研究者詳細 - 井改　知幸

論文 - 井改　知幸

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Optically-pure triptycene-based metallomacrocycles and homochiral self-sorting assisted by ladder formation 招待有り査読有り国際共著

Oki, Kosuke Zheng, Wei Yashima, Eiji Ikai, Tomoyuki

Chem. Commun. 59 巻頁： 8989 - 8992 2023年6月

Amplification of macromolecular helicity of poly(biphenylylacetylene)s composed of a small amount of chiral [5]helicene units 査読有り

Ikai Tomoyuki, Anzai Shun, Oki Kosuke, Yashima Eiji

JOURNAL OF POLYMER SCIENCE 2022年12月

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

Web of Science

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Chiral and Achiral Pendant-Bound Poly(biphenylylacetylene)s Bearing Amide and/or Carbamate Groups: One-Handed Helix Formations and Chiral Recognition Abilities 査読有り

Ikai Tomoyuki, Okuda Shogo, Aizawa Motoki, Yashima Eiji

MACROMOLECULES 55 巻 ( 16 ) 頁： 7023 - 7031 2022年8月

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

Web of Science

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Catalytic One-Handed Helix Induction and Subsequent Static Memory of Poly(biphenylylacetylene)s Assisted by a Small Amount of Carboxy Groups Introduced at the Pendants 査読有り

Tomoyuki Ikai, Shoki Takeda, Eiji Yashima

ACS Macro Letters 2022年3月

Macromolecular helicity induction and static helicity memory of poly(biphenylylacetylene)s bearing aromatic pendant groups and their use as chiral stationary phases for high-performance liquid chromatography 招待有り査読有り

Ikai Tomoyuki, Okuda Shogo, Yashima Eiji

CHIRALITY 34 巻 ( 2 ) 頁： 306 - 316 2022年2月

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

Web of Science

Scopus

PubMed

Chiral amplification of supramolecular coassemblies of chiral and achiral acylhydrazine-functionalized biphenyls and their copolymers 査読有り

Ikai Tomoyuki, Kawabata Satoshi, Okuda Shogo, Ousaka Naoki, Yashima Eiji

POLYMER JOURNAL 2021年8月

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：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

Web of Science

Scopus

Water-Mediated Reversible Control of Three-State Double-Stranded Titanium(IV) Helicates 査読有り

Naoki Ousaka, Manabu Itakura, Akira Nagasaka, Masaki Ito, Tomonari Hattori, Daisuke Taura, Tomoyuki Ikai, Eiji Yashima

Journal of the American Chemical Society 2021年3月

One-Step Simultaneous Synthesis of Circularly Polarized Luminescent Multiple Helicenes Using a Chrysene Framework 査読有り

Ikai Tomoyuki, Yamakawa Shoya, Suzuki Nozomu, Yashima Eiji

CHEMISTRY-AN ASIAN JOURNAL 2021年2月

Cellulose phenylcarbamate-derived hybrid bead-type chiral packing materials for efficient chiral recognition 査読有り

Li Geng, Dai Xiao, Min Yixuan, Yu Chang, Ikai Tomoyuki, Zhang Lili, Shen Jun, Okamoto Yoshio

CELLULOSE 28 巻 ( 1 ) 頁： 347 - 358 2021年1月

Helix-Sense-Selective Encapsulation of Helical Poly(lactic acid)s within a Helical Cavity of Syndiotactic Poly(methyl methacrylate) with Helicity Memory 査読有り

Ikai Tomoyuki, Kawabata Satoshi, Mamiya Fumihiko, Taura Daisuke, Ousaka Naoki, Yashima Eiji

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 142 巻 ( 52 ) 頁： 21913 - 21925 2020年12月

Peripherally Donor-Installed 7,8-Diaza[5]helicenes as a Platform for Helical Luminophores 査読有り

Ikari Yuta, Kaihara Takahito, Goto Shimpei, Bovenkerk Marcel, Grenz David C., Esser Birgit, Ferreira Marli, Stachelek Patrycja, Data Przemyslaw, Yoshida Takumu, Ikai Tomoyuki, Tohnai Norimitsu, Minakata Satoshi, Takeda Youhei

SYNTHESIS-STUTTGART 2020年12月

Catalytic one-handed helix-induction and memory of amphiphilic poly(biphenylylacetylene)s in water 招待有り査読有り

Ikai, Tomoyuki Mizumoto, Kosuke Ishidate, Ryoma Kitzmann, Winald R. Ikeda, Riho Yokota, Chiaki Maeda, Katsuhiro Yashima, Eiji

Giant 2020年6月

Chiral Guest-Induced Catalytic Deracemization of a Spiroborate-Based Double-Stranded Helicate Bearing a Bisporphyrin Unit with Acids 査読有り

Ito, Masaki Ikai, Tomoyuki Yamamoto, Shinya Taura, Daisuke Ousaka, Naoki Yashima, Eiji

Chem. Lett. 2020年6月

Helical Assemblies of One-Dimensional Supramolecular Polymers Composed of Helical Macromolecules: Generation of Circularly Polarized Light Using an Infinitesimal Chiral Source

Ikai Tomoyuki, Okubo Mitsuhiro, Wada Yuya

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 142 巻 ( 6 ) 頁： 3254-3261 2020年2月

Chiral/Achiral Copolymers of Biphenylylacetylenes Bearing Various Substituents: Chiral Amplification through Copolymerization, Followed by Enhancement/Inversion and Memory of the Macromolecular Helicity

Ikai Tomoyuki, Ishidate Ryoma, Inoue Kazuya, Kaygisiz Kubra, Maeda Katsuhiro, Yashima Eiji

MACROMOLECULES 53 巻 ( 3 ) 頁： 973-981 2020年2月

Dithiocarbamate-modified cellulose resins: A novel adsorbent for selective removal of arsenite from aqueous media.

Nakakubo K, Hasegawa H, Ito M, Yamazaki K, Miyaguchi M, Biswas FB, Ikai T, Maeda K

Journal of hazardous materials 380 巻頁： 120816 2019年12月

Helicity induction and memory effect in poly(biphenylylacetylene)s bearing various functional groups and their use as switchable chiral stationary phases for HPLC

Ishidate Ryoma, Sato Toru, Ikai Tomoyuki, Kanoh Shigeyoshi, Yashima Eiji, Maeda Katsuhiro

POLYMER CHEMISTRY 10 巻 ( 46 ) 頁： 6260-6268 2019年12月

Synthesis of helical pi-conjugated polymers bearing pyridine N-oxide pendants and asymmetric allylation of aldehydes in the helical cavity

Ikai Tomoyuki, Yoshida Takumu

ORGANIC & BIOMOLECULAR CHEMISTRY 17 巻 ( 37 ) 頁： 8537-8540 2019年10月

Helicity Induction and Its Static Memory of Poly(biphenylylacetylene)s Bearing Pyridine N-Oxide Groups and Their Use as Asymmetric Organocatalysts

Ando Mitsuka, Ishidate Ryoma, Ikai Tomoyuki, Maeda Katsuhiro, Yashima Eiji

JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY 2019年9月

Optically active triptycenes containing hexa-peri-hexabenzocoronene units

Wada Yuya, Shinohara Ken-ichi, Ikai Tomoyuki

CHEMICAL COMMUNICATIONS 55 巻 ( 76 ) 頁： 11386-11389 2019年9月

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