1
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Yoshida Y, Sawamura M, Shimizu Y. Boron-Catalyzed Michael Reaction of Donor-Acceptor Carboxylic Acid Pairs Enabling Direct Synthesis of 1,5-Dicarboxylic Acids. Org Lett 2024; 26:5425-5429. [PMID: 38898380 DOI: 10.1021/acs.orglett.4c01542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
A boron-catalyzed Michael reaction using pairs of carboxylic acids was developed. The reaction occurs through dual activation of the two substrates by a boron catalyst, which facilitates boron enolate formation from the donor carboxylic acid with simultaneous activation of the α,β-unsaturated carboxylic acid as the acceptor. α-Aryl and α-alkenyl carboxylic acids were applicable as donors. The versatility and utility of this reaction were demonstrated by the direct use of pharmaceuticals as donor carboxylic acids.
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Affiliation(s)
- Yukiho Yoshida
- Department of Chemistry, Faculty of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
| | - Masaya Sawamura
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo, Hokkaido 001-0021, Japan
- Department of Chemistry, Faculty of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
| | - Yohei Shimizu
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo, Hokkaido 001-0021, Japan
- Department of Chemistry, Faculty of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
- List Sustainable Digital Transformation Catalyst Collaboration Research Platform, Institute for Chemical Reaction Design and Discovery (ICReDD List-PF), Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo, Hokkaido 001-0021, Japan
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2
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Okumatsu D, Kawanaka K, Kainuma S, Kiyokawa K, Minakata S. α-Amination of Carbonyl Compounds by Using Hypervalent Iodine-Based Aminating Reagents Containing a Transferable (Diarylmethylene)amino Group. Chemistry 2023; 29:e202203722. [PMID: 36604401 DOI: 10.1002/chem.202203722] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 01/05/2023] [Accepted: 01/05/2023] [Indexed: 01/07/2023]
Abstract
Hypervalent iodine-based aminating reagents containing a transferable (diarylmethylene)amino group can be used for the α-amination of simple carbonyl compounds such as esters, amides, and ketones in the presence of a lithium base. The (diarylmethylene)amino groups of the products can be readily modified, thus providing access to primary amines and diarylmethylamines. The developed method features transition-metal-free conditions and a simple one-pot procedure without the need to prepare enolate equivalents separately, thus offering a general and practical approach to the synthesis of a wide variety of α-amino carbonyl compounds. Experimental mechanistic investigations indicate that this amination proceeds through a unique radical coupling of an α-carbonyl radical with an iminyl radical; they are generated through a single-electron transfer between a lithium enolate and the hypervalent iodine reagent.
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Affiliation(s)
- Daichi Okumatsu
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka, 565-0871, Japan
| | - Kazuki Kawanaka
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka, 565-0871, Japan
| | - Shunpei Kainuma
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka, 565-0871, Japan
| | - Kensuke Kiyokawa
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka, 565-0871, Japan
| | - Satoshi Minakata
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka, 565-0871, Japan
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3
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Wu X, Li Y, Hu H. The Enediolate Chemistry of Free Carboxylic Acids. Chem Asian J 2023; 18:e202201113. [PMID: 36583337 DOI: 10.1002/asia.202201113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 12/25/2022] [Accepted: 12/28/2022] [Indexed: 12/31/2022]
Abstract
The synthetic methodologies for the α-functionalization of free carboxylic acids through the enediolate intermediates are summarized in this review. In general, the enediolates could be generated in situ or transiently from free carboxylic acids with a stoichiometric or catalytic amount of protection reagents, including metal, boron, and silicon reagents. The in situ or transient generated enediolates were subsequently subjected to racemic or asymmetric reactions with various electrophiles, producing the α-functionalized free carboxylic acids in a single step. In addition, the enediolate could undergo an α-oxidation reaction with TEMPO through the radical process.
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Affiliation(s)
- Xin Wu
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, 610068, China
| | - Yang Li
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, 610068, China
| | - Haipeng Hu
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, 610068, China.,College of Science Sichuan, Agricultural University, Ya'an, Sichuan, 625014, P.R. China
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4
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Suzuki H, Kondo S, Yamada K, Matsuda T. Diastereo- and Enantioselective Reductive Mannich-type Reaction of α,β-Unsaturated Carboxylic Acids to Ketimines: A Direct Entry to Unprotected β 2,3,3 -Amino Acids. Chemistry 2023; 29:e202202575. [PMID: 36341524 PMCID: PMC10107894 DOI: 10.1002/chem.202202575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 11/05/2022] [Accepted: 11/07/2022] [Indexed: 11/09/2022]
Abstract
Stereoselective construction of unprotected β-amino acids is a significant challenge owing to the lack of methods for the catalytic generation of highly enantioenriched carboxylic acid enolates. In this study, a novel copper-catalyzed diastereo- and enantioselective reductive Mannich-type reaction of α,β-unsaturated carboxylic acids was developed, which provides a direct and scalable synthetic method for enantioenriched β2,3,3 -amino acids with vicinal stereogenic centers. The protocol features in situ generation of transiently protected carboxylic acids by a hydrosilane and their diastereo- and enantioselective reductive coupling with ketimines. The synthetic utility of this process was demonstrated by a gram-scale reaction and the transformation of β-amino acids.
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Affiliation(s)
- Hirotsugu Suzuki
- Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagrazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Sora Kondo
- Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagrazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Koichiro Yamada
- Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagrazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Takanori Matsuda
- Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagrazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
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5
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Shimizu Y, Kanai M. Boron-Catalyzed α-Functionalizations of Carboxylic Acids. CHEM REC 2023:e202200273. [PMID: 36639245 DOI: 10.1002/tcr.202200273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 12/24/2022] [Indexed: 01/15/2023]
Abstract
Catalytic, chemoselective, and asymmetric α-functionalizations of carboxylic acids promise up-grading simple feedstock materials to value-added functional molecules, as well as late-stage structural diversifications of multifunctional molecules, such as drugs and their leads. In this personal account, we describe boron-catalyzed α-functionalizations of carboxylic acids developed in our group (five reaction types). The reversible boron carboxylate formation is key to the acidification of the α-protons and enolization using mild organic bases, allowing for chemoselective and asymmetric bond formations of carboxylic acids. The ligand effects on reactivity and stereoselectivity, substrate scopes, and mechanistic insights are summarized.
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Affiliation(s)
- Yohei Shimizu
- Department of Chemistry, Faculty of Sciences Hokkaido University, Kita 10 Nishi 8, 060-0810, Kita-ku, Sapporo, Hokkaido, Japan.,Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Kita 10 Nishi 8, 001-0021, Kita-ku, Sapporo, Hokkaido, Japan
| | - Motomu Kanai
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, 113-0033, Tokyo, Japan
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6
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Li HC, Li GN, Sun K, Chen XL, Jiang MX, Qu LB, Yu B. Ce(III)/Photoassisted Synthesis of Amides from Carboxylic Acids and Isocyanates. Org Lett 2022; 24:2431-2435. [DOI: 10.1021/acs.orglett.2c00699] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Hao-Cong Li
- Green Catalysis Center, College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
| | - Guan-Nan Li
- Green Catalysis Center, College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
| | - Kai Sun
- Green Catalysis Center, College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
| | - Xiao-Lan Chen
- Green Catalysis Center, College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
| | - Ming-Xuan Jiang
- Green Catalysis Center, College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
| | - Ling-Bo Qu
- Green Catalysis Center, College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
| | - Bing Yu
- Green Catalysis Center, College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
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7
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Hu H, wang C, Wu X, Liu Y, Yue G, su G, Feng J. Boron-Catalyzed alfa-C-H Fluorination of Aryl Acetic Acids. Org Chem Front 2022. [DOI: 10.1039/d1qo01814k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The catalytic alfa-C-H fluorination of aryl acetic acid was achieved with good functional tolerance in the presence of a boron catalyst. A series of alfa-fluoro aryl acetic acids was obtained...
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8
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Boron compounds for catalytic applications. ADVANCES IN CATALYSIS 2022. [DOI: 10.1016/bs.acat.2022.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Suzuki H, Yoneoka K, Kondo S, Matsuda T. Copper-Catalyzed Enantioselective Reductive Aldol Reaction of α,β-Unsaturated Carboxylic Acids to Ketones: Silanes as Activator and Transient Protecting Group. Chemistry 2021; 28:e202104273. [PMID: 34967961 DOI: 10.1002/chem.202104273] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Indexed: 11/09/2022]
Abstract
We have developed the first enantioselective reductive aldol reaction of unprotected α,β-unsaturated carboxylic acids by employing a copper/bisphosphine catalyst. The reaction features in situ protection and activation of an α,β-unsaturated carboxylic acid by a hydrosilane. The copper enolate formed in situ reacts with a ketone to afford the β-hydroxy carboxylic acid with excellent enantioselectivity (up to 99% ee). The corresponding gram-scale reaction with a low catalyst loading and the derivatization of the β-hydroxy carboxylic acids highlight the practicality of this transformation.
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Affiliation(s)
- Hirotsugu Suzuki
- Tokyo University of Science: Tokyo Rika Daigaku, Department of Applied Chemistry, 1-3 Kagurazaka, Shinjuku-ku, 162-8601, Tokyo, JAPAN
| | - Kenji Yoneoka
- Tokyo University of Science: Tokyo Rika Daigaku, Department of Applied Chemistry, 1-3 Kagurazaka, Shinjuku-ku, 162-8601, Tokyo, JAPAN
| | - Sora Kondo
- Tokyo University of Science: Tokyo Rika Daigaku, Department of Applied Chemistry, 1-3 Kagurazaka, Shinjuku-ku, 162-8601, Tokyo, JAPAN
| | - Takanori Matsuda
- Tokyo University of Science, Department of Applied Chemistry, 1-3 Kagurazaka, Shinjuku, 162-8601, Tokyo, JAPAN
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10
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Niu R, He Y, Lin JB. Catalytic asymmetric synthesis of α-stereogenic carboxylic acids: recent advances. Org Biomol Chem 2021; 20:37-54. [PMID: 34854454 DOI: 10.1039/d1ob02038b] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Chiral carboxylic acids bearing an α-stereogenic center constitute the backbone of many natural products and therapeutic reagents as well as privileged chiral ligands and catalysts. Hence, it is not surprising that a large number of elegant catalytic asymmetric strategies have been developed toward the efficient synthesis of α-chiral carboxylic acids, such as α-hydroxy acids and α-amino acids. In this review, the recent advances in asymmetric synthesis of α-stereogenic free carboxylic acids via organocatalysis and transition metal catalysis are summarized (mainly from 2010 to 2020). The content is organized by the reaction type of the carboxyl source involved, including asymmetric functionalization of substituted carboxylic acids, cyclic anhydrides, α-keto acids, substituted α,β-unsaturated acids and so on. We hope that this review will motivate further interest in catalytic asymmetric synthesis of chiral α-substituted carboxylic acids.
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Affiliation(s)
- Rui Niu
- Shaanxi Key Laboratory of Chemical Reaction Engineering, College of Chemistry and Chemical Engineering, Yan'an University, Yan'an 716000, China.
| | - Yi He
- Shaanxi Key Laboratory of Chemical Reaction Engineering, College of Chemistry and Chemical Engineering, Yan'an University, Yan'an 716000, China.
| | - Jun-Bing Lin
- Shaanxi Key Laboratory of Chemical Reaction Engineering, College of Chemistry and Chemical Engineering, Yan'an University, Yan'an 716000, China.
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11
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Tanaka R, Hirata Y, Kojima M, Yoshino T, Matsunaga S. Cp*Rh(III)/boron hybrid catalysis for directed C-H addition to β-substituted α,β-unsaturated carboxylic acids. Chem Commun (Camb) 2021; 58:76-79. [PMID: 34874388 DOI: 10.1039/d1cc05956d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The C-H bond addition reaction of 2-phenylpyridine derivatives with α,β-unsaturated carboxylic acids catalyzed by Cp*Rh(III)/BH3·SMe2 is reported. Activation of C-H bonds with the rhodium catalyst and activation of α,β-unsaturated carboxylic acids with the boron catalyst cooperatively work, and a BINOL-urea hybrid ligand significantly improved the reactivity. With the optimized hybrid catalytic system, various β-disubstituted carboxylic acids were obtained under mild reaction conditions.
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Affiliation(s)
- Ryo Tanaka
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.
| | - Yuki Hirata
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.
| | - Masahiro Kojima
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.
| | - Tatsuhiko Yoshino
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan. .,Global Station for Biosurfaces and Drug Discovery, Hokkaido University, Sapporo 060-0812, Japan
| | - Shigeki Matsunaga
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan. .,Global Station for Biosurfaces and Drug Discovery, Hokkaido University, Sapporo 060-0812, Japan
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12
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Nishino S, Miura M, Hirano K. An umpolung-enabled copper-catalysed regioselective hydroamination approach to α-amino acids. Chem Sci 2021; 12:11525-11537. [PMID: 34567503 PMCID: PMC8409476 DOI: 10.1039/d1sc03692k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 07/27/2021] [Indexed: 01/03/2023] Open
Abstract
A copper-catalysed regio- and stereoselective hydroamination of acrylates with hydrosilanes and hydroxylamines has been developed to afford the corresponding α-amino acids in good yields. The key to regioselectivity control is the use of hydroxylamine as an umpolung, electrophilic amination reagent. Additionally, a judicious choice of conditions involving the CsOPiv base and DTBM-dppbz ligand of remote steric hindrance enables the otherwise challenging C-N bond formation at the α position to the carbonyl. The point chirality at the β-position is successfully controlled by the Xyl-BINAP or DTBM-SEGPHOS chiral ligand with similarly remote steric bulkiness. The combination with the chiral auxiliary, (-)-8-phenylmenthol, also induces stereoselectivity at the α-position to form the optically active unnatural α-amino acids with two adjacent stereocentres.
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Affiliation(s)
- Soshi Nishino
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University Suita Osaka 565-0871 Japan
| | - Masahiro Miura
- Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University Suita Osaka 565-0871 Japan
| | - Koji Hirano
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University Suita Osaka 565-0871 Japan
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13
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Sun K, Ueno M, Imaeda K, Ueno K, Sawamura M, Shimizu Y. Visible-Light-Driven α-Allylation of Carboxylic Acids. ACS Catal 2021. [DOI: 10.1021/acscatal.1c02558] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Kai Sun
- Department of Chemistry, Faculty of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
| | - Masato Ueno
- Department of Chemistry, Faculty of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
| | - Keisuke Imaeda
- Department of Chemistry, Faculty of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
| | - Kosei Ueno
- Department of Chemistry, Faculty of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
| | - Masaya Sawamura
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo, Hokkaido 001-0021, Japan
- Department of Chemistry, Faculty of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
| | - Yohei Shimizu
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo, Hokkaido 001-0021, Japan
- Department of Chemistry, Faculty of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
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14
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Yazaki R. Development of Catalytic Reactions for Precise Control of Chemoselectivity. Chem Pharm Bull (Tokyo) 2021; 69:516-525. [PMID: 34078797 DOI: 10.1248/cpb.c21-00092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Catalytic chemoselective reactions of innately less reactive functionalities over more reactive functionalities are described. A cooperative catalyst comprising a soft Lewis acid/hard Brønsted base enabled chemoselective activation of a hydroxyl group over an amino group, allowing for nucleophilic addition to electron-deficient olefins. The reaction could be applicable for a variety of amino alcohols, including pharmaceuticals, without requiring a tedious protection-deprotection process. Chemoselective enolization and subsequent α-functionalization of carboxylic acid derivatives were also achieved by a redox active catalyst through the radical process, providing unnatural α-amino/hydroxy acid derivatives bearing a complex carbon framework and a diverse set of functionalities. The present chemoselective catalysis described herein offers new opportunities to expand the chemical space for innovative drug discovery research.
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Affiliation(s)
- Ryo Yazaki
- Graduate School of Pharmaceutical Sciences, Kyushu University
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15
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Mahato SK, Ohara N, Khake SM, Chatani N. Iridium(III)-Catalyzed Direct Intermolecular Chemoselective α-Amidation of Masked Aliphatic Carboxylic Acids with Dioxazolones via Nitrene Transfer. ACS Catal 2021. [DOI: 10.1021/acscatal.1c01901] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Sanjit K. Mahato
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | - Nozomi Ohara
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | - Shrikant M. Khake
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | - Naoto Chatani
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
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