論文 - 堤　亮祐

DiazaChrysenes (DC): Nitrogen-Containing π-Extended Molecules for Photocatalytic C–H Amination

Xu W., Iwai A., Nagasaka I., Watanabe S., Tsutsumi R., Kumagai N.

Organic Letters 27 （ 39 ） 10937 - 10942 2025年10月

研究論文（学術雑誌）, 査読有り,  ISSN  15237060

　概要を見る

We report a new class of nitrogen-containing π-extended heterocycles, DiazaChrysenes (DCs), and their dimeric analogues (dDCs) as metal-free photocatalysts for C–H amination. DCs featuring a quinolino[1,2-c]quinazolin-5-ium core were synthesized via electrophilic amide activation and arylation. The resulting compounds displayed tunable photophysical and redox properties, with CF<inf>3</inf>-substituted DCs enabling the C–H amination of arenes with azoles under visible light and aerobic conditions, achieving yields up to 85%. The reaction tolerated a range of arene and azole substrates without requiring metal salts or additives. In contrast, dDCs exhibited diminished activity, likely due to their extended π-curvature. Computational studies, including NCI, ACID, and NICS analyses, revealed locally aromatic but electronically isolated π-systems and deshielded central 8-membered cores. This work highlights the utility of DC scaffolds as synthetically accessible and redox-tunable organic photocatalysts.

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Enlarged-TriQuinoline (Enl-TQ): Disparity in Chemical Behaviors by Geometric Scaling of the Trimeric Quinoline Ring System

Yamashita M., Tsutsumi R., Kobayashi T., Kumagai N.

Chemistry an Asian Journal 20 （ 17 ）  2025年09月

研究論文（学術雑誌）, 査読有り,  ISSN  18614728

　概要を見る

TriQuinoline (TQ), a quasi-planar cyclic quinoline trimer concatenated at the 2,8-positions in a head-to-tail arrangement, strongly captures a proton at the 12-membered inner cycle and exhibits unusual physicochemical properties, including unexpected water solubility and the ability to engage in complexation with other π-conjugated molecules. In this study, we designed and synthesized its expanded analog, coined Enlarged-TriQuinoline (Enl-TQ), in which three alkyne units are embedded between three quinoline units to acquire an expanded planar 18-membered ring system. DFT calculations and X-ray crystallographic analysis revealed its planar architecture with three inwardly facing pyridinic nitrogen atoms. Despite its structural similarity to TQ, Enl-TQ displayed distinct host capability and photophysical characteristics.

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Expeditious Access to the B3NO2 Heterocycle Enabling Modular Derivatization

Tsutsumi R., Kashiwagi N., Kumagai N.

The Journal of Organic Chemistry （Journal of Organic Chemistry）  88 （ 9 ） 6247 - 6251 2023年05月

研究論文（学術雑誌）, 共著, 筆頭著者, 査読有り,  ISSN  00223263

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DATB (1,3-dioxa-5-aza-2,4,6-triborinane) is a unique six-membered heterocycle exhibiting proficient catalytic activity in direct dehydrative amidation. Reported herein is an improved synthetic protocol for DATB derivatives featuring a concise two-step chromatography-free process. Suzuki-Miyaura coupling assembled 2,6-dibromoaniline derivatives and 1,2-phenylenediboronic acid to afford dimeric B-spiroborate salts. Acidic untying of the spiroborates gave rise to the DATB ring system with various substituents.

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Azo-tagged C4N4 fluorophores: unusual overcrowded structures and their application to fluorescent imaging

Kohei M., Takizawa N., Tsutsumi R., Xu W., Kumagai N.

Organic & Biomolecular Chemistry （Organic and Biomolecular Chemistry）  21 （ 14 ） 2889 - 2893 2023年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  14770520

　概要を見る

The C4N4 fluorophore is an intense fluorescence emitter featuring a 2,5-diaminopyrimidine core comprising four carbon and four nitrogen atoms. A series of C4N4 derivatives was photochemically dimerized at the 5-amino group, furnishing overcrowded orthotetraaryl-substituted diaryl azo compounds with a characteristic skewed structure revealed by X-ray crystallography. The photo-quenched azo-C4N4s are useful for fluorescently visualizing cells under hypoxic conditions.

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Chiral Bipyridine Ligand with Flexible Molecular Recognition Site: Development and Application to Copper‐Catalyzed Asymmetric Borylation of α,β‐Unsaturated Ketones

Ryosuke Tsutsumi, Rika Taguchi, Masahiro Yamanaka

ChemCatChem （Wiley）  14 （ 2 ） e202101278 2021年10月

研究論文（学術雑誌）, 共著, 筆頭著者, 査読有り,  ISSN  1867-3880

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Mechanistic insights into entropy-driven 1,2-type Friedel-Crafts reaction with conformationally flexible guanidine-bisthiourea bifunctional organocatalysts

Katsuhiro Nakano and Tatsuya Orihara and Masaki Kawaguchi and Keisuke Hosoya and Shogo Hirao and Ryosuke Tsutsumi and Masahiro Yamanaka and Minami Odagi and Kazuo Nagasawa

Tetrahedron （Elsevier {BV}）  92   132281 - 132281 2021年07月

研究論文（学術雑誌）, 共著, 査読有り

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Catalyst-Dependent Rate-Determining Steps in Regiodivergent Vinylogous Aza-Morita-Baylis-Hillman Reactions with N-Ts Imines

Gondo N., Hyakutake R., Fujimura K., Ueda Y., Nakano K., Tsutsumi R., Yamanaka M., Kawabata T.

Asian Journal of Organic Chemistry （Asian Journal of Organic Chemistry）  11 （ 3 ）  2021年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  21935807

　概要を見る

Catalyst-controlled vinylogous aza-MBH reactions of vinylcyclopentenone were performed, and it was found that the α-adducts were exclusively obtained by DABCO-catalysis, while the γ-adducts were the major products by DMAP-catalysis. We report here that the rate-determining step of the DABCO-catalyzed α-selective reactions is the Mannich-type C−C bond forming step, while that of the DMAP-catalyzed γ-selective reactions seems to be the β-elimination step.

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Enantioselective Epoxidation of 2,3-Disubstituted Naphthoquinones by a Side Chain Truncated Guanidine–Urea Bifunctional Organocatalyst

Tatsuya Orihara and Masaki Kawaguchi and Keisuke Hosoya and Ryosuke Tsutsumi and Masahiro Yamanaka and Minami Odagi and Kazuo Nagasawa

The Journal of Organic Chemistry （American Chemical Society ({ACS})）  85 （ 23 ） 15232 - 15240 2020年12月

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  0022-3263

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Arylation of aryllithiums with S-arylphenothiazinium ions for biaryl synthesis

Tatsuya Morofuji and Tatsuki Yoshida and Ryosuke Tsutsumi and Masahiro Yamanaka and Naokazu Kano

Chemical Communications （Royal Society of Chemistry ({RSC})）  56 （ 90 ） 13995 - 13998 2020年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  1359-7345

　概要を見る

<p>Aryllithiums were arylated with <italic>S</italic>-arylphenothiazinium ions through selective ligand coupling of intermediary sulfuranes. Various unsymmetrical biaryls were obtained without transition-metal catalysis.</p>

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Catalytic asymmetric fluorination using CSF sparingly soluble in organic solvent

Tsutsumi R.

Yuki Gosei Kagaku Kyokaishi/Journal of Synthetic Organic Chemistry （Yuki Gosei Kagaku Kyokaishi/Journal of Synthetic Organic Chemistry）  78 （ 2 ） 158 - 159 2020年

ISSN  00379980

　概要を見る

Metal fluorides such as KF and CsF are inexpensive and easy-to-handle nucleophilic fluorinating reagents while their insolubility in most organic solvents often causes a problem in their synthetic use. In this review, examples of nucleophilic fluorination promoted by a hydrogen-bonding donor are described. Moreover, a recent research on asymmetric nucleophilic fluorination using a chiral hydrogen-bond donor catalyst is introduced.

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Enantioselective Friedel–Crafts Alkylation Reaction of Indoles with α-Trifluoromethylated β-Nitrostyrenes Catalyzed by Chiral BINOL Metal Phosphate

Ignacio Ib{\'{a}}{\~{n}}ez and Mio Kaneko and Yuto Kamei and Ryosuke Tsutsumi and Masahiro Yamanaka and Takahiko Akiyama

ACS Catalysis （American Chemical Society ({ACS})）  9 （ 8 ） 6903 - 6909 2019年08月

研究論文（学術雑誌）, 共著, 査読有り

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Catalysis Based on C−I⋅⋅⋅π Halogen Bonds: Electrophilic Activation of 2‐Alkenylindoles by Cationic Halogen‐Bond Donors for [4+2] Cycloadditions

Satoru Kuwano and Takumi Suzuki and Masahiro Yamanaka and Ryosuke Tsutsumi and Takayoshi Arai

Angewandte Chemie International Edition （Wiley）  58 （ 30 ） 10220 - 10224 2019年07月

研究論文（学術雑誌）, 共著, 査読有り

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Diastereoselective Synthesis of CF3-Substituted Spiroisochromans by [1,5]-Hydride Shift/Cyclization/Intramolecular Friedel–Crafts Reaction Sequence

Risa Tamura and Eriko Kitamura and Ryosuke Tsutsumi and Masahiro Yamanaka and Takahiko Akiyama and Keiji Mori

Organic Letters （American Chemical Society ({ACS})）  21 （ 7 ） 2383 - 2387 2019年04月

研究論文（学術雑誌）, 共著, 査読有り

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Enantioselective Electrophilic Cyanation of Boron Enolates: Scope and Mechanistic Studies

Takaya Nagata, Atsuko Tamaki, Kensuke Kiyokawa, Ryosuke Tsutsumi, Masahiro Yamanaka, Satoshi Minakata

Chemistry—A European Journal （WILEY-V C H VERLAG GMBH）  24 （ 64 ） 17027 - 17032 2018年09月

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  0947-6539

　概要を見る

Chiral beta-ketonitriles bearing a stereogenic carbon center at the alpha-position are an important class of compounds, many of which serve as useful synthetic intermediates for the preparation of chiral 1,3-aminoalcohols, beta-hydroxy nitriles, and related derivatives. Although the enantioselective electrophilic cyanation of enolate equivalents is one of the most promising approaches for the synthesis of chiral beta-ketonitriles, the available methods are largely limited to reactions of 1,3-dicarbonyl compounds. Herein, we report on enantioselective electrophilic cyanation of boron enolates, which are readily prepared from alpha,beta-unsaturated ketones and diisopinocampheylborane (Ipc(2)BH) to afford chiral beta-ketonitriles with a high level of enantioselectivity. The present method is scalable and provides facile access to both enantiomers of chiral beta-ketonitriles. Analysis of the in situ generated boron enolates by NMR revealed that hydroboration proceeds in a stereospecific manner, providing alpha,alpha-disubstituted boron enolates in the form of single isomers. Furthermore, the results of DFT calculations suggest that the cyanation of the boron enolates with p-toluenesulfonyl cyanide (TsCN) proceeds in a highly enantioselective manner through a unique six-membered ring transition state.

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N-Sulfonyl α-imino ester-derived chiral oxaziridines: catalytic asymmetric synthesis and application as a modular chiral organic oxidant

Naoya Tanaka and Ryosuke Tsutsumi and Daisuke Uraguchi and Takashi Ooi

Chem. Commun. （Royal Society of Chemistry ({RSC})）  53 （ 52 ） 6999 - 7002 2017年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  1359-7345

　概要を見る

A novel class of chiral N-sulfonyl oxaziridines is introduced for use as structurally modifiable chiral oxidants. These oxaziridines are readily prepared from N-sulfonyl α-imino esters in a highly enantioenriched form by oxidation with hydrogen peroxide using l-isoleucine-derived triaminoiminophosphorane as a catalyst. The distinct advantage of their structural modularity is demonstrated through the identification of an optimal oxaziridine that exhibits high reactivity and enantiospecificity in the asymmetric oxidation of a silyl enol ether and N-sulfonyl allylic and homoallylic amines.

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Ruthenium-catalyzed C-C coupling of amino alcohols with dienes via transfer hydrogenation: Redox-triggered imine addition and related hydroaminoalkylations

Chen, T.-Y. and Tsutsumi, R. and Montgomery, T.P. and Volchkov, I. and Krische, M.J.

Journal of the American Chemical Society （Journal of the American Chemical Society）  137 （ 5 ） 1798 - 1801 2015年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  00027863

　概要を見る

Ruthenium-catalyzed hydrogen transfer from 4-aminobutanol to butadiene results in the pairwise generation of 3,4-dihydro-2H-pyrrole and an allylruthenium complex, which combine to form products of imine anti-crotylation. In couplings of 1-substituted-1,3-dienes, novel C2 regioselectivity is observed. As corroborated by deuterium labeling studies, kinetically preferred hydrometalation of the terminal olefin of the 1-substituted-1,3-diene delivers a 1,1-disubstituted π-allylruthenium complex that isomerizes to a thermodynamically more stable monosubstituted π-allylruthenium complex, which undergoes imine addition with allylic inversion through a closed transition structure. Direct ruthenium-catalyzed diene hydroaminoalkylations with pyrrolidine also are described.

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Diastereo- and Enantioselective Iridium Catalyzed Carbonyl (α-Cyclopropyl)allylation via Transfer Hydrogenation

Tsutsumi, R. and Hong, S. and Krische, M.J.

Chemistry - A European Journal （Chemistry - A European Journal）  21 （ 37 ） 12903 - 12907 2015年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  09476539

　概要を見る

The first examples of diastereo- and enantioselective carbonyl α-(cyclopropyl)allylation are reported. Under the conditions of iridium catalyzed transfer hydrogenation using the chiral precatalyst (R)-Ir-I modified by SEGPHOS, carbonyl α-(cyclopropyl)allylation may be achieved with equal facility from alcohol or aldehyde oxidation levels. This methodology provides a conduit to hitherto inaccessible inaccessible enantiomerically enriched cyclopropane-containing architectures. Alcohol solves problems: Chiral iridium catalysts modified by (R)-SEGPHOS catalyze the transfer hydrogenative coupling of racemic α-cyclopropyl allyl acetate with diverse primary alcohols with good anti-diastereo- and exceptional enantioselectivity. These processes represent the first diastereo- and enantioselective carbonyl (α-cyclopropyl)allylations.

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キラルトリアミノイミノホスホランを触媒とする不斉ペイン型酸化反応の開発

堤 亮祐

名古屋大学 2014年03月

The practical preparation of chiral N-sulfonyl oxaziridines via catalytic asymmetric payne oxidation

Tsutsumi, R. and Kim, S. and Uraguchi, D. and Ooi, T.

Synthesis (Germany) （Synthesis (Germany)）  46 （ 7 ） 871 - 878 2014年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  0039-7881

　概要を見る

触媒的不斉Payne型酸化による光学活性N-スルホニルオキサジリジン合成法を開発した。適切な反応条件を設定することで、種々のN-スルホニルアルジミンを基質として、酸化反応が効率的かつ高エナンチオ選択的に進行する。

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Catalytic asymmetric Payne oxidation under the catalysis of P-spiro chiral triaminoiminophosphorane: Application to the synthesis of N-sulfonyl oxaziridines

Uraguchi, D. and Tsutsumi, R. and Ooi, T.

Tetrahedron （PERGAMON-ELSEVIER SCIENCE LTD）  70 （ 8 ） 1691 - 1701 2014年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  0040-4020

　概要を見る

The studies on the development of a highly enantioselective oxidation of N-sulfonyl imines with hydrogen peroxide-trichloroacetonitrile system utilizing P-spiro chiral triaminoiminophosphoranes as an organic base catalyst are detailed. This method is general and scalable, and exhibits unique chemo-selectivity, providing a practical stereoselective route to structurally diverse N-sulfonyl oxaziridines. The mechanistic investigations reveal that the reaction proceeds through the Payne-type oxidation pathway. The synthetic utility of the optically active N-sulfonyl oxaziridines as versatile organic oxidants and chiral building blocks is also demonstrated. (C) 2014 Elsevier Ltd. All rights reserved.

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