研究者詳細 - 忍久保　洋

論文 - 忍久保　洋

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Stacked antiaromatic porphyrins 査読有り国際誌

Nozawa Ryo, Tanaka Hiroko, Cha Won-Young, Hong Yongseok, Hisaki Ichiro, Shimizu Soji, Shin Ji-Young, Kowalczyk Tim, Irle Stephan, Kim Dongho, Shinokubo Hiroshi

NATURE COMMUNICATIONS 7 巻頁： 13620 2016年11月

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：Nature Communications

Aromaticity is a key concept in organic chemistry. Even though this concept has already been theoretically extrapolated to three dimensions, it usually still remains restricted to planar molecules in organic chemistry textbooks. Stacking of antiaromatic π-systems has been proposed to induce three-dimensional aromaticity as a result of strong frontier orbital interactions. However, experimental evidence to support this prediction still remains elusive so far. Here we report that close stacking of antiaromatic porphyrins diminishes their inherent antiaromaticity in the solid state as well as in solution. The antiaromatic stacking furthermore allows a delocalization of the π-electrons, which enhances the two-photon absorption cross-section values of the antiaromatic porphyrins. This feature enables the dynamic switching of the non-linear optical properties by controlling the arrangement of antiaromatic π-systems on the basis of intermolecular orbital interactions.

DOI： 10.1038/ncomms13620

Reversible Carbon-Carbon Bond Breaking and Spin Equilibria in Bis(pyrimidinenorcorrole) 査読有り国際誌

Liu Bin, Yoshida Takuya, Li Xiaofang, Stepien Marcin, Shinokubo Hiroshi, Chmielewski Piotr J.

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION 55 巻 ( 42 ) 頁： 13142 - 13146 2016年10月

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 homolytic dissociation of the bis(pyrimidinenorcorrole) σ-dimer was elucidated by means of variable temperature ESR and1H NMR spectroscopy, mass spectrometry, and optical spectrocopy. Dehydrogenation of the σ-dimer yielded another dimer displaying a singlet–triplet equilibrium in solution, strong NIR absorption (1570 nm), and a narrow electrochemical HOMO–LUMO gap (0.74 V).

DOI： 10.1002/anie.201607237

Syntheses and Properties of Antiaromatic Porphyrinoids 査読有り国際誌

Satoru Hiroto, Hiroshi Shinokubo

Handbook of Porphyrin Science (Volumes 36 – 40) 2016年7月

beta-to-beta 2,5-Pyrrolylene-Linked Cyclic Porphyrin Oligomers 査読有り国際誌

Rao Yutao, Kim Jun Oh, Kim Woojae, Zhong Guangming, Yin Bangshao, Zhou Mingbo, Shinokubo Hiroshi, Aratani Naoki, Tanaka Takayuki, Liu Shubin, Osuka Atsuhiro, Kim Dongho, Song Jianxin

CHEMISTRY-A EUROPEAN JOURNAL 22 巻 ( 26 ) 頁： 8801 - 8804 2016年6月

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：Wiley

β-to-β 2,5-Pyrrolylene linked cyclic porphyrin oligomers have been synthesized by Suzuki–Miyaura coupling of 2,5-diborylpyrrole and 3,7-dibromoporphyrin. The cyclic porphyrin oligomers exhibit roughly coplanar structures, strong excitonic coupling, small electrochemical HOMO–LUMO gaps, and ultrafast excitation energy transfer between the neighboring porphyrins via the pyrrolylene bridge.

DOI： 10.1002/chem.201601306

Synthesis of Free-Base 10-Azacorroles 査読有り国際誌

Omori Hiroto, Hiroto Satoru, Shinokubo Hiroshi

ORGANIC LETTERS 18 巻 ( 12 ) 頁： 2978 - 2981 2016年6月

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：ACS Publications

A novel synthetic protocol has been developed for free-base 10-azacorroles. Ni(0)-mediated homocoupling of nitrogen-bridged bisdipyrrin Zn(II) complexes afforded a series of free-base 5,15-diaryl-10-azacorroles in good yields. Pd(II) and Cu(II) complexes have been prepared through metalation of free-base 10-azacorroles. Optical and electrochemical properties of 10-azacorrole metal complexes can be tuned by meso-aryl substituents and central metals. Cyclic voltammetry and theoretical calculations elucidated that the central metals of 10-azacorroles significantly affected their electronic properties.

DOI： 10.1021/acs.orglett.6b01323

Fully-substituted 1,3-Butadienes as pi-Conjugated Linkers between Pyrenes 査読有り国際誌

Oda Kazuma, Hiroto Satoru, Sakamaki Daisuke, Seki Shu, Shinokubo Hiroshi

CHEMISTRY LETTERS 45 巻 ( 4 ) 頁： 403 - 405 2016年4月

担当区分：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：公益社団法人日本化学会

Pyrenyl-substituted 1,3-butadienes bearing alkyl and aryl groups have been synthesized by palladium-catalyzed addition of 2-borylpyrene to internal alkynes. On UV irradiation, 1-pyrenylbutadienes undergo photochromism in solution. In the solid state, 1-pyrenyl-1,2,3,4-tetraaryl-1,3-butadiene exhibits red-shifted and broad emission as compared with the alkylated butadiene. The charge-carrier mobility of 1-pyrenyl-1,2,3,4-tetraalkyl-1,3-butadiene is higher than that of the arylated butadiene.

DOI： 10.1246/cl.151181

Control of Conformation and Chirality of Nonplanar pi-Conjugated Diporphyrins Using Substituents and Axial Ligands 査読有り国際誌

Ito Satoru, Hiroto Satoru, Ousaka Naoki, Yashima Eiji, Shinokubo Hiroshi

CHEMISTRY-AN ASIAN JOURNAL 11 巻 ( 6 ) 頁： 936 - 942 2016年3月

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：Chemistry - An Asian Journal

Nonplanar conformations of pyrazine-fused ZnII diporphyrins could be controlled by the choice of the meso-aryl substituents and an axial ligand on the central metals. ZnII diporphyrins bearing sterically demanding meso-aryl groups with ortho-substituents led to a twisted chiral D2 conformation, while an achiral C2h form was preferred in the case of aryl groups without ortho-substituents. Helical chirality induction on ZnII diporphyrins in the twisted conformation was achieved by controlling their handedness of the molecular twist through coordination of optically active 1-phenethylamine. But there′s a twist! Conformations of nonplanar ZnII diporphyrins could be controlled by the meso-aryl substituents and an axial ligand on the central metals. Helical chirality induction on ZnII diporphyrins was achieved by controlling their handedness of the molecular twist through coordination of an optically active amine.

DOI： 10.1002/asia.201600105

Chemo- and Regioselective Reduction of 5,15-Diazaporphyrins Providing Antiaromatic Azaporphyrinoids 査読有り国際誌

Yamaji Ayaka, Tsurugi Hayato, Miyake Yoshihiro, Mashima Kazushi, Shinokubo Hiroshi

CHEMISTRY-A EUROPEAN JOURNAL 22 巻 ( 12 ) 頁： 3956 - 3961 2016年3月

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：Chemistry - A European Journal

Reagent-controlled chemo- and regioselective reduction of 5,15-diazaporphyrins has been developed. The selective reduction of carbon-carbon double bonds of diazaporphyrins provides 18 π aromatic isobacteriochlorin-type products, whereas the reduction of carbon-nitrogen double bonds leads to selective formation of 20 π N,N′-dihydrodiazaporphyrins in excellent yields. The distinct antiaromatic character of N,N′-dihydrodiazaporphyrins has been revealed. The free-base N,N′-dihydrodiazaporphyrin exhibits slower inner NH tautomerism than that in the corresponding 18 π porphyrins. Reagent-controlled chemo- and regioselective reduction of 5,15-diazaporphyrins has been developed. The selective reduction of carbon-carbon double bonds of diazaporphyrins provides aromatic isobacteriochlorin-type products, whereas the reduction of carbon-nitrogen double bonds leads to N,N′-dihydrodiazaporphyrins with distinct antiaromatic character.

DOI： 10.1002/chem.201600066

脱炭酸的アリール化によるグラフェン量子ドットの可溶化と発光色の制御査読有り国際誌

小田一磨, 廣戸聡, 忍久保洋

応用物理学会学術講演会講演予稿集 2016.1 巻 ( 0 ) 頁： 3881 - 3881 2016年3月

The synthesis of Ni-II and Al-III 10-azacorroles through coordination-induced cyclisation involving 1,2-migration 査読有り国際誌

Omori Hiroto, Hiroto Satoru, Shinokubo Hiroshi

CHEMICAL COMMUNICATIONS 52 巻 ( 17 ) 頁： 3540 - 3543 2016年

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

We have synthesized NiII and AlIII 10-azacorroles through coordination-induced cyclisation of nitrogen-bridged bisdipyrrins. AlIII 10-azacorrole displayed contrasting optoelectronic behaviours from NiII 10-azacorrole, underlining the different electronic effects of the azacorrole ligand from the porphyrin.

DOI： 10.1039/c5cc10247b

Ni-II tetrahydronorcorroles: antiaromatic porphyrinoids with saturated pyrrole units 査読有り国際誌

Nozawa Ryo, Yamamoto Keitaro, Hisaki Ichiro, Shin Ji-Young, Shinokubo Hiroshi

CHEMICAL COMMUNICATIONS 52 巻 ( 44 ) 頁： 7106 - 7109 2016年

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

While hydrogenated porphyrins are abundant in natural and synthetic compounds, antiaromatic hydrogenated porphyrinoids have not been synthesized to date. Here, we report bacteriochlorin-like NiII tetrahydronorcorrole complexes as the first examples of antiaromatic porphyrinoids that contain saturated pyrrole units.

DOI： 10.1039/c6cc02918c

Indolylindolinone: Easily Accessible, Tunable, and Wide-range Absorbing Dyes 査読有り国際誌

Shigeno Ami, Matsuno Takashi, Hiroto Satoru, Shinokubo Hiroshi

CHEMISTRY LETTERS 44 巻 ( 12 ) 頁： 1703 - 1705 2015年12月

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：公益社団法人日本化学会

Dehydrative coupling between indoles and isatins provided indolylindolinones in good yields as novel dyes with wide-range absorption due to intramolecular charge-transfer interactions. The HOMO and LUMO levels of indolylindolinones could be manipulated individually by the introduction of substituents on the indole and isatin units, respectively. Indolylindolinones served as a bidentate ligand to Ni(II) and Cu(II) ions to provide stable metal complexes. Metal coordination induced large bathochromic shift of the lowest-energy absorption band to the near-infrared region.

DOI： 10.1246/cl.150815

Twisting of π-conjugated plane to one rotation 査読有り国際誌

Hiroto S., Shinokubo H.

Kobunshi 64 巻 ( 11 ) 頁： 713 - 714 2015年11月

担当区分：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：Kobunshi

We have established the facile and efficient protocol to synthesize distorted 71-conjugated molecules. Oxidation of amino-substituted porphyrins proceeded with high regioselectivity to produce pyrazine fused dimers. X-ray diffraction analysis revealed its highly twisted structure. Electrochemical and optical measurements indicated the twisting mostly influences on HOMO. The sequential use of our protocol has achieved the synthesis of unidirectionally twisted porphyrin tetramers efficiently. NMR analysis suggested that the racemization barrier of twisting increases on oligomerization. To the best of our knowledge, this is the first observation of a similar phenomenon observed in polymer science for twisted, jt-conjugated molecules. The present findings represent an important advance towards the long-term goal of preparing -conjugated molecular wires, whose properties can be fine-tuned through molecular twisting.

A Stable Organic -Radical of a Zinc(II)-Copper(I)-Zinc(II) Complex of Decaphyrin 査読有り国際誌

Tanaka Yasuo, Yoneda Tomoki, Furukawa Ko, Koide Taro, Mori Hirotaka, Tanaka Takayuki, Shinokubo Hiroshi, Osuka Atsuhiro

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION 54 巻 ( 37 ) 頁： 10908 - 10911 2015年9月

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：Angewandte Chemie - International Edition

A Zn<sup>II</sup>-Cu<sup>I</sup>-Zn<sup>II</sup> heterotrimetal complex of decaphyrin was synthesized by stepwise metalations: metalation of a [46]decaphyrin with Zn<sup>II</sup> ions to produce a 46π decaphyrin bis(Zn<sup>II</sup>) complex and its subsequent metalation with Cu<sup>II</sup> ion. In the second metalation step, it has been shown that Cu<sup>II</sup> ion is reduced to a Cu<sup>I</sup> ion in the complex and a dianionic bis(Zn<sup>II</sup>) containing [46]decaphyrin ligand is oxidized to the corresponding monoanionic [45]decaphyrin ligand, indicating a non-innocent nature of the decaphyrin ligand. Despite the radical nature, the heterotrimetal complex is fairly stable under ambient conditions and exhibits almost no intermolecular magnetic interaction, owing to extensive delocalization of an unpaired electron in the large π-conjugated circuit of decaphyrin moiety. Radical racetrack: Cu<sup>II</sup> metalation of a [46]decaphyrin bis(Zn<sup>II</sup>) complex gave a Zn<sup>II</sup>-Cu<sup>I</sup>-Zn<sup>II</sup> heterotrimetal complex of decaphyrin consisting of a central Cu<sup>I</sup> ion and a monoanionic 45π radical of decaphyrin.

DOI： 10.1002/anie.201505130

Nitrogen-embedded buckybowl and its assembly with C[60] 査読有り国際誌

Yokoi Hiroki, Hiraoka Yuya, Hiroto Satoru, Sakamaki Daisuke, Seki Shu, Shinokubo Hiroshi

Nature Communications 6 巻 2015年9月

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）

Curved π-conjugated molecules have attracted considerable interest because of the unique properties originating from their curved π surface. However, the synthesis of such distorted molecules requires harsh conditions, which hamper easy access to heteroatom-containing curved π systems. Here we report the synthesis of a π-extended azacorannulene with nitrogen in its centre. The oxidation of 9-aminophenanthrene provides tetrabenzocarbazole, which is converted to the azabuckybowl through palladium-catalysed intramolecular coupling. The electron-donating nature and curved π surface of the azabuckybowl enable its tight association with C[60] in solution and solid states. High charge mobility is observed for the azabuckybowl/C[60] assembly. This compound may be of interest in the fields of curved π systems as fullerene hosts, anisotropic π donors and precursors to nitrogen-containing nanocarbon materials.

Nitrogen-embedded buckybowl and its assembly with C-60 査読有り国際誌

Yokoi Hiroki, Hiraoka Yuya, Hiroto Satoru, Sakamaki Daisuke, Seki Shu, Shinokubo Hiroshi

NATURE COMMUNICATIONS 6 巻頁： 8215 2015年9月

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 Communications

Curved π-conjugated molecules have attracted considerable interest because of the unique properties originating from their curved π surface. However, the synthesis of such distorted molecules requires harsh conditions, which hamper easy access to heteroatom-containing curved π systems. Here we report the synthesis of a π-extended azacorannulene with nitrogen in its centre. The oxidation of 9-aminophenanthrene provides tetrabenzocarbazole, which is converted to the azabuckybowl through palladium-catalysed intramolecular coupling. The electron-donating nature and curved π surface of the azabuckybowl enable its tight association with C60 in solution and solid states. High charge mobility is observed for the azabuckybowl/C60 assembly. This compound may be of interest in the fields of curved π systems as fullerene hosts, anisotropic π donors and precursors to nitrogen-containing nanocarbon materials.

DOI： 10.1038/ncomms9215

Regioselective Nucleophilic Functionalization of Antiaromatic Nickel(II) Norcorroles 査読有り国際誌

Nozawa Ryo, Yamamoto Keitaro, Shin Ji-Young, Hiroto Satoru, Shinokubo Hiroshi

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION 54 巻 ( 29 ) 頁： 8454 - 8457 2015年7月

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

Treatment of antiaromatic nickel(II) norcorrole with potassium cyanide provided nickel(II) 3-cyanonorcorrole with perfect regioselectivity without the help of a catalyst. The reaction of the nickel(II) norcorrole with phenol or thiophenol in the presence of a base also yielded substitution products. The antiaromatic 16π conjugation system in the norcorrole core was preserved in the functionalized products. Introduction of phenylthio groups significantly decreased the HOMO-LUMO gap and enhanced the near IR absorption property.

DOI： 10.1002/anie.201502666

Synthesis of Highly Twisted and Fully pi-Conjugated Porphyrinic Oligomers 査読有り国際誌

Ito Satoru, Hiroto Satoru, Lee Sangsu, Son Minjung, Hisaki Ichiro, Yoshida Takuya, Kim Dongho, Kobayashi Nagao, Shinokubo Hiroshi

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 137 巻 ( 1 ) 頁： 142 - 145 2015年1月

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

Highly twisted π-conjugated molecules have been attractive but challenging targets. We report here an efficient synthesis of highly twisted diporphyrins with 126° and 136° twist angles that involves an oxidative fusion reaction of planar aminoporphyrin precursors at room temperature. Repeated amination-oxidative fusion sequences provide a unidirectionally twisted tetramer. The twisting angle of the tetramer is 298°.

DOI： 10.1021/ja511905f

PALLADIUM-CATALYZED [3+2] ANNULATION OF meso-BROMOPORPHYRINS WITH SILYLACETYLENES AND DESILYLATION OF 8(a)-SILYL-7,8-DEHYDROPURPURIN 査読有り国際誌

Fukui Norihito, Arai Seiji, Shinokubo Hiroshi, Yorimitsu Hideki, Osuka Atsuhiro

HETEROCYCLES 90 巻 ( 1 ) 頁： 252 - 260 2015年1月

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：Heterocycles

Palladium-catalyzed [3+2] annulation of meso-bromoporphyrins with trimethylsilyl-, tert-butyldimethylsilyl-, and triisopropylsilylacetylenes afforded 8a-silyl-7,8-dehydropurpurins. Protodesilylation of 8a-trimethylsilyl-7,8-dehydropurpurin resulted in the first synthesis of an 8a,8b-unsubstituted 7,8-dehydropurpurin.

DOI： 10.3987/COM-14-S(K)15

Synthesis of Novel Porphyrinoids from Dipyrrins 招待有り査読有り国際誌

Hiroshi Shinokubo

Chemical Science of Electron Systems 頁： 243 - 255 2015年1月

担当区分：筆頭著者,　最終著者,　責任著者記述言語：英語掲載種別：論文集(書籍)内論文出版者・発行元：Springer Japan

Most syntheses of meso-substituted porphyrinoid rely on acid-catalyzed condensation of pyrrole segments with aldehyde units followed by oxidation. This standard procedure is convenient but generally is low yielding. However, modern synthetic methodologies would offer an expeditious route to several intriguing porphyrinoids. In particular, the metal template strategy using dipyrrin metal complexes is effective to construct porphyrin-like cyclic π-conjugated systems, which are otherwise difficult to access by the conventional methodology.

DOI： 10.1007/978-4-431-55357-1_14

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