1
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Sennari G, Yamagishi H, Sarpong R. Remote C-H Amination and Alkylation of Camphor at C8 through Hydrogen-Atom Abstraction. J Am Chem Soc 2024; 146:7850-7857. [PMID: 38447162 DOI: 10.1021/jacs.4c01351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2024]
Abstract
Camphor continues to serve as a versatile chiral building block for chemical synthesis. We have developed a novel method to functionalize the camphor skeleton at C8 using an intramolecular hydrogen atom abstraction. The key advance involves the use of a camphor-derived aminonitrile, which is converted to the corresponding nitrogen-centered radical under photoredox conditions to effect the 1,5-hydrogen atom transfer at C8. The resulting carbon-centered radical at C8 was utilized in a C-H amination to access topologically complex proline derivatives. Furthermore, the total synthesis of several sesquiterpenoids was accomplished by engaging the radical generated at C8 in alkylation reactions.
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Affiliation(s)
- Goh Sennari
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- O̅mura Satoshi Memorial Institute and Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Hiroki Yamagishi
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Richmond Sarpong
- Department of Chemistry, University of California, Berkeley, California 94720, United States
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2
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Xu Y, Wang B, Wang J, Zhou X, Chen J, Guo X, Deng GJ, Shao W. Regioselective Synthesis of Unsymmetrical Vicinal Diamines via Azidoimination of Alkenes with TMSN 3 and Ketimines. Org Lett 2023. [PMID: 37991479 DOI: 10.1021/acs.orglett.3c03642] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2023]
Abstract
2-Azidoimines are versatile precursors to value-added vicinal unsymmetrical diamines, which are among the most common motifs in biologically active compounds. Herein, we report their operationally simple synthesis through a highly regioselective intermolecular azidoamination of olefins under metal-free conditions. The approach proceeded through azide and iminyl, two differentiated N-centered radicals. The synthetic potential of the protocols was further established via the condensation/amination sequential cascade and chemoselective, orthogonal transformations to access vicinal primary diamines.
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Affiliation(s)
- Yongzhuo Xu
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, P. R, China
| | - Boqiang Wang
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, P. R, China
| | - Jiajia Wang
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, P. R, China
| | - Xuan Zhou
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, P. R, China
| | - Jiaxing Chen
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, P. R, China
| | - Xinjia Guo
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, P. R, China
| | - Guo-Jun Deng
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, P. R, China
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, P. R, China
| | - Wen Shao
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, P. R, China
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3
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Ghosh SK, He L, Tang Z, Comito RJ. Selective and Functional-Group-Tolerant Photoalkylation of Imines by Energy-Transfer Photocatalysis. J Org Chem 2023; 88:15209-15217. [PMID: 37875007 DOI: 10.1021/acs.joc.3c01722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2023]
Abstract
Basic amines show broad bioactivity and remain a promising source of new medicines. The direct photoalkylation of imines offers a promising strategy for complex amines. However, the lack of efficient imine photoreactivity hinders this reaction and remains a fundamental limitation in organic photochemistry. We report an efficient photoalkylation of imines that provides primary amines directly without protecting or leaving groups. The transformation effects C-H addition across N-H imines under energy-transfer photocatalysis by a ketone. Our method is distinguished from organometallic, metal-catalyzed, and photoredox approaches to imine alkylation by its lack of protecting groups and its broad scope, which includes unactivated alkanes, protic substrates, basic amines, heterocycles, and ketone imines. We highlight this scope through the condensation and alkylation of two pharmaceutical ketones, providing complex amines succinctly. Our mechanistic analysis supports a three-step process, involving hydrogen-atom transfer to an imine triplet excited state, intersystem crossing, and radical recombination, with photocatalytic enhancement through energy transfer. We further show that N-H imines are more photoreactive than N-substituted imines, a distinction partially explained by sterics and side reactions. To fully explain this distinction, we introduce the thermodynamic parameter excited-state hydrogen-atom affinity, which is highly effective at predicting the photoreactivity of imines.
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Affiliation(s)
- Subrata K Ghosh
- The University of Houston, 4800 Calhoun Road, Houston, Texas 77004, United States
| | - Lizhe He
- The University of Houston, 4800 Calhoun Road, Houston, Texas 77004, United States
| | - Zilu Tang
- The University of Houston, 4800 Calhoun Road, Houston, Texas 77004, United States
| | - Robert J Comito
- The University of Houston, 4800 Calhoun Road, Houston, Texas 77004, United States
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4
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Urbiña-Alvarez J, Rincón-Carvajal S, Gamba-Sánchez D. Ammonia surrogates in the synthesis of primary amines. Org Biomol Chem 2023; 21:7036-7051. [PMID: 37575051 DOI: 10.1039/d3ob01202f] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Primary amines are derivatives of ammonia in which one hydrogen atom is replaced by an alkyl or aryl group. Ammonia serves as the primary nitrogen source in amination reactions, and its utilization in solution or as a pure gas has witnessed notable advancements. However, the use of gaseous ammonia remains problematic in academic laboratory settings, while employing aqueous ammonia poses challenges in highly water-sensitive transformations. Consequently, the search for alternative sources of ammonia has garnered considerable attention among the organic chemistry community. This comprehensive literature review focuses on the use of ammonia surrogates in amination reactions, irrespective of the resulting intermediate. The review emphasizes the formation of the C-N bond and underscores the importance of generating intermediate products that can be readily transformed into primary amines through well-established reactions.
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Affiliation(s)
- Julia Urbiña-Alvarez
- Laboratory of Organic Synthesis, Bio and Organocatalysis, Chemistry Department, Universidad de Los Andes, Cra 1 No. 18A-12 Q:305, Bogotá 111711, Colombia.
| | - Sergio Rincón-Carvajal
- Laboratory of Organic Synthesis, Bio and Organocatalysis, Chemistry Department, Universidad de Los Andes, Cra 1 No. 18A-12 Q:305, Bogotá 111711, Colombia.
| | - Diego Gamba-Sánchez
- Laboratory of Organic Synthesis, Bio and Organocatalysis, Chemistry Department, Universidad de Los Andes, Cra 1 No. 18A-12 Q:305, Bogotá 111711, Colombia.
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5
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Zhao X, Yu X, Liu M, Huo Y, Ji S, Li X, Chen Q. Direct Benzylic C-H Functionalization with Fluorenones under Visible-Light Irradiation. J Org Chem 2023; 88:2612-2620. [PMID: 36725672 DOI: 10.1021/acs.joc.2c02766] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
An external photocatalyst-free benzylic C-H functionalization with fluorenones under visible-light irradiation has been achieved. This transformation provides an efficient synthetic approach to 9-benzylated fluorenols in ≤91% yield with 100% atom economy under mild conditions. Spectroscopic studies suggest that a reductive quenching of photoexcited fluorenones with toluene derivatives generates ketyl radicals and benzyl radicals, which undergo a cross-coupling to afford the desired fluorenols.
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Affiliation(s)
- Xi Zhao
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Xiaofeng Yu
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Mingjun Liu
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Yanping Huo
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Shaomin Ji
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Xianwei Li
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Qian Chen
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
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6
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Yamada K, Kondo Y, Kitamura A, Kadota T, Morimoto H, Ohshima T. Organocatalytic Direct Enantioselective Hydrophosphonylation of N-Unsubstituted Ketimines for the Synthesis of α-Aminophosphonates. ACS Catal 2023. [DOI: 10.1021/acscatal.2c05953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Affiliation(s)
- Koki Yamada
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1 Higashi-ku, Fukuoka 812-8582, Japan
| | - Yuta Kondo
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1 Higashi-ku, Fukuoka 812-8582, Japan
| | - Akihiko Kitamura
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1 Higashi-ku, Fukuoka 812-8582, Japan
| | - Tetsuya Kadota
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1 Higashi-ku, Fukuoka 812-8582, Japan
| | - Hiroyuki Morimoto
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1 Higashi-ku, Fukuoka 812-8582, Japan
| | - Takashi Ohshima
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1 Higashi-ku, Fukuoka 812-8582, Japan
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7
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Shubhashish S, Wijenayake S, Huang X, Posada LF, Rubio SJB, Khanna HS, Dziengiel D, Mansour A, Suib SL. Highly Mesoporous MoO 3 Catalysts for Electrophilic Aromatic Substitution. ACS APPLIED MATERIALS & INTERFACES 2022; 14:51041-51052. [PMID: 36335644 DOI: 10.1021/acsami.2c16891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Herein, a straightforward synthesis method for highly mesoporous molybdenum oxide has been demonstrated via use of inverse micelles and molybdenum-oxo cluster formation. The synthesized catalyst is stable, crystalline, and MoO3 phase pure, as confirmed through thermogravimetric analysis, X-ray diffraction, and X-ray photoelectron spectroscopy. Further results from electron paramagnetic resonance, Raman spectroscopy, and UV-vis spectroscopy confirm the MoO3 phase purity. Chemisorption studies reveal that the synthesized material is 65 times more active than its commercial parts. The quantitative value of ammonia chemisorption for the synthesized catalyst is 1270 μmol/g, whereas the commercial catalyst only gives 22 μmol/g. These materials were tested for electrophilic substitution reactions since they are excellent solid acid. Electrophilic substitution of benzyl alcohol with toluene gives a >99% conversion with ∼80% of selectivity toward the methyl diphenylmethane product. The turnover number and turnover frequency values were calculated to be as high as 115 and 38, respectively. A substrate scope study shows that the reaction has preference toward electron-donating groups, whereas electron-withdrawing groups block the reaction. Based on the obtained results, a mechanism has been proposed.
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Affiliation(s)
- Shubhashish Shubhashish
- Department of Chemistry, University of Connecticut, U-3060, 55 North Eagleville Road, Storrs, Connecticut 06269, United States
| | - Surani Wijenayake
- Department of Chemistry, University of Connecticut, U-3060, 55 North Eagleville Road, Storrs, Connecticut 06269, United States
| | - Xueni Huang
- Department of Chemistry, University of Connecticut, U-3060, 55 North Eagleville Road, Storrs, Connecticut 06269, United States
| | - Luisa F Posada
- Department of Chemistry, University of Connecticut, U-3060, 55 North Eagleville Road, Storrs, Connecticut 06269, United States
| | - Samantha Joy B Rubio
- Department of Chemistry, University of Connecticut, U-3060, 55 North Eagleville Road, Storrs, Connecticut 06269, United States
| | - Harshul S Khanna
- Institute of Materials Science, University of Connecticut, 97 North Eagleville Road, Storrs, Connecticut 06269, United States
| | - Destiny Dziengiel
- Department of Chemistry, University of Connecticut, U-3060, 55 North Eagleville Road, Storrs, Connecticut 06269, United States
| | - Ali Mansour
- Department of Chemistry, University of Connecticut, U-3060, 55 North Eagleville Road, Storrs, Connecticut 06269, United States
| | - Steven L Suib
- Department of Chemistry, University of Connecticut, U-3060, 55 North Eagleville Road, Storrs, Connecticut 06269, United States
- Institute of Materials Science, University of Connecticut, 97 North Eagleville Road, Storrs, Connecticut 06269, United States
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8
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Kondo Y, Hirazawa Y, Kadota T, Yamada K, Morisaki K, Morimoto H, Ohshima T. One-Pot Catalytic Synthesis of α-Tetrasubstituted Amino Acid Derivatives via In Situ Generation of N-Unsubstituted Ketimines. Org Lett 2022; 24:6594-6598. [PMID: 36053018 DOI: 10.1021/acs.orglett.2c02587] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A one-pot catalytic synthesis of α-tetrasubstituted amino acid derivatives via in situ generation of N-unsubstituted ketimines is reported. Because of the irreversible formation of N-unsubstituted ketimines, the yields were higher than those generated under the conventional one-pot reaction conditions. This process prevents the need to isolate unstable N-unsubstituted ketimines with alkyl substituents and streamlines the synthesis of highly congested α-amino acid derivatives.
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Affiliation(s)
- Yuta Kondo
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| | - Yoshinobu Hirazawa
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| | - Tetsuya Kadota
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| | - Koki Yamada
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| | - Kazuhiro Morisaki
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| | - Hiroyuki Morimoto
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| | - Takashi Ohshima
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
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9
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Lee S, Shin I. Reversed-Polarity Synthesis of N-Sulfonyl Ketimines with Imidoylsilanes and Diaryliodonium Salts via Palladium-Catalyzed Reactions. J Org Chem 2022; 87:6552-6561. [PMID: 35533361 DOI: 10.1021/acs.joc.2c00116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Imines are important building blocks in organic chemistry. Iminines, aldimines and ketimines, have been traditionally synthesized by the condensation reaction of the corresponding carbonyl compound with an amine moiety. More recently, palladium-catalyzed synthesis of ketimines using imidoyl chlorides has been reported. As an alternative, we report the reversed-polarity synthesis of N-sulfonyl ketimines using an anion equivalent imidoylsilane as a new nucleophilic coupling partner in the presence of a palladium catalyst. To the best of our knowledge, this is the first report of the use of imidoylsilanes in transition-metal-catalyzed coupling reactions. Diaryliodonium salt as an electrophile, various aryl-aryl or heteroaryl-aryl N-sulfonyl ketimines were successfully prepared in up to 99% isolated yields.
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Affiliation(s)
- Seungmi Lee
- Department of Fine Chemistry, Seoul National University of Science and Technology, 232 Gongneung-ro, Nowon-gu, Seoul 01811, Korea
| | - Inji Shin
- Department of Fine Chemistry, Seoul National University of Science and Technology, 232 Gongneung-ro, Nowon-gu, Seoul 01811, Korea
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10
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Nie XK, Chen Y, Zhang SQ, Cui X, Tang Z, Li GX. Chiral Primary Amine Catalyzed Enantioselective Tandem Reactions Based on Heyns Rearrangement: Synthesis of α-Tertiary Amino Ketones. Org Lett 2022; 24:2069-2074. [PMID: 35261250 DOI: 10.1021/acs.orglett.2c00724] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Herein, we disclose a new catalytic asymmetric tandem reaction based on the Heyns rearrangement for the synthesis of chiral α-amino ketones with readily available substrates. The rearrangement is different from the Heyns rearrangement in that the α-amino ketones were obtained without the shift of the carbonyl group. The key to success is using chiral primary amine as a catalyst by mimicking glucosamine-6-phosphate synthase in catalyzing the efficient Heyns rearrangement in organisms.
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Affiliation(s)
- Xiao-Kang Nie
- Natural Products Research Center, Chengdu Institution of Biology, Chinese Academy of Science, Chengdu, Sichuan 610041, China.,University of Chinese Academy of Sciences, No. 19(A) Yuquan Road, Shijingshan District, Beijing 100049, P. R. China
| | - Yue Chen
- Natural Products Research Center, Chengdu Institution of Biology, Chinese Academy of Science, Chengdu, Sichuan 610041, China
| | - Shi-Qi Zhang
- Natural Products Research Center, Chengdu Institution of Biology, Chinese Academy of Science, Chengdu, Sichuan 610041, China
| | - Xin Cui
- Natural Products Research Center, Chengdu Institution of Biology, Chinese Academy of Science, Chengdu, Sichuan 610041, China
| | - Zhuo Tang
- Natural Products Research Center, Chengdu Institution of Biology, Chinese Academy of Science, Chengdu, Sichuan 610041, China
| | - Guang-Xun Li
- Natural Products Research Center, Chengdu Institution of Biology, Chinese Academy of Science, Chengdu, Sichuan 610041, China
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11
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Morimoto H. Development of Greener Catalytic Synthetic Methods of Nitrogen-Containing Compounds Using <i>N</i>-Unprotected Ketimines. J SYN ORG CHEM JPN 2022. [DOI: 10.5059/yukigoseikyokaishi.80.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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12
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Kadota T, Sawa M, Kondo Y, Morimoto H, Ohshima T. Catalytic Enantioselective Strecker Reaction of Isatin-Derived N-Unsubstituted Ketimines. Org Lett 2021; 23:4553-4558. [PMID: 34029103 DOI: 10.1021/acs.orglett.1c01194] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A catalytic enantioselective Strecker reaction of isatin-derived N-unsubstituted ketimines directly afforded the N-unprotected α-aminonitriles with a tetrasubstituted carbon stereocenter in up to 99% ee without requiring protection/deprotection steps. One-pot Strecker reactions from the parent carbonyl compounds were also realized with comparable yields and enantioselectivities. Direct transformations of the N-unprotected α-aminonitrile products streamlined the synthesis of unnatural amino acid derivatives and achieved the shortest one-pot stereoselective routes to a biologically active compound reported to date.
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Affiliation(s)
- Tetsuya Kadota
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1 Higashi-ku, Fukuoka 812-8582, Japan
| | - Masanao Sawa
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1 Higashi-ku, Fukuoka 812-8582, Japan
| | - Yuta Kondo
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1 Higashi-ku, Fukuoka 812-8582, Japan
| | - Hiroyuki Morimoto
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1 Higashi-ku, Fukuoka 812-8582, Japan
| | - Takashi Ohshima
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1 Higashi-ku, Fukuoka 812-8582, Japan
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13
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Kent GT, Cook AW, Damon PL, Lewis RA, Wu G, Hayton TW. Synthesis and Characterization of Two "Tied-Back" Lithium Ketimides and Isolation of a Ketimide-Bridged [Cr 2] 6+ Dimer with Strong Antiferromagnetic Coupling. Inorg Chem 2021; 60:4996-5004. [PMID: 33764048 DOI: 10.1021/acs.inorgchem.1c00052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Reaction of 1 equiv of KN(SiMe3)2 with 9-fluorenone results in the formation of (Me3Si)N═C13H8 (1) in high yield after work-up. Addition of 1 equiv of phenol to 1 results in rapid desilylation and formation of 9-fluorenone imine, HN═C13H8 (2). Subsequent reaction of 2 with 1 equiv of LiNiPr2 results in deprotonation and formation of [Li(Et2O)]4[N═C13H8]4 (3) in good yield. Reaction of 1 equiv of KN(SiMe3)2 with 2-adamantanone for 7 days at room temperature results in the formation of (Me3Si)N═C10H14 (4) in good yield. Dissolution of 4 in neat MeOH results in rapid desilylation concomitant with formation of 2-adamantanone imine, HN═C10H14 (5). Subsequent reaction of 5 with 1 equiv of LiNiPr2 results in formation of [Li(THF)]4[N═C10H14]4 (6). Both 3 and 6 were characterized by X-ray crystallography. Finally, reaction of CrCl3 with 3.5 equiv of 6 results in formation of the [Cr2]6+ dimer, [Li][Cr2(N═C10H14)7] (7), which can be isolated in modest yield after work-up. Complex 7 features a Cr-Cr bond length of 2.653(2) Å. Additionally, solid-state magnetic susceptibility measurements reveal strong antiferromagnetic coupling between the two Cr centers, with J = -200 cm-1.
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Affiliation(s)
- Greggory T Kent
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, California 93106, United States
| | - Andrew W Cook
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, California 93106, United States
| | - Peter L Damon
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, California 93106, United States
| | - Richard A Lewis
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, California 93106, United States
| | - Guang Wu
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, California 93106, United States
| | - Trevor W Hayton
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, California 93106, United States
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14
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Shibata S, Masui Y, Onaka M. Efficient solvent-free synthesis of N-unsubstituted ketimines from ketones and ammonia on porous solid acids. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.152840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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15
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Shibasaki K, Togo H. Novel transformation of aryl 2-iodophenyl ketones into 1,3-diarylisoquinolines with (TMS)2NH, styrenes, NIS, and BuOK. Tetrahedron 2021. [DOI: 10.1016/j.tet.2020.131864] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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16
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Uchikura T, Suzuki R, Suda Y, Akiyama T. Enantioselective Synthesis of 2‐Substituted Indoles Bearing Trifluoromethyl Moiety by the Friedel‐Crafts Alkylation Reaction of 4,7‐Dihydroindole with
N
−H Trifluoromethyl Ketimines. ChemCatChem 2020. [DOI: 10.1002/cctc.202000920] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Tatsuhiro Uchikura
- Department of Chemistry Gakushuin University 1-5-1 Mejiro Toshima-ku, Tokyo Japan
| | - Riku Suzuki
- Department of Chemistry Gakushuin University 1-5-1 Mejiro Toshima-ku, Tokyo Japan
| | - Yusuke Suda
- Department of Chemistry Gakushuin University 1-5-1 Mejiro Toshima-ku, Tokyo Japan
| | - Takahiko Akiyama
- Department of Chemistry Gakushuin University 1-5-1 Mejiro Toshima-ku, Tokyo Japan
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17
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Morisaki K, Morimoto H, Ohshima T. Recent Progress on Catalytic Addition Reactions to N-Unsubstituted Imines. ACS Catal 2020. [DOI: 10.1021/acscatal.0c01212] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Kazuhiro Morisaki
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Hiroyuki Morimoto
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Takashi Ohshima
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
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18
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Kondo Y, Morimoto H, Ohshima T. Recent Progress towards the Use of Benzophenone Imines as an Ammonia Equivalent. CHEM LETT 2020. [DOI: 10.1246/cl.200099] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Yuta Kondo
- Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Hiroyuki Morimoto
- Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Takashi Ohshima
- Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
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19
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Yonesaki R, Kusagawa I, Morimoto H, Hayashi T, Ohshima T. Rhodium(I)/Chiral Diene‐Catalyzed Enantioselective Addition of Boronic Acids to
N
‐Unsubstituted Isatin‐Derived Ketimines. Chem Asian J 2020; 15:499-502. [DOI: 10.1002/asia.201901745] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Indexed: 12/14/2022]
Affiliation(s)
- Ryohei Yonesaki
- Graduate School of Pharmaceutical SciencesKyushu University Maidashi 3-1-1 Higashi-ku Fukuoka 812-8582 Japan
| | - Ibuki Kusagawa
- Graduate School of Pharmaceutical SciencesKyushu University Maidashi 3-1-1 Higashi-ku Fukuoka 812-8582 Japan
| | - Hiroyuki Morimoto
- Graduate School of Pharmaceutical SciencesKyushu University Maidashi 3-1-1 Higashi-ku Fukuoka 812-8582 Japan
| | - Tamio Hayashi
- Division of Chemistry and Biological ChemistrySchool of Physical and Mathematical SciencesNanyang Technological University 21 Nanyang Link Singapore 637371 Singapore
| | - Takashi Ohshima
- Graduate School of Pharmaceutical SciencesKyushu University Maidashi 3-1-1 Higashi-ku Fukuoka 812-8582 Japan
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