformate, and p-toluenesulfonylcarbamate of cellulose and five new benzoylcarbamate derivatives of both cellulose and amylose were synthesized and their chiral recognition abilities were evaluated as chiral stationary phases (CSPs) for high-performance liquid chromatography (HPLC). Cellulose benzoylcarbamate has a higher chiral recognition ability compared to phenylcarbonate, p-toluenesulfonylcarbamate, and benzoylformate of cellulose. The benzoylcarbamate derivatives exhibited a characteristic chiral recognition for the racemates, which bear a hydrogen atom capable of hydrogen bonding to the carbonyl group of the benzoylcarbamates. The structures of the benzoylcarbamates were investigated by CD spectroscopy. © 2005 Wiley-Liss, Inc.

DOI： 10.1002/chir.20168

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/chir.20168

記述言語：日本語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Polymer Preprints Japan  

Polysaccharide-based chiral stationary phases (CSPs) are known to show a high chiral recognition for a wide range of racemates when used as CSPs for HPEC. This type chiral packing materials (CPMs) have been prepared by coating polysaccharide derivatives by ca. 20 wt% on macroporous silica gel as a support (Fig. 1a).¹⁾ However, the amount of the derivatives, which can be coated on silica gel, is limited; therefore, the coated-type CPMs may not be most suitable for preparative separation. In the previous study, to overcome this defect, cellulose 3,5-dimethylphenylcarbamate beads were prepared by suspending cellulose derivative (1) and crosslinked with the diisocyanate (3).^{2 3)} The obtained beads showed a high chiral recognition ability comparable to that of the conventional coatedtype CPM and possessed a higher loading capacity, which is particularly important for preparative separations. The crosslinked beads can be used with the eluent containing chlorform. In this work, we prepared the cross-linked beads from cellulose derivative (2) having hydroxyl groups non-regioselectively and various diisocyanates (3-6), and evaluated their chiral recognition ability and durability against solvents.

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記述言語：日本語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Polymer Preprints Japan  

Polysaccharide-based chiral stationary phases (CSPs) are known to show a high chiral recognition for a wide range of racemates when used as CSPs for HPLC. This type chiral packing materials have been prepared by coating polysaccharide derivatives by ca. 20 wt% on macroporous silica gel as a support. However, the amount of the derivatives, which can be coated on silica gel, is limited. In the present study, in order to avoid the use of the macroporous silica support and to enhance the loading capacity of racemates, cellulose and amylose 3,5-dimethylphenylcarbamate beads were prepared by suspending the polysaccharide derivatives dissolved in THF - 1-heptanol mixture in water containing sodium lauryl sulphate. After crosslinking in a bead with diisocyanate, the obtained beads were packed into an HPLC column. The beads showed a high chiral recognition ability as well as conventional CSPs and a higher loading capacity. The crosslinked beads can be used with the eluent containing chloroform. In this presentation, the authors would like to show the details of the chiral recognition ability and the durability against solvents affected by the kind of the crosslinkers.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry Letters  

Crosslinked beads, which can be used as a chiral packing material (CPM) for high-performance liquid chromatography (HPLC), were prepared using a cellulose phenylcarbamate derivative. The spherical beads were first prepared with partially derivatized cellulose 3,5-dimethylphenylcarbamate, which was then crosslinked with a diisocyanate. The obtained beads had a higher loading capacity than the corresponding conventional CPM prepared by coating the derivative on silica gel, and were not damaged when used with an eluent containing chloroform which cannot be used with the coated CPM.

DOI： 10.1246/cl.2004.1188

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Chromatography A  

Covalent immobilization of 3,5-dimethylphenylcarbamate derivative of cellulose was performed in situ onto native silica monoliths cladded in a 50 mm × 4.6 mm polyether ether ketone high-performance liquid chromatographic (HPLC) column. The covalent attachment of cellulose derivative in the range of 16-19% (w/w) was performed via an epoxide moiety. The column obtained by this technique combines the high enantiomer-resolving ability of the polysaccharide derivative with favourable dynamic properties of monolithic HPLC columns. The covalent attachment of the cellulose derivative enables this column to be used in combination with the mobile phases which are incompatible with coated-type polysaccharide columns due to solubility of chiral selector in some organic solvents. © 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2004.05.011

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry A European Journal  

Bis-loop tetraurea calix[4]arene 6 has been prepared by acylation of the wide-rim calix[4]arene tetraamine 1 with the activated bis(urethane) 8 under dilution conditions. Similarly the bis(Boc-protected) tetraamine 2 is converted into the mono-loop derivative 3 which after deprotection and acylation gives the bisalkenyl derivative 5. In apolar solvents this tetraurea calix[4]arene 5 forms regioselectively a single hydrogen-bonded homodimer, from which the bis[2]catenane 10a is formed in 49% by a metathesis reaction followed by hydrogenation. Bisloop derivative 6 forms no homodimers for steric reasons, but a stoichiometric mixture with the open-chain tetraalkenyl derivative 7a contains exclusively the heterodimer. Metathesis and subsequent hydrogenation now yields 65% of the pure bis[2]catenane 10a which could not be isolated from the complex reaction mixture obtained from the homodimer 7a·7a. The chirality of 10a (D<inf>2</inf> symmetry) has been verified by optical resolution using HPLC on a chiral stationary phase.

DOI： 10.1002/chem.200400195

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/chem.200400195

記述言語：英語   掲載種別：研究論文（学術雑誌）  

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1246/cl.2004.1188

DOI： 10.1021/acs.macromol.8b00229

研究データ保存先URL： http://orcid.org/0000-0002-5211-2421

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DOI： 10.1021/jacs.7b10981

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DOI： 10.1021/acsmacrolett.8b00106

研究データ保存先URL： http://orcid.org/0000-0002-5211-2421

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DOI： 10.1016/j.polymer.2017.04.032

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記述言語：日本語   掲載種別：書評論文，書評，文献紹介等  

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記述言語：日本語   掲載種別：書評論文，書評，文献紹介等  

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記述言語：日本語   掲載種別：書評論文，書評，文献紹介等  

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DOI： 10.1002/chir.20168

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記述言語：日本語   掲載種別：書評論文，書評，文献紹介等  

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記述言語：日本語   掲載種別：書評論文，書評，文献紹介等  

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DOI： 10.1002/chem.200400195

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