＜研究概要＞
○研究テーマ
（テーマ1）有機化合物の光誘起電子移動（Photoinduced Electron Transfer: PET）反応
・アミン類を電子供与体とするカルボニル化合物およびハロゲン化物のPET反応機構解明と合成化学的展開
・シクロプロパノール誘導体のPET反応におけるラジカルカチオンの結合開裂位置選択性の支配因子解明
・電子アクセプター光増感剤と銅(II)塩の協働作用によるラジカル反応制御
（テーマ２）ベンズイミダゾリン(BIH–R)/ベンズイミダゾリウム(BI+–R)レドックス対に基づく電子移動反応
・BIH–Rの酸化過程を利用する還元的有機分子変換法の開発
・可視光吸収光増感剤とBIH–Rの協働作用によるPET反応
・可視光活性化BIH–R光試薬によるPET反応と触媒化
・ベンズイミダゾリウムアリールオキシド（ベタイン）BI+–ArO–，多環芳香族炭化水素置換体BI+–Arおよびトリアリールアミン置換体BI+–PhNAr2光触媒によるPET反応
（テーマ３）酸化還元（Reduction and Oxidation: Redox）試薬による有機電子移動反応
・ヨウ化サマリウム(II)とカルボニル化合物のRedox反応により生成するサマリウムケチルラジカルと種々の分子内官能基との反応
・連続的Redox反応：サマリウムケチルラジカルとエステルカルボニル基および炭素—ハロゲン結合の分子内反応により生成するシクロプロパノール誘導体の鉄(III)塩による酸化的開環反応
・銅(II)塩を用いる酸化反応における特異な対イオンおよび溶媒効果の原因究明とそれに基づく反応制御法の開発
・系内発生ラジカルカチオン（In-situ generated radical cation: InSRAC）法により発生させたアミンラジカルカチオンを酸化剤に用いるRedox反応
（テーマ４）グリーン酸化還元（Green Redox）反応開発（電子移動，ラジカル，他）
・上記反応のグリーン反応系への改良（安価・低毒性試薬，メタルフリー，触媒化，試薬回収再利用，反応ワンポット化など）
・有機スズ試薬非使用のための電子移動に基づく新規ラジカル反応の開発
・グリーン溶媒（イオン液体，含フッ素溶媒など）中の電子移動反応およびラジカル反応
＜参照＞
理学部コロキウム「有機光レドックス化学〜有機化学における光と酸化還元（レドックス）の協働作用〜」（2019/11/27）
○発表論文（2000年以降の主要な原著論文，総説，解説など）
[47] “Benzimidazoline（BIH）とBenzimidazolium（BI+）のレドックス化学～はじまり，開拓と広がり～ Redox Chemistry of
Benzimidazoline (BIH) and Benzimidazolium (BI+) –Initiation, Exploration and
Expansion–“, 長谷川英悦，滝沢進也，有機合成化学協会誌 2024, 82, 1001–1018.
[46] “Fluorescence Enhancement of Benzimidazolium
Derivative on Clay Nanosheets
by Surface‑Fixation Induced Emission (S‑FIE)”, H. Mori, R. Nakazato, H.
Tachibana, T. Shimada, T. Ishida, R. Miyajima, E. Hasegawa, S, Takagi, Photochem.
Photobiol. Sci. 2024, 23, 1077–1086.
[45]
“Desulfonylative Radical Truce-Smiles
Rearrangement Utilizing the Benzimidazoline and Benzimidazolium Redox Couple”, R. Miyajima, M. Okamura , K.
Oomori , H. Iwamoto , K. Wakamatsu , E. Hasegawa, Synlett 2024, 35,
352–356.
[44] “Electron
and Hydrogen Atom Donor Photocatalysts in Situ Generated from Benzimidazolium
Salts and Hydride Reagents”, R.
Miyajima, T. Kiuchi, Y. Ooe, H. Iwamoto, S. Takizawa, E. Hasegawa, J. Photochem. Photobiol. 2023,
16, 100195 (1–9).
[43] “Triarylamine-Substituted Benzimidazoliums as
Electron Donor–Acceptor Dyad-Type Photocatalysts for Reductive Organic
Transformations”, R. Miyajima, Y. Ooe, T. Miura, T. Ikoma, H.
Iwamoto, S. Takizawa, E. Hasegawa, J. Am. Chem. Soc. 2023, 145, 10236–10248.（新潟大学プレスリリース）(Niigata Univ HP)
[42] “還元的有機分子変換のための有機光レドックス触媒− Organic Photoredox Catalysts for Reductive
Transformations of Organic Molecules
–“, 長谷川英悦，光化学 2022, 53, 66-73.
[41] “A Photocatalytic System Composed of Benzimidazolium
Aryloxide and Tetramethylpiperidine 1‑Oxyl to Promote Desulfonylative α‑Oxyamination Reactions of
α‑Sulfonylketones”,
T. Tanaka, T. Kiuchi, Y. Ooe, H. Iwamoto, S.
Takizawa, S. Murata, E. Hasegawa, ACS Omega 2022, 7, 4655−4666.
[40] “Competitive
Desulfonylative Reduction and Oxidation of α‑Sulfonylketones Promoted
by Photoinduced Electron Transfer
with 2‑Hydroxyaryl-1,3-dimethylbenzimidazolines under Air”, E. Hasegawa, S. Nakamura, K. Oomori, T. Tanaka, H. Iwamoto, K.
Wakamatsu, J. Org. Chem. 2021, 86, 2556−2569.
[39] “Sterically Regulated α‑Oxygenation of α‑Bromocarbonyl Compounds Promoted Using 2‑Aryl-1,3-dimethylbenzimidazolines
and Air”, E. Hasegawa, N. Yoshioka, T. Tanaka, T, Nakaminato, K. Oomori, T.
Ikoma, H. Iwamoto, K. Wakamatsu, ACS
Omega 2020, 5, 7651−7665.
[38] “Protocol for Visible-Light-Promoted Desulfonylation
Reactions Utilizing Catalytic Benzimidazolium Aryloxide Betaines and
Stoichiometric Hydride Donor Reagents”, E. Hasegawa, T. Tanaka, N. Izumiya, T.
Kiuchi, Y. Ooe, H. Iwamoto, S. Takizawa, S. Murata, J. Org. Chem. 2020,
85, 4344−4353.
[37] “Visible Light and Hydroxynaphthylbenzimidazoline
Promoted Transition-Metal-Catalyst-Free Desulfonylation of N-Sulfonylamides and N-Sulfonylamines”, E. Hasegawa, Y.
Nagakura, N. Izumiya, K. Matsumoto, T. Tanaka, T. Miura, T.
Ikoma, H. Iwamoto, K. Wakamatsu J. Org. Chem. 2018, 83, 10813−10825.
[36]
“Benzimidazolium Naphthoxide Betaine is a Visible Light Promoted Organic Photoredox Catalyst”, E. Hasegawa, N. Izumiya, T. Miura, T. Ikoma, H. Iwamoto, S. Takizawa, S. Murata, J. Org. Chem. 2018, 83, 3921−3927.
[35] “Visible Light-Promoted Reductive Transformations of Various Organic Substances
by Using Hydroxyaryl Substituted Benzimidazolines and Bases”, E. Hasegawa, N.
Izumiya, T. Fukuda, K. Nemoto, H. Iwamoto, S. Takizawa, S. Murata, Tetrahedron 2016,
72, 7805–7812.
(Symposium-in-Print: Organic chemistry: more radical than ever
before)
[34] ”Solvent Dependent Reaction Pathways Operating in Copper(II) Tetrafluoroborate Promoted
Oxidative Ring-Opening Reactions of Cyclopropyl Silyl Ethers”, E. Hasegawa, K.
Nemoto, R. Nagumo, E. Tayama, H. Iwamoto, J. Org. Chem. 2016, 81, 2692–2703. (selected as a Featured Article with the Cover
Picture of Issue 7 )
[33] “Visible Light-Promoted Metal-Free
Reduction Reaction of Organohalides by 2-Naphthyl or 2-Hydroxylnaphthyl Substituted
1,3-Dimethylbenzimidazolines”, E. Hasegawa, K. Mori, S. Tsuji, K. Nemoto, T.
Ohta, H. Iwamoto, Aust. J. Chem. 2015, 68, 1648–1652. (A special
issue in celebration of the International Year of Light and Light-based
Technologies in 2015)
[32]
“2-Aryl-1,3-dimethylbenzimidazolines as Effective Electron and Hydrogen Donors
in Photoinduced Electron-Transfer Reactions”, E. Hasegawa, S. Takizawa, Aust. J. Chem. 2015, 68, 1640–1647. (A special issue in celebration of the International
Year of Light and Light-based Technologies in 2015)
[31] “Aryl-Substituted Dimethylbenzimidazolines
as Effective Reductants of Photoinduced Electron Transfer Reactions”, E.
Hasegawa, T. Ohta, S. Tsuji, K. Mori, K. Uchida, T. Miura, T. Ikoma, E. Tayama,
H. Iwamoto, S. Takizawa, S. Murata, Tetrahedron,
2015, 71, 5494–5505.
[30] “Metal-Free,
One-Pot, Sequential Protocol for Transforming a,b-Epoxy Ketones to b-Hydroxy Ketones and alpha-Methylene
Ketones", E. Hasegawa, S. Arai, E. Tayama, H. Iwamoto, J. Org. Chem. 2015, 80, 1593–1600.
[29] “有機光レドックス触媒は有機合成に有用か？ –光誘起電子移動反応の有機合成への応用”, 太田拓，辻詩織，長谷川英悦，化学 2014, 69, 68–69.
[28]
“光化学の事典 , 3.光化学の基礎II –有機化学 –，3.2.さまざまな光化学反応，16.光ニトロソ化”，長谷川英悦，光化学協会 光化学の事典編集委員会（編）, 朝倉書店，(2014).
[27] “A Photo-Reagent System of Benzimidazoline and Ru(bpy)3Cl2
to Promote Hexenyl Radical Cyclization and Dowd-Beckwith Ring-Expansion of a-Halomethyl Substituted Benzocyclic-1-alkanones”,
E. Hasegawa, M. Tateyama, T. Hoshi, T. Ohta, E. Tayama, H. Iwamoto, S.
Takizawa, S. Murata, Tetrahedron 2014, 70, 2776–2783.
[26] “Carbon-Carbon Bond
Formation via Benzoyl Umpolung Attained by Photoinduced Electron-Transfer with Benzimidazolines”,
T. Igarashi, E. Tayama, H. Iwamoto, E. Hasegawa, Tetrahedron Lett. 2013, 54, 6874–6877.
[25]
“Copper (II) Salt Promoted Oxidative Ring-Opening Reactions of Bicyclic Cyclopropanol
Derivatives via Radical Pathways”, E. Hasegawa, M. Tateyama, R. Nagumo, E.
Tayama, H. Iwamoto, Beilstein J. Org.
Chem. 2013, 9, 1397–1406. (Thematic
Series. Organic Free Radical Chemistry)
[24] “Photoinduced Electron-transfer Reaction of alpha-Bromomethyl-substituted Benzocyclic beta-Keto Esters with
Amines: Selective Reaction Pathways Depending on the Nature of Amine Radical
Cations”, E. Hasegawa, E. Tosaka, A. Yoneoka, Y. Tamura, S. Takizawa, M.
Tomura, Y. Yamashita, Res. Chem. Intermed. 2013, 39, 247–267.
[23] “An Effective Procedure to Promote Aza-Prins Cyclization
Reactions Employing a Combination of Ferric Chloride and an Imidazolium Salt in
Benzotrifluoride”, C. Osawa, M. Tateyama, K.
Miura, E. Tayama, H. Iwamoto, E. Hasegawa, Heterocycles
2012, 86, 1211–1226.
[22]
“Application of Biphasic Reaction Procedure Using Ferric Chloride Dissolved in
an Imidazolium Salt and Benzotrifluoride (FeIm-BTF Procedure) to Aza-Prins Cyclization
Reaction”, E. Hasegawa, N. Hiroi, C. Osawa, E. Tayama, H. Iwamoto,Tetrahedron Lett. 2010, 51, 6535–6538.
[21]
“Novel Biphasic Reaction System of Ferric Chloride Dissolved Imidazolium Hexafluorophosphate
and Benzotrifluoride: Application to Electron Transfer Reaction of Cyclopropyl Silyl
Ethers”, H. Tsuchida, E. Hasegawa, Tetrahedron
2010, 66, 3447–3451.
[20] “光誘起電子移動（PET）反応の有機合成への応用 –光増感法を用いる最近の実例より–
Application of Photoinduced Electron Transfer (PET) Reactions to Organic
Synthesis–Recent examples utilizing photosensitization procedures–“, 長谷川英悦，光化学 2010, 41, 40–44.
[19] “In Situ Generated Tris(p-bromophenyl)amine Radical Cation Promoted Electron Transfer Reaction of Cyclopropyl Silyl Ethers”, E. Hasegawa, K. Kakinuma, T. Yanaki, S. Komata, Tetrahedron 2009, 65, 10876–10881. (Symposium-in-Print: Electron transfer reagents in organic
synthesis)
[18]
“Cyclization and Ring-Expansion Processes Involving Samarium Diiodide Promoted Reductive
Formation and Subsequent Oxidative Ring-Opening of Cyclopropanol Derivatives”,
H. Tsuchida, M. Tamura, E. Hasegawa, J.
Org. Chem. 2009, 74, 2467–2475.
[17] “Benzimidazoline-Dimethoxypyrene. An Effective Promoter System
for Photoinduced Electron Transfer Promoted Reductive Transformations of Organic
Compounds”, E. Hasegawa, H. Hirose, K. Sasaki, S. Takizawa, T. Seida, N. Chiba,
Heterocycles 2009, 77, 1147–1161.
[16] “Tris(trimethylsilyl)silane Promoted Radical Reaction and Electron-Transfer
Reaction in Benzotrifluoride”, E. Hasegawa, Y. Ogawa, K. Kakinuma, H. Tsuchida,
E. Tosaka, S. Takizawa, H. Muraoka, T. Saikawa,Tetrahedron 2008, 64, 7724–7728.
[15] 日本化学会・有機化学ディビジョンレポート：12.光化学–3.電子移動–1.炭素−炭素結合形成，長谷川英悦 (2007).
[14]
“Electron Transfer Promoted Regioselective Ring-Oening Reaction of Cyclopropyl Silyl
Ethers”, E. Hasegawa, N. Yamaguchi, H. Muraoka, H. Tsuchida, Org. Lett. 2007, 9, 2811~2814.
[13]
“The First Example of Samarium Diiodide-Promoted Intramolecular Ketone-Ester Coupling
of Ketones Tethering Acyloxyalkyl Side Chains Producing 2-Hydroxy Cyclic Hemiacetals”,
E. Hasegawa, K. Okamoto, N. Tanikawa, M. Nakamura, K.Iwaya,
T. Hoshi, T. Suzuki , Tetrahedron Lett.
2006, 47, 7715–7718.
[12]
“Photoinduced Electron-Transfer Systems Consisting of Electron Donating Pyrenes
or Anthracenes and Benzimidazolines for Reductive Transformation of Carbonyl Compounds”,
E. Hasegawa, S. Takizawa, T. Seida, A. Yamaguchi, N. Yamaguchi, N. Chiba, T. Takahashi,
H. Ikeda, K. Akiyama, Tetrahedron 2006, 62, 6581–6588. (Symposium-in-Print: The chemistry of
radical ions)
[11]
“Cyclization and Ring-Expansion Reactions Involving Reductive Formation and
Oxidative Ring-Opening of Cyclopropanol Derivatives, E. Hasegawa, H. Tsuchida,
M. Tamura”, Chem. Lett. 2005, 34, 1688–1689.
[10]
“Contrastive Photoreduction Pathways of Benzophenones Governed by Regiospecific
Deprotonation of Imidazoline Radical Cations and Additive Effects”, E.
Hasegawa, T. Seida, N. Chiba, T. Takahashi, H. Ikeda, J. Org. Chem. 2005, 70,
9632–9635.
[9]
“2-Hydroxyphenyl-1,3-dimethylbenzimidazolines: Formal Two Hydrogen Atom-Donors
for Photoinduced Electron Transfer Reactions”, E. Hasegawa,
N. Chiba, T. Takahashi, S. Takizawa, T. Kitayama, T. Suzuki ,
Chem. Lett. 2004, 33, 18–19.
[8]
“Photoinduced Electron Transfer Reactions of Oxiranes and Epoxy Ketones”, E.
Hasegawa, M. Kamata, in CRC Handbook of
Organic Photochemistry and Photobiology, 2nd Ed. Horspool, W. M.
and Lenci, F., Eds., CRC Press, Boca Raton, 2004, Chapter 53, 1–17.
[7]
“Novel Transformation of 2-Substituted Alkyl 1-Indanone-2-acetates to
6-Substituted 3,4-Benzotropolones through Sequential Reduction and Oxidation
Processes using Sm(II) and Ce(IV) Salts”, K. Iwaya, M.
Tamura, M. Nakamura, E. Hasegawa, Tetrahedron
Lett. 2003, 44, 9317–9320.
[6]
“Characteristic Reactivities of Some Rearrangeable Ketyl Radicals Generated
through Photoinduced Electron Transfer Processes”, E. Hasegawa, J. Photosci. 2003, 10, 61–69.
[5] “光誘起電子移動（PET）反応を利用する有機合成 −PET反応は有機合成化学にとって魅力的か？−
Organic Synthesis Utilizing Photoinduced Electron Transfer (PET) Reactions –Are
PET Reactions Attractive to Synthetic Organic Chemistry ?
–“, 長谷川英悦，光化学 2002, 33, 220–222.
[4]
“Changeable Reactivity of Ketyl Radicals Derived from 2-Bromomethyl-2-(3-butenyl)benzocyclic-1-alkanones Depending on Electron
Transfer Conditions Employed”, E. Hasegawa, S. Takizawa, K. Iwaya, M. Kurokawa,
N. Chiba, K. Yamamichi, J. Chem. Soc.,
Chem. Commun. 2002, 1666–1667.
[3]
“Samarium Diiodide-Promoted Intramolecular Ketone-Ester Coupling Reaction:
Novel Cyclization and Ring Expansion Pathway”, K. Iwaya, M. Nakamura, E.
Hasegawa, Tetrahedron Lett. 2002, 43, 5067–5070.
[2]
“1,3-Dimethyl-2-phenylbenzimidazoline (DMPBI)-Acetic Acid: An Effective Reagent
System for Photoinduced Reductive Transformation of a,b-Epoxy Ketones to b-Hydroxy Ketones”,
E. Hasegawa, N. Chiba, A. Nakajima, K. Suzuki, A. Yoneoka, K. Iwaya, Synthesis 2001, 1248–1252.
[1]
“Reaction of Ethyl 2-Haloethyl-1-tetralone-2-carboxylate and Samarium Diiodide:
First Example of Intramolecular O-Alkylation of Samarium Ketyl Radical by
Carbon-Halogen Bond”, E. Hasegawa, K. Iwaya, T. Iriyama, T. Kitazume, M.
Tomura, Y. Yamashita, Tetrahedron Lett.
2000, 41, 6447–6450.
○その他
[5] “異分野融合と天地人”，長谷川英悦，有機合成化学協会誌（巻頭言），Vol. 81, No. 7, p. 667
(2023).
[4] “有機合成の新潮流〜光レドックス触媒化学とは〜”，長谷川英悦，東洋クリエート「創造」, 46号, pp.14–18 (2020).
[3] “有機化学の基本—電子のやり取りから理解する“, 富岡秀雄，立木次郎，赤羽良一，長谷川英悦，平井克幸，化学同人 (2013).
[2] “新潟大学グリーンケミストリー連携教育研究センターの取組み”，長谷川英悦，GSCN-News Letter, No. 45 (2012).
[1] “基礎化学 —マンガ＋要点整理＋演習問題でわかるシリーズ —”, 齋藤勝裕，長谷川英悦, オーム社 (2012).
（最終更新日: 12/20/2024）
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