研究者詳細 - 福井　識人

論文 - 福井　識人

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Synthesis of Hydroxyisooxophlorins by Oxidative Degradation of meso-Hydroxyporphyrins 査読有り

Asahi Takiguchi, Norihito Fukui, Hiroshi Shinokubo

ORGANIC LETTERS 21 巻 ( 11 ) 頁： 3950 - 3953 2019年6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：AMER CHEMICAL SOC

Hydroxyisooxophlorin is an oxidatively degraded porphyrin that contains one carbonyl carbon, one hydroxymethylene group, and two sp(2)-methine groups at its meso positions. Here we report that oxidation of a free-base meso-hydroxyporphyrin with [bis(trifluoroacetoxy)iodo]benzene in the presence of H2O afforded two regioisomers of hydroxyisooxophlorins, 10-hydroxy-10-iso-5-oxophlorin and 15-hydroxy-15-iso-5-oxophlorin, as major and minor products, respectively. We also examined the reaction mechanism, acid-mediated isomerization, metal complexation behavior, and physical properties of these molecules.

DOI： 10.1021/acs.orglett.9b01066

Web of Science

Scopus

Organic Transformations by the Hydrosilane-Alkoxide System 査読有り

Fukui Norihito

JOURNAL OF SYNTHETIC ORGANIC CHEMISTRY JAPAN 77 巻 ( 5 ) 頁： 512 - 513 2019年5月

Macroscopically Anisotropic Structures Produced by Light-induced Solvothermal Assembly of Porphyrin Dimers 査読有り

Yamamoto Yasuyuki, Nishimura Yushi, Tokonami Shiho, Fukui Norihito, Tanaka Takayuki, Osuka Atsuhiro, Yorimitsu Hideki, Iida Takuya

SCIENTIFIC REPORTS 8 巻 2018年7月

Diarylamine-Fused Subporphyrins: Proof of Twisted Intramolecular Charge Transfer (TICT) Mechanism 査読有り

Koki Kise, Yongseok Hong, Norihito Fukui, Daiki Shimizu, Dongho Kim, Atsuhiro Osuka

Chemistry - A European Journal 24 巻 ( 33 ) 頁： 8306 - 8310 2018年6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：Wiley-VCH Verlag

Diarylamine-fused subporphyrins 1 a and 1 b were synthesized from β,β-diiodo-meso-chloro subporphyrin 2 through a one-pot procedure involving nucleophilic aromatic substitution and SRN1-type intramolecular fusion reaction as the first example of meso-nitrogen-embedded subporphyrin. While non-fused counterparts 3 b and 4 b display effective fluorescence quenching due to twisted intramolecular charge transfer (TICT) in CH2Cl2 at room temperature, 1 b emits fluorescence with ΦF=0.18 under the same conditions, because conformational twisting is not allowed due to the fused structure. In addition, the oxidative titration with tris(4-bromophenyl)ammoniumyl hexachloroantimonate gave cation radical 7 for 1 a and cation radical and dication for 1 b. Actually, cation radical 7 was isolated through separation over silica gel column but was found to slowly decompose in concentrated solutions.

DOI： 10.1002/chem.201801576

Web of Science

Scopus

Metalation Control of Open-Shell Character in meso-meso Linked Porphyrin meso-Oxy Radical Dimers 査読有り

Yuta Jun-i, Norihito Fukui, Ko Furukawa, Atsuhiro Osuka

Chemistry - A European Journal 24 巻 ( 7 ) 頁： 1528 - 1532 2018年2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：Wiley-VCH Verlag

Control of open-shell character of meso-meso linked porphyrin meso-oxy radical dimers has been demonstrated by core metalation. Namely, NiII-porphyrin dimer 6Ni exhibits a clear 1H NMR spectrum and a distorted but rather coplanar quinonoidal structure consisting of two ruffled porphyrin rings, in accordance with the previous report. Freebase dimer 6H2 shows a similar quinonoidal structure in the solid state but displays slightly broader and temperature-dependent 1H NMR spectra, indicating a partial diradical character in solution that increases at high temperature. In sharp contrast, bis-imidazole-coordinated ZnII-porphyrin dimer 6ZnIm2 exhibits a perpendicular structure consisting of two planar ZnII-porphyrins and has been characterized as a distinct open-shell diradical on the basis of its non-observable 1H NMR signals, a clear ESR signal, and a characteristic absorption spectrum reaching about 1700 nm. Despite the distinct diradical character, 6ZnIm2 is an extremely stable molecule.

DOI： 10.1002/chem.201705769

Web of Science

Scopus

A meso-meso - - Triply Linked Subporphyrin Dimer 査読有り

Yasuhiro Okuda, Norihito Fukui, Jinseok Kim, Taeyeon Kim, Hua-Wei Jiang, Graeme Copley, Masaaki Kitano, Dongho Kim, Atsuhiro Osuka

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION 56 巻 ( 40 ) 頁： 12317 - 12321 2017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：WILEY-V C H VERLAG GMBH

A meso-meso - - triply linked subporphyrin dimer 6 was synthesized by stepwise reductive elimination of -to- doubly Pt-II-bridged subporphyrin dimer 9. Dimer 6 was characterized by spectroscopic and electrochemical measurements, theoretical calculations, and picosecond time-resolved transient absorption spectroscopy. X-ray diffraction analysis reveals that 6 has a bowl-shaped structure with a positive Gaussian curvature. Despite the curved structure, 6 exhibits a remarkably red-shifted absorption band at 942nm and a small electrochemical HOMO-LUMO gap (1.35eV), indicating an effectively conjugated -electronic network.

DOI： 10.1002/anie.201707123

Web of Science

Diphenylphosphine-Oxide-Fused and Diphenylphosphine-Fused Porphyrins: Synthesis, Tunable Electronic Properties, and Formation of Cofacial Dimers 査読有り

Keisuke Fujimoto, Yuko Kasuga, Norihito Fukui, Atsuhiro Osuka

CHEMISTRY-A EUROPEAN JOURNAL 23 巻 ( 28 ) 頁： 6741 - 6745 2017年5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：WILEY-V C H VERLAG GMBH

Diphenylphosphine-oxide-fused Ni-II porphyrin 8 was synthesized from 3,5,7-trichloroporphyrin 5 via a reaction sequence of nucleophilic aromatic substitution with lithium diphenylphosphide, oxidation with H2O2, and palladium-catalyzed intramolecular cyclization. Reduction of 8 with HSiCl3 gave diphenylphosphine-fused Ni-II porphyrin 9. The embedded P=O and P moieties serve as a strong electron-accepting and electron-donating group to perturb the optical and electrochemical properties of the Ni-II porphyrin. Ni-II porphyrin 9 is diamagnetic with a low-spin Ni-II center in solution but becomes paramagnetic with a five-coordinated Ni-II center with high-spin (S=1) state in the solid state. Diphenylphosphine-oxide-fused Zn-II porphyrin 10 was also synthesized and shown to form a face-to-face dimer with mutual O-Zn bonds in the crystal and in nonpolar and moderately polar solvents. The dimerization of 10 in CDCl3 has been revealed to be an entropy-driven process with a large entropy gain (S-D=207JK(-1)mol(-1)).

DOI： 10.1002/chem.201700909

Web of Science

Aromatic Metamorphosis of Dibenzofurans into Triphenylenes Starting with Nickel-Catalyzed Ring-Opening C-O Arylation 査読有り

Yuto Kurata, Shinya Otsuka, Norihito Fukui, Keisuke Nogi, Hideki Yorimitsu, Atsuhiro Osuka

ORGANIC LETTERS 19 巻 ( 6 ) 頁： 1274 - 1277 2017年3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：AMER CHEMICAL SOC

A new class of aromatic metamorphosis has been developed in which dibenzofurans were converted into triphenylenes. This transformation is composed of three successive operations: (1) nickel-catalyzed ring-opening C-O bond arylation with arylmagnesium bromides, (2) trifluoromethanesulfonylation (triflation) of the resulting hydroxy moiety with Tf2O, and (3) palladium-catalyzed or photoinduced ring closure. In the last ring-closing step, the photoinduced process has proven to be more productive than the palladium-catalyzed one. By employing pi-extended dinaphthofuran as the substrate, dorsally benzo-fused [5]helicene was obtained in a satisfactory yield.

DOI： 10.1021/acs.orglett.6b03861

Web of Science

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