101
|
Xiao Y, Wang N, Wan LX, Zhou XL, Li X, Gao F. Iron-Catalyzed Skeletal Conversion of Lathyrane to Premyrsinane Euphorbia Diterpenes and Their Cytotoxic Activities. JOURNAL OF NATURAL PRODUCTS 2021; 84:1838-1842. [PMID: 34018743 DOI: 10.1021/acs.jnatprod.0c01363] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Two new premyrsinane-type diterpenes (2 and 3) as diastereomers were synthesized from lathyrane-type diterpene euphorbia factor L3 (1) for the first time via an efficient Fe(acac)3-catalyzed skeleton conversion process. This conversion features a biogenetically inspired strategy that relies on a concise reductive olefin coupling involving intramolecular Michael addition with free radicals. The structures of 2 and 3 were elucidated by a combination of the interpretation of their spectroscopic data and single-crystal X-ray diffraction analysis. The premyrsinane diterpenes 2 and 3 exhibited cytotoxic activity against the 4T1 breast cancer cell line, while the parent compound euphorbia factor L3 (1) was inactive. The current results not only confirmed the biogenetic relationship between lathyranes and premyrsinanes for the first time but also suggested a novel method for the preparation of naturally rare premyrsinane diterpenes with high bioactivity from the more abundant natural lathyrane diterpenes.
Collapse
Affiliation(s)
- Yao Xiao
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, People's Republic of China
| | - Neng Wang
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, People's Republic of China
| | - Lin-Xi Wan
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, People's Republic of China
| | - Xian-Li Zhou
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, People's Republic of China
| | - Xiaohuan Li
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, People's Republic of China
| | - Feng Gao
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, People's Republic of China
| |
Collapse
|
102
|
Radical philicity and its role in selective organic transformations. Nat Rev Chem 2021; 5:486-499. [PMID: 37118440 DOI: 10.1038/s41570-021-00284-3] [Citation(s) in RCA: 140] [Impact Index Per Article: 46.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/21/2021] [Indexed: 12/11/2022]
Abstract
Radical intermediates in organic chemistry lack a full octet of electrons and, thus, are commonly said to be electron deficient. By denotation, such a statement is technically correct; however, in modern literature, the term 'electron deficient' carries a connotation of electrophilicity. This lexical quirk leads one to predict that all radicals should behave as electrophiles, when this is not the case. Indeed, practitioners of radical chemistry have known for decades that many radicals behave as nucleophiles, sometimes strongly so. This Review aims to establish guidelines for understanding radical philicity by highlighting examples from recent literature as a demonstration of general reactivity paradigms across a series of different carbon-based and heteroatom-based radicals. We present strategies for predicting the philicity of a given radical on the basis of qualitative features of the radical's structure. Finally, we discuss the implications of radical philicity to selective hydrogen atom transfer.
Collapse
|
103
|
Xin Z, Wang H, He H, Zhao X, Gao S. Asymmetric Total Synthesis of Norzoanthamine. Angew Chem Int Ed Engl 2021; 60:12807-12812. [PMID: 33822444 DOI: 10.1002/anie.202102643] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 03/26/2021] [Indexed: 11/08/2022]
Abstract
We report herein the asymmetric total synthesis of norzoanthamine using radical reactions as key steps for rapid access to the congested carbocyclic core, which is the major synthetic challenge for most zoanthamine alkaloids. (1) The Ueno-Stork radical cyclization was applied to construct the adjacent quaternary centers at the C-9 and C-22 positions; (2) a Co-catalyzed HAT radical reaction was successfully applied to construct the quaternary center at C-12 via Csp3 -Csp2 bond formation; (3) a Mn-catalyzed HAT radical reaction was used to stereospecifically reduce the tetra-substituted olefin (C13=C18) and install the contiguous stereocenters in proximity to the quaternary center. A one-pot bio-inspired cyclization step was finally applied to forge the unstable bis-amino acetal skeleton. Our approach can precisely control the stereochemistry of seven vicinal stereocenters and effectively construct the highly congested heptacyclic skeleton.
Collapse
Affiliation(s)
- Zhengyuan Xin
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes, School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China
| | - Hui Wang
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes, School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China
| | - Haibing He
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China
| | - Xiaoli Zhao
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes, School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China
| | - Shuanhu Gao
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes, School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China.,Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China
| |
Collapse
|
104
|
Xin Z, Wang H, He H, Zhao X, Gao S. Asymmetric Total Synthesis of Norzoanthamine. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202102643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Zhengyuan Xin
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes School of Chemistry and Molecular Engineering East China Normal University 3663 North Zhongshan Road Shanghai 200062 China
| | - Hui Wang
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes School of Chemistry and Molecular Engineering East China Normal University 3663 North Zhongshan Road Shanghai 200062 China
| | - Haibing He
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development East China Normal University 3663 North Zhongshan Road Shanghai 200062 China
| | - Xiaoli Zhao
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes School of Chemistry and Molecular Engineering East China Normal University 3663 North Zhongshan Road Shanghai 200062 China
| | - Shuanhu Gao
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes School of Chemistry and Molecular Engineering East China Normal University 3663 North Zhongshan Road Shanghai 200062 China
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development East China Normal University 3663 North Zhongshan Road Shanghai 200062 China
| |
Collapse
|
105
|
Puls F, Linke P, Kataeva O, Knölker HJ. Iron-Catalyzed Wacker-type Oxidation of Olefins at Room Temperature with 1,3-Diketones or Neocuproine as Ligands*. Angew Chem Int Ed Engl 2021; 60:14083-14090. [PMID: 33856090 PMCID: PMC8251641 DOI: 10.1002/anie.202103222] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Indexed: 11/11/2022]
Abstract
Herein, we describe a convenient and general method for the oxidation of olefins to ketones using either tris(dibenzoylmethanato)iron(III) [Fe(dbm)3 ] or a combination of iron(II) chloride and neocuproine (2,9-dimethyl-1,10-phenanthroline) as catalysts and phenylsilane (PhSiH3 ) as additive. All reactions proceed efficiently at room temperature using air as sole oxidant. This transformation has been applied to a variety of substrates, is operationally simple, proceeds under mild reaction conditions, and shows a high functional-group tolerance. The ketones are formed smoothly in up to 97 % yield and with 100 % regioselectivity, while the corresponding alcohols were observed as by-products. Labeling experiments showed that an incorporated hydrogen atom originates from the phenylsilane. The oxygen atom of the ketone as well as of the alcohol derives from the ambient atmosphere.
Collapse
Affiliation(s)
- Florian Puls
- Fakultät Chemie und Lebensmittelchemie, Technische Universität Dresden, Bergstrasse 66, 01069, Dresden, Germany
| | - Philipp Linke
- Fakultät Chemie und Lebensmittelchemie, Technische Universität Dresden, Bergstrasse 66, 01069, Dresden, Germany
| | - Olga Kataeva
- A. E. Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Arbuzov Str. 8, Kazan, 420088, Russia
| | - Hans-Joachim Knölker
- Fakultät Chemie und Lebensmittelchemie, Technische Universität Dresden, Bergstrasse 66, 01069, Dresden, Germany
| |
Collapse
|
106
|
Puls F, Linke P, Kataeva O, Knölker H. Iron‐Catalyzed Wacker‐type Oxidation of Olefins at Room Temperature with 1,3‐Diketones or Neocuproine as Ligands**. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103222] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Florian Puls
- Fakultät Chemie und Lebensmittelchemie Technische Universität Dresden Bergstrasse 66 01069 Dresden Germany
| | - Philipp Linke
- Fakultät Chemie und Lebensmittelchemie Technische Universität Dresden Bergstrasse 66 01069 Dresden Germany
| | - Olga Kataeva
- A. E. Arbuzov Institute of Organic and Physical Chemistry FRC Kazan Scientific Center Russian Academy of Sciences Arbuzov Str. 8 Kazan 420088 Russia
| | - Hans‐Joachim Knölker
- Fakultät Chemie und Lebensmittelchemie Technische Universität Dresden Bergstrasse 66 01069 Dresden Germany
| |
Collapse
|
107
|
Yin YN, Ding RQ, Ouyang DC, Zhang Q, Zhu R. Highly chemoselective synthesis of hindered amides via cobalt-catalyzed intermolecular oxidative hydroamidation. Nat Commun 2021; 12:2552. [PMID: 33953181 PMCID: PMC8100129 DOI: 10.1038/s41467-021-22373-z] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 03/05/2021] [Indexed: 12/05/2022] Open
Abstract
α-Tertiary amides are of great importance for medicinal chemistry. However, they are often challenging to access through conventional methods due to reactivity and chemoselectivity issues. Here, we report a single-step approach towards such amides via cobalt-catalyzed intermolecular oxidative hydroamidation of unactivated alkenes, using nitriles of either solvent- or reagent-quantities. This protocol is selective for terminal alkenes over groups that rapidly react under known carbocation amidation conditions such as tertiary alcohols, electron-rich alkenes, ketals, weak C−H bonds, and carboxylic acids. Straightforward access to a diverse array of hindered amides is demonstrated, including a rapid synthesis of an aminoadamantane-derived pharmaceutical intermediate. α-Tertiary amides are common in bioactive natural products and pharmaceuticals, but challenging to access by conventional methods. Here, the authors report a single-step approach toward α-tertiary amides via cobalt-catalyzed intermolecular oxidative hydroamidation of unactivated alkenes.
Collapse
Affiliation(s)
- Yun-Nian Yin
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Rui-Qi Ding
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Dong-Chen Ouyang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Qing Zhang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Rong Zhu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing, China.
| |
Collapse
|
108
|
Recent advances in the total synthesis of natural products bearing the contiguous all-carbon quaternary stereocenters. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.153029] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
109
|
Abstract
Minisci-type reactions have been widely known as reactions that involve the addition
of carbon-centered radicals to basic heteroarenes followed by formal hydrogen atom loss.
While the originally developed protocols for radical generation remain in active use today, in
recent years, the new array of radical generation strategies have allowed the use of a wider
variety of radical precursors that often operate under milder and more benign conditions. New
transformations based on free radical reactivity are now available to a synthetic chemist, to
utilize a Minisci-type reaction. Radical-generation methods based on photoredox catalysis
and electrochemistry, which utilize thermal cleavage or the in situ generation of reactive radical
precursors, have become popular approaches. Our review will cover the remarkable literature
that has been reported on this topic in recent 5 years, from 2015-01 to 2020-01, in an
attempt to provide guidance to the synthetic chemist on both the challenges that need to be overcome and the applications
in organic synthesis.
Collapse
Affiliation(s)
- Wengui Wang
- Shandong Provincial Key Laboratory of Fluorine Chemistry and Chemical Materials, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, China
| | - Shoufeng Wang
- Shandong Provincial Key Laboratory of Fluorine Chemistry and Chemical Materials, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, China
| |
Collapse
|
110
|
|
111
|
Yang Z, Niu Y, He X, Chen S, Liu S, Li Z, Chen X, Zhang Y, Lan Y, Shen X. Tuning the reactivity of alkoxyl radicals from 1,5-hydrogen atom transfer to 1,2-silyl transfer. Nat Commun 2021; 12:2131. [PMID: 33837201 PMCID: PMC8035221 DOI: 10.1038/s41467-021-22382-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 03/04/2021] [Indexed: 01/10/2023] Open
Abstract
Controlling the reactivity of reactive intermediates is essential to achieve selective transformations. Due to the facile 1,5-hydrogen atom transfer (HAT), alkoxyl radicals have been proven to be important synthetic intermediates for the δ-functionalization of alcohols. Herein, we disclose a strategy to inhibit 1,5-HAT by introducing a silyl group into the α-position of alkoxyl radicals. The efficient radical 1,2-silyl transfer (SiT) allows us to make various α-functionalized products from alcohol substrates. Compared with the direct generation of α-carbon radicals from oxidation of α-C-H bond of alcohols, the 1,2-SiT strategy distinguishes itself by the generation of alkoxyl radicals, the tolerance of many functional groups, such as intramolecular hydroxyl groups and C-H bonds next to oxygen atoms, and the use of silyl alcohols as limiting reagents.
Collapse
Affiliation(s)
- Zhaoliang Yang
- The Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds and Materials, Ministry of Education, Wuhan University, Wuhan, People's Republic of China
| | - Yunhong Niu
- The Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds and Materials, Ministry of Education, Wuhan University, Wuhan, People's Republic of China
| | - Xiaoqian He
- School of Chemistry and Chemical Engineering, Chongqing Key Laboratory of Theoretical and Computational Chemistry, Chongqing University, Chongqing, People's Republic of China
| | - Suo Chen
- The Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds and Materials, Ministry of Education, Wuhan University, Wuhan, People's Republic of China
| | - Shanshan Liu
- The Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds and Materials, Ministry of Education, Wuhan University, Wuhan, People's Republic of China
| | - Zhengyu Li
- The Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds and Materials, Ministry of Education, Wuhan University, Wuhan, People's Republic of China
| | - Xiang Chen
- The Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds and Materials, Ministry of Education, Wuhan University, Wuhan, People's Republic of China
| | - Yunxiao Zhang
- The Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds and Materials, Ministry of Education, Wuhan University, Wuhan, People's Republic of China
| | - Yu Lan
- School of Chemistry and Chemical Engineering, Chongqing Key Laboratory of Theoretical and Computational Chemistry, Chongqing University, Chongqing, People's Republic of China.
- College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou, People's Republic of China.
| | - Xiao Shen
- The Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds and Materials, Ministry of Education, Wuhan University, Wuhan, People's Republic of China.
| |
Collapse
|
112
|
Zhang B, He J, Li Y, Song T, Fang Y, Li C. Cobalt-Catalyzed Markovnikov-Selective Radical Hydroacylation of Unactivated Alkenes with Acylphosphonates. J Am Chem Soc 2021; 143:4955-4961. [PMID: 33783191 DOI: 10.1021/jacs.1c02629] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Acylphosphonates having the 5,5-dimethyl-1,3,2-dioxophosphinanyl skeleton are developed as efficient intermolecular radical acylation reagents, which enable the cobalt-catalyzed Markovnikov hydroacylation of unactivated alkenes at room temperature under mild conditions. The protocol exhibits broad substrate scope and wide functional group compatibility, providing branched ketones in satisfactory yields. A mechanism involving the Co-H mediated hydrogen atom transfer and subsequent trapping of alkyl radicals by acylphosphonates is proposed.
Collapse
Affiliation(s)
- Benxiang Zhang
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Jiayan He
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Yi Li
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Tao Song
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Yewen Fang
- School of Materials and Chemical Engineering, Ningbo University of Technology, No. 201 Fenghua Road, Ningbo 315211, China
| | - Chaozhong Li
- School of Materials and Chemical Engineering, Ningbo University of Technology, No. 201 Fenghua Road, Ningbo 315211, China.,Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| |
Collapse
|
113
|
Abstract
AbstractHydrogen atom transfer (HAT) is one of the fundamental transformations of organic chemistry, allowing the interconversion of open- and closed-shell species through the concerted movement of a proton and an electron. Although the value of this transformation is well appreciated in isolation, with it being used for homolytic C–H activation via abstractive HAT and radical reduction via donative HAT, cooperative HAT (cHAT) reactions, in which two hydrogen atoms are removed or donated to vicinal reaction centers in succession through radical intermediates, are comparatively unknown outside of the mechanism of desaturase enzymes. This tandem reaction scheme has important ramifications in the thermochemistry of each HAT, with the bond dissociation energy (BDE) of the C–H bond adjacent to the radical center being significantly lowered relative to that of the parent alkane, allowing each HAT to be performed by different species. Herein, we discuss the thermodynamic basis of this bond strength differential in cHAT and demonstrate its use as a design principle in organic chemistry for both dehydrogenative (application 1) and hydrogenative (application 2) reactions. We hope that this overview will highlight the exciting reactivity that is possible with cHAT and inspire further developments with this mechanistic approach.1 Introduction and Theory2 Application: Dehydrogenative Transformations3 Application: Alkene Hydrogenation4 Future Applications of cHAT
Collapse
|
114
|
Sasaki M, Iwasaki K, Arai K. Synthesis and Structural Implication of the JKLMN-Ring Fragment of Caribbean Ciguatoxin C-CTX-1. J Org Chem 2021; 86:4580-4597. [PMID: 33667088 DOI: 10.1021/acs.joc.0c03031] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Synthesis of the JKLMN-ring fragment of Caribbean ciguatoxin C-CTX-1, the causative toxin of ciguatera fish poisoning in the Caribbean Sea and the Northeast Atlantic areas, is described in detail. Key to the synthesis are a [2,3]-sigmatropic rearrangement to construct a seven-membered α-hydroxy exo-enol ether, stereoselective construction of an angular tetrasubstituted stereogenic center on the seven-membered M-ring by a hydrogen atom transfer-based reductive olefin coupling, Suzuki-Miyaura coupling of the KLMN-ring enol phosphate with a highly congested M-ring, and silica gel-mediated epoxide ring opening to form the J-ring. Comparison of the nuclear magnetic resonance spectroscopic data for the synthesized fragment with those for the natural product provided support for the formerly assigned structure of the N-ring in the right-hand terminal of C-CTX-1.
Collapse
Affiliation(s)
- Makoto Sasaki
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Japan
| | - Kotaro Iwasaki
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Japan
| | - Keisuke Arai
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Japan
| |
Collapse
|
115
|
Parida SK, Hota SK, Kumar R, Murarka S. Late‐Stage Alkylation of Heterocycles Using
N
‐(Acyloxy)phthalimides. Chem Asian J 2021; 16:879-889. [DOI: 10.1002/asia.202100151] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/03/2021] [Indexed: 11/06/2022]
Affiliation(s)
- Sushanta Kumar Parida
- Department of Chemistry Indian Institute of Technology Jodhpur Karwar 342037 Rajasthan India
| | - Sudhir Kumar Hota
- Department of Chemistry Indian Institute of Technology Jodhpur Karwar 342037 Rajasthan India
| | - Raushan Kumar
- Department of Chemistry Indian Institute of Technology Jodhpur Karwar 342037 Rajasthan India
| | - Sandip Murarka
- Department of Chemistry Indian Institute of Technology Jodhpur Karwar 342037 Rajasthan India
| |
Collapse
|
116
|
Chen P, Wang C, Yang R, Xu H, Wu J, Jiang H, Chen K, Ma Z. Asymmetric Total Synthesis of Dankasterones A and B and Periconiastone A Through Radical Cyclization. Angew Chem Int Ed Engl 2021; 60:5512-5518. [PMID: 33206427 DOI: 10.1002/anie.202013881] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Indexed: 12/11/2022]
Abstract
We describe herein the assembly of the cis-decalin framework through radical cyclization initiated by metal-catalyzed hydrogen atom transfer (MHAT), further applied it in the asymmetric synthesis of dankasterones A and B and periconiastone A. Position-selective C-H oxygenation allowed for installation of the necessary functionality. A radical rearrangement was adopted to create 13(14→8)abeo-8-ergostane skeleton. Interconversion of dankasterone B and periconiastone A was realized through biomimetic intramolecular aldol and retro-aldol reactions. The MHAT-based approach, serves as a new dissection means, is complementary to the conventional ways to establish cis-decalin framework.
Collapse
Affiliation(s)
- Pengquan Chen
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry & Chemical Engineering, South China University of Technology, Wushan Road-381, Guangzhou, 510641, China
| | - Cheng Wang
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry & Chemical Engineering, South China University of Technology, Wushan Road-381, Guangzhou, 510641, China
| | - Rui Yang
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry & Chemical Engineering, South China University of Technology, Wushan Road-381, Guangzhou, 510641, China
| | - Hongjin Xu
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry & Chemical Engineering, South China University of Technology, Wushan Road-381, Guangzhou, 510641, China
| | - Jinghua Wu
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry & Chemical Engineering, South China University of Technology, Wushan Road-381, Guangzhou, 510641, China
| | - Huanfeng Jiang
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry & Chemical Engineering, South China University of Technology, Wushan Road-381, Guangzhou, 510641, China
| | - Kai Chen
- College of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, China.,Lab of Computational Chemistry and Drug Design, State Key Laboratory of Chemical Oncogenomics, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Zhiqiang Ma
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry & Chemical Engineering, South China University of Technology, Wushan Road-381, Guangzhou, 510641, China
| |
Collapse
|
117
|
Vrubliauskas D, Gross BM, Vanderwal CD. Stereocontrolled Radical Bicyclizations of Oxygenated Precursors Enable Short Syntheses of Oxidized Abietane Diterpenoids. J Am Chem Soc 2021; 143:2944-2952. [PMID: 33555176 DOI: 10.1021/jacs.0c13300] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The power of cation-initiated cyclizations of polyenes for the synthesis of polycyclic terpenoids cannot be overstated. However, a major limitation is the intolerance of many relevant reaction conditions toward the inclusion in the substrate of polar functionality, particularly in unprotected form. Radical polycyclizations are important alternatives to bioinspired cationic variants, in part owing to the range of possible initiation strategies, and in part for the functional group tolerance of radical reactions. In this article, we demonstrate that Co-catalyzed MHAT-initiated radical bicyclizations are not only tolerant of oxidation at virtually every position in the substrate, oftentimes in unprotected form, but these functional groups can also contribute to high levels of stereochemical control in these complexity-generating transformations. Specifically, we show the effects of protected or unprotected hydroxy groups at six different positions and their impact on stereoselectivity. Further, we show how multiply oxidized substrates perform in these reactions, and finally, we document the utility of these reactions in the synthesis of three aromatic abietane diterpenoids.
Collapse
Affiliation(s)
- Darius Vrubliauskas
- 1102 Natural Sciences II, Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Benjamin M Gross
- 1102 Natural Sciences II, Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Christopher D Vanderwal
- 1102 Natural Sciences II, Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| |
Collapse
|
118
|
Kamei Y, Seino Y, Yamaguchi Y, Yoshino T, Maeda S, Kojima M, Matsunaga S. Silane- and peroxide-free hydrogen atom transfer hydrogenation using ascorbic acid and cobalt-photoredox dual catalysis. Nat Commun 2021; 12:966. [PMID: 33574227 PMCID: PMC7878493 DOI: 10.1038/s41467-020-20872-z] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 12/16/2020] [Indexed: 11/09/2022] Open
Abstract
Hydrogen atom transfer (HAT) hydrogenation has recently emerged as an indispensable method for the chemoselective reduction of unactivated alkenes. However, the hitherto reported systems basically require stoichiometric amounts of silanes and peroxides, which prevents wider applications, especially with respect to sustainability and safety concerns. Herein, we report a silane- and peroxide-free HAT hydrogenation using a combined cobalt/photoredox catalysis and ascorbic acid (vitamin C) as a sole stoichiometric reactant. A cobalt salophen complex is identified as the optimal cocatalyst for this environmentally benign HAT hydrogenation in aqueous media, which exhibits high functional-group tolerance. In addition to its applicability in the late-stage hydrogenation of amino-acid derivatives and drug molecules, this method offers unique advantage in direct transformation of unprotected sugar derivatives and allows the HAT hydrogenation of unprotected C-glycoside in higher yield compared to previously reported HAT hydrogenation protocols. The proposed mechanism is supported by experimental and theoretical studies.
Collapse
Affiliation(s)
- Yuji Kamei
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, 060-0812, Japan
| | - Yusuke Seino
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, 060-0812, Japan
| | - Yuto Yamaguchi
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, 060-0812, Japan
| | - Tatsuhiko Yoshino
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, 060-0812, Japan
| | - Satoshi Maeda
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo, 001-0021, Japan
- Faculty of Science, Hokkaido University, Sapporo, 060-0810, Japan
- JST, ERATO Maeda Artificial Intelligence for Chemical Reaction Design and Discovery Project, Sapporo, 060-0810, Japan
| | - Masahiro Kojima
- Faculty of Pharmaceutical Sciences, 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.
| |
Collapse
|
119
|
Nambo M, Tahara Y, Yim JCH, Yokogawa D, Crudden CM. Synthesis of quaternary centres by single electron reduction and alkylation of alkylsulfones. Chem Sci 2021; 12:4866-4871. [PMID: 34168761 PMCID: PMC8179647 DOI: 10.1039/d1sc00133g] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
A new method for the generation of tertiary radicals through single electron reduction of alkylsulfones promoted by Zn and 1,10-phenanthroline has been developed. These radicals could be employed in the Giese reaction, affording structurally diverse quaternary products in good yields. With the high modularity and functional group compatibility of sulfones, the utility of this method was demonstrated by intramolecular and iterative reactions to give complex structures. The radical generation process was investigated by control experiments and theoretical calculations. A new method for the generation of tertiary radicals through single electron reduction of alkylsulfones promoted by Zn and 1,10-phenanthroline has been developed.![]()
Collapse
Affiliation(s)
- Masakazu Nambo
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University Chikusa Nagoya Aichi 464-8601 Japan
| | - Yasuyo Tahara
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University Chikusa Nagoya Aichi 464-8601 Japan
| | - Jacky C-H Yim
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University Chikusa Nagoya Aichi 464-8601 Japan
| | - Daisuke Yokogawa
- Graduate School of Arts and Science, The University of Tokyo Komaba, Meguro-ku Tokyo 153-8902 Japan
| | - Cathleen M Crudden
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University Chikusa Nagoya Aichi 464-8601 Japan .,Department of Chemistry, Queen's University Chernoff Hall Kingston Ontario K7L 3N6 Canada
| |
Collapse
|
120
|
Pitre SP, Allred TK, Overman LE. Lewis Acid Activation of Fragment-Coupling Reactions of Tertiary Carbon Radicals Promoted by Visible-Light Irradiation of EDA Complexes. Org Lett 2021; 23:1103-1106. [PMID: 33492152 DOI: 10.1021/acs.orglett.1c00023] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The addition of tertiary carbon radicals generated from N-(acyloxy)phthalimide esters to cyclic α,β-unsaturated ketones and lactones is markedly enhanced by the addition of substoichiometric amounts of a Ln(OTf)3. The reaction is accomplished by irradiation with visible light in the absence of a photosensitizer and is suggested to proceed by excitation of a ternary electron donor-acceptor complex between the NHPI ester, Hantzsch ester, and a Ln(OTf)3.
Collapse
Affiliation(s)
- Spencer P Pitre
- Department of Chemistry, Oklahoma State University, 107 Physical Sciences, Stillwater, Oklahoma 74078, United States
| | - Tyler K Allred
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Larry E Overman
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| |
Collapse
|
121
|
Chen P, Wang C, Yang R, Xu H, Wu J, Jiang H, Chen K, Ma Z. Asymmetric Total Synthesis of Dankasterones A and B and Periconiastone A Through Radical Cyclization. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202013881] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Pengquan Chen
- Key Lab of Functional Molecular Engineering of Guangdong Province School of Chemistry & Chemical Engineering South China University of Technology Wushan Road-381 Guangzhou 510641 China
| | - Cheng Wang
- Key Lab of Functional Molecular Engineering of Guangdong Province School of Chemistry & Chemical Engineering South China University of Technology Wushan Road-381 Guangzhou 510641 China
| | - Rui Yang
- Key Lab of Functional Molecular Engineering of Guangdong Province School of Chemistry & Chemical Engineering South China University of Technology Wushan Road-381 Guangzhou 510641 China
| | - Hongjin Xu
- Key Lab of Functional Molecular Engineering of Guangdong Province School of Chemistry & Chemical Engineering South China University of Technology Wushan Road-381 Guangzhou 510641 China
| | - Jinghua Wu
- Key Lab of Functional Molecular Engineering of Guangdong Province School of Chemistry & Chemical Engineering South China University of Technology Wushan Road-381 Guangzhou 510641 China
| | - Huanfeng Jiang
- Key Lab of Functional Molecular Engineering of Guangdong Province School of Chemistry & Chemical Engineering South China University of Technology Wushan Road-381 Guangzhou 510641 China
| | - Kai Chen
- College of Chemistry and Chemical Engineering Central South University Changsha 410083 China
- Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen 518055 China
| | - Zhiqiang Ma
- Key Lab of Functional Molecular Engineering of Guangdong Province School of Chemistry & Chemical Engineering South China University of Technology Wushan Road-381 Guangzhou 510641 China
| |
Collapse
|
122
|
Ohuchi S, Koyama H, Shigehisa H. Catalytic Synthesis of Cyclic Guanidines via Hydrogen Atom Transfer and Radical-Polar Crossover. ACS Catal 2021. [DOI: 10.1021/acscatal.0c05359] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Shunya Ohuchi
- Faculty of Pharmacy, Musashino University, 1-1-20 Shinmachi, Nishitokyo-shi, Tokyo 202-8585, Japan
| | - Hiroki Koyama
- Faculty of Pharmacy, Musashino University, 1-1-20 Shinmachi, Nishitokyo-shi, Tokyo 202-8585, Japan
| | - Hiroki Shigehisa
- Faculty of Pharmacy, Musashino University, 1-1-20 Shinmachi, Nishitokyo-shi, Tokyo 202-8585, Japan
| |
Collapse
|
123
|
Senapati BK. Recent progress in the synthesis of the furanosteroid family of natural products. Org Chem Front 2021. [DOI: 10.1039/d0qo01454k] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This review focuses on an overview of recent advances in the synthesis of furanosteroids and illustrates their applications in medicinal chemistry over the period of 2005–present.
Collapse
|
124
|
Fang T, Qiu J, Yang K, Song Q. Photo-induced weak base-catalyzed synthesis of α-haloboronates from vinylboronates and polyfluoroalkyl halides. Org Chem Front 2021. [DOI: 10.1039/d1qo00169h] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
An unprecedented strategy for the synthesis of sp2-α-haloboronates has been developed. Unique KOAc catalytic system, high synthetic application value of the product and no participation of metal constitute the notable features of this reaction.
Collapse
Affiliation(s)
- Tongchang Fang
- Key Laboratory of Molecule Synthesis and Function Discovery
- Fujian Province University
- College of Chemistry at Fuzhou University Fuzhou
- Fujian
- China
| | - Jian Qiu
- Key Laboratory of Molecule Synthesis and Function Discovery
- Fujian Province University
- College of Chemistry at Fuzhou University Fuzhou
- Fujian
- China
| | - Kai Yang
- Key Laboratory of Molecule Synthesis and Function Discovery
- Fujian Province University
- College of Chemistry at Fuzhou University Fuzhou
- Fujian
- China
| | - Qiuling Song
- Key Laboratory of Molecule Synthesis and Function Discovery
- Fujian Province University
- College of Chemistry at Fuzhou University Fuzhou
- Fujian
- China
| |
Collapse
|
125
|
Xie Y, Huang W, Qin S, Fu S, Liu B. Catalytic radical cascade cyclization of alkene-tethered enones to fused bicyclic cyclopropanols. Org Chem Front 2021. [DOI: 10.1039/d1qo01312b] [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
Fused bicyclic cyclopropanols were achieved via an unprecedented HAT-triggered radical cascade reaction of alkene-tethered enones in the presence of an iron catalyst.
Collapse
Affiliation(s)
- Ying Xie
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, China
- School of Chemistry and Environmental Engineering, Sichuan University of Science & Engineering, Zigong, 643000, China
| | - Wei Huang
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, China
| | - Song Qin
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, China
| | - Shaomin Fu
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, China
| | - Bo Liu
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, China
| |
Collapse
|
126
|
Zhao M, He W, Zou LH, Wang D, Sun TY, Xia XF. Iron-catalyzed hydrogen atom transfer induced cyclization of 1,6-enynes for the synthesis of ketoximes: a combined experimental and computational study. Org Chem Front 2021. [DOI: 10.1039/d0qo01341b] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
An iron-catalyzed reductive radical cyclization/hydro-oximation of 1,6-enynes with tBuONO was developed, leading to functionalized benzofuran, benzothiophene, and cyclopentenyl-based ketoximes.
Collapse
Affiliation(s)
- Mingming Zhao
- Key Laboratory of Synthetic and Biological Colloids
- Ministry of Education
- School of Chemical and Material Engineering
- Jiangnan University
- Wuxi
| | - Wei He
- Key Laboratory of Synthetic and Biological Colloids
- Ministry of Education
- School of Chemical and Material Engineering
- Jiangnan University
- Wuxi
| | - Liang-Hua Zou
- School of Pharmaceutical Sciences
- Jiangnan University
- Wuxi
- China
| | - Dawei Wang
- Key Laboratory of Synthetic and Biological Colloids
- Ministry of Education
- School of Chemical and Material Engineering
- Jiangnan University
- Wuxi
| | | | - Xiao-Feng Xia
- Key Laboratory of Synthetic and Biological Colloids
- Ministry of Education
- School of Chemical and Material Engineering
- Jiangnan University
- Wuxi
| |
Collapse
|
127
|
Yang N, Fang Y, Xu F, Zhou R, Jin X, Zhang L, Shi J, Fang J, Wu H, Zhang Z. Application of the stabilization effect of a silyl group in radical-polar crossover reactions enabled by photoredox-neutral catalysis. Org Chem Front 2021. [DOI: 10.1039/d1qo00738f] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Taking advantage of the stabilization effect of a silyl group, with a bulky but positive nature, a range of less investigated organosilanes could be generally accessed via photoredox-catalysed radical-polar crossover reactions.
Collapse
Affiliation(s)
- Naiyuan Yang
- College of Chemistry and Chemical Engineering, Taiyuan University of Technology, No. 79 West Street Yingze, Taiyuan 030024, China
| | - Yewen Fang
- School of Materials and Chemical Engineering, Ningbo University of Technology, No. 201 Fenghua Road, Ningbo 315211, China
- Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, No. 345 Lingling Road, Shanghai 200032, China
| | - Fenfen Xu
- School of Materials and Chemical Engineering, Ningbo University of Technology, No. 201 Fenghua Road, Ningbo 315211, China
| | - Rong Zhou
- College of Chemistry and Chemical Engineering, Taiyuan University of Technology, No. 79 West Street Yingze, Taiyuan 030024, China
| | - Xiaoping Jin
- Department of Pharmaceutical Engineering, Zhejiang Pharmaceutical College, No. 888 Yinxian Avenue East, Ningbo 315100, China
| | - Li Zhang
- Department of Pharmaceutical Engineering, Zhejiang Pharmaceutical College, No. 888 Yinxian Avenue East, Ningbo 315100, China
| | - Jianxun Shi
- Department of Pharmaceutical Engineering, Zhejiang Pharmaceutical College, No. 888 Yinxian Avenue East, Ningbo 315100, China
| | - Jianghua Fang
- School of Materials and Chemical Engineering, Ningbo University of Technology, No. 201 Fenghua Road, Ningbo 315211, China
| | - Hao Wu
- School of Materials and Chemical Engineering, Ningbo University of Technology, No. 201 Fenghua Road, Ningbo 315211, China
| | - Zongyong Zhang
- School of Materials and Chemical Engineering, Ningbo University of Technology, No. 201 Fenghua Road, Ningbo 315211, China
| |
Collapse
|
128
|
Zhang H, Wang B, Xu H, Li FY, Wang JY. Synthesis of naphthodihydrofurans via an iron( iii)-catalyzed reduction radical cascade reaction. Org Chem Front 2021. [DOI: 10.1039/d1qo01041g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A convenient method for the synthesis of naphthodihydrofurans has been developed by iron(iii)-catalyzed cascade reaction of reducing radicals.
Collapse
Affiliation(s)
- Hua Zhang
- Department of Chemistry, Xihua University, P. R. China
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Bei Wang
- Department of Chemistry, Xihua University, P. R. China
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Hong Xu
- Department of Chemistry, Xihua University, P. R. China
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Fu-Yu Li
- Department of Chemistry, Xihua University, P. R. China
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Ji-Yu Wang
- Department of Chemistry, Xihua University, P. R. China
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China
| |
Collapse
|
129
|
Rana S, Biswas JP, Paul S, Paik A, Maiti D. Organic synthesis with the most abundant transition metal–iron: from rust to multitasking catalysts. Chem Soc Rev 2021; 50:243-472. [DOI: 10.1039/d0cs00688b] [Citation(s) in RCA: 85] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The promising aspects of iron in synthetic chemistry are being explored for three-four decades as a green and eco-friendly alternative to late transition metals. This present review unveils these rich iron-chemistry towards different transformations.
Collapse
Affiliation(s)
- Sujoy Rana
- Department of Chemistry
- University of North Bengal
- Darjeeling
- India
| | | | - Sabarni Paul
- Department of Chemistry
- University of North Bengal
- Darjeeling
- India
| | - Aniruddha Paik
- Department of Chemistry
- University of North Bengal
- Darjeeling
- India
| | - Debabrata Maiti
- Department of Chemistry
- IIT Bombay
- Mumbai-400076
- India
- Tokyo Tech World Research Hub Initiative (WRHI)
| |
Collapse
|
130
|
Ding Z, Wang Y, Liu W, Chen Y, Kong W. Diastereo- and Enantioselective Construction of Spirocycles by Nickel-Catalyzed Cascade Borrowing Hydrogen Cyclization. J Am Chem Soc 2020; 143:53-59. [PMID: 33356186 DOI: 10.1021/jacs.0c10055] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Zhengtian Ding
- The Center for Precision Synthesis (CPS), Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, People’s Republic of China
| | - Yiming Wang
- The Center for Precision Synthesis (CPS), Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, People’s Republic of China
| | - Wenfeng Liu
- The Center for Precision Synthesis (CPS), Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, People’s Republic of China
| | - Yate Chen
- The Center for Precision Synthesis (CPS), Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, People’s Republic of China
| | - Wangqing Kong
- The Center for Precision Synthesis (CPS), Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, People’s Republic of China
| |
Collapse
|
131
|
Abstract
A general method for the hydroalkylation of electron-rich terminal and non-terminal alkenes such as enol esters, alkenyl sulfides, enol ethers, silyl enol ethers, enamides and enecarbamates has been developed. The reactions are carried out at room temperature under air initiation in the presence of triethylborane acting as a chain transfer reagent and 4-tert-butylcatechol (TBC) as a source of hydrogen atom. The efficacy of the reaction is best explained by very favorable polar effects supporting the chain process and minimizing undesired polar reactions. The stereoselective hydroalkylation of chiral N-(alk-1-en-1-yl)oxazolidin-2-ones takes place with good to excellent diastereocontrol. Giese reaction not anymore limited to electron poor alkenes! A general method for the radical mediated hydroalkylation of electron rich alkenes including enol ethers, silylenolethers, enamides, and enecarbamates has been developed.![]()
Collapse
Affiliation(s)
- Qi Huang
- Department of Chemistry and Biochemistry, University of Bern Freiestrasse 3 CH-3012 Bern Switzerland
| | - Sankar Rao Suravarapu
- Department of Chemistry and Biochemistry, University of Bern Freiestrasse 3 CH-3012 Bern Switzerland
| | - Philippe Renaud
- Department of Chemistry and Biochemistry, University of Bern Freiestrasse 3 CH-3012 Bern Switzerland
| |
Collapse
|
132
|
Chatterjee B, Chang W, Werlé C. Molecularly Controlled Catalysis – Targeting Synergies Between Local and Non‐local Environments. ChemCatChem 2020. [DOI: 10.1002/cctc.202001431] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Basujit Chatterjee
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34–36 45470 Mülheim an der Ruhr Germany
- Ruhr University Bochum Universitätsstr. 150 44801 Bochum Germany
| | - Wei‐Chieh Chang
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34–36 45470 Mülheim an der Ruhr Germany
- Ruhr University Bochum Universitätsstr. 150 44801 Bochum Germany
| | - Christophe Werlé
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34–36 45470 Mülheim an der Ruhr Germany
- Ruhr University Bochum Universitätsstr. 150 44801 Bochum Germany
| |
Collapse
|
133
|
Zeng X, Shukla V, Boger DL. Divergent Total Syntheses of (-)-Pseudocopsinine and (-)-Minovincinine. J Org Chem 2020; 85:14817-14826. [PMID: 33205969 PMCID: PMC7718306 DOI: 10.1021/acs.joc.0c02493] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Herein, the first total syntheses of (-)-pseudocopsinine (1) and (-)-minovincine (3) from a common intermediate 8 are detailed, enlisting late-stage, hydrogen atom transfer (HAT)-mediated free radical bond formations (C20-C2 and C20-OH, respectively) that are unique to their core or structure. The approach to 1 features an Fe-mediated HAT reaction of the intermediate olefin 2, effecting a transannular C20-C2 free radical cyclization of a challenging substrate with formation of a strained [2.2.1] ring system and reaction of a poor acceptor tetrasubstituted alkene with a hindered secondary free radical to form a bond and quaternary center adjacent to another quaternary center. Central to the assemblage of their underlying Aspidosperma skeleton is a powerful [4 + 2]/[3 + 2] cycloaddition cascade of 1,3,4-oxadiazole 9, which affords the stereochemically rich and highly functionalized pentacyclic intermediate 8 as a single diastereomer in one step. The work extends the divergent total synthesis of four to now six different natural product alkaloid classes by distinguishing late stage key strategic bond formations within the underlying Aspidosperma core from the common intermediate 8. Together, the work represents use of strategic bond analysis combined with the strategy of divergent synthesis to access six different natural product classes from a single intermediate.
Collapse
Affiliation(s)
- Xianhuang Zeng
- Department of Chemistry and the Skaggs Institute for Chemical Biology, the Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Vyom Shukla
- Department of Chemistry and the Skaggs Institute for Chemical Biology, the Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Dale L. Boger
- Department of Chemistry and the Skaggs Institute for Chemical Biology, the Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| |
Collapse
|
134
|
Zhang H, Zhang GM, He S, Shi ZC, Zhang XM, Wang JY. A Construction of α-Alkenyl Lactones via Reduction Radical Cascade Reaction of Allyl Alcohols and Acetylenic Acids. Org Lett 2020; 22:8337-8344. [PMID: 33040535 DOI: 10.1021/acs.orglett.0c02973] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An iron-catalyzed cascade reaction of radical reduction of allyl alcohols and acetylenic acids to construct polysubstituted α-alkenyl lactones has been developed. In this paper, various allyl alcohols can form allyl ester intermediates and are further transformed into alkyl radicals, which form products through intramolecular reflex-Michael addition. In addition, this method can be used to prepare spirocycloalkenyl lactones. Interestingly, this protocol can be used to synthesize the skeleton structure of natural products. Moreover, the product can be further transformed into a β-methylene tetrahydrofuran and tetrahydrofuran diene.
Collapse
Affiliation(s)
- Hua Zhang
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China.,University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Guo-Min Zhang
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China.,University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Shuai He
- Southwest Minzu University, Chengdu 610041, P. R. China
| | | | - Xiao-Mei Zhang
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China
| | - Ji-Yu Wang
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China
| |
Collapse
|
135
|
Kattamuri PV, West JG. Hydrogenation of Alkenes via Cooperative Hydrogen Atom Transfer. J Am Chem Soc 2020; 142:19316-19326. [PMID: 33119986 DOI: 10.1021/jacs.0c09544] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Radical hydrogenation via hydrogen atom transfer (HAT) to alkenes is an increasingly important transformation for the formation of thermodynamic alkane isomers. Current single-catalyst methods require stoichiometric oxidant in addition to hydride (H-) source to function. Here we report a new approach to radical hydrogenation: cooperative hydrogen atom transfer (cHAT), where each hydrogen atom donated to the alkene arrives from a different catalyst. Further, these hydrogen atom (H•) equivalents are generated from complementary hydrogen atom precursors, with each alkane requiring one hydride (H-) and one proton (H+) equivalent and no added oxidants. Preliminary mechanistic study supports this reaction manifold and shows the intersection of metal-catalyzed HAT and thiol radical trapping HAT catalytic cycles to be essential for effective catalysis. Together, this unique catalyst system allows us to reduce a variety of unactivated alkene substrates to their respective alkanes in high yields and diastereoselectivities and introduces a new approach to radical hydrogenation.
Collapse
Affiliation(s)
- Padmanabha V Kattamuri
- Department of Chemistry, Rice University, BioScience Research Collaborative, Houston, Texas 77030, United States
| | - Julian G West
- Department of Chemistry, Rice University, BioScience Research Collaborative, Houston, Texas 77030, United States
| |
Collapse
|
136
|
Saladrigas M, Puig J, Bonjoch J, Bradshaw B. Iron-Catalyzed Radical Intermolecular Addition of Unbiased Alkenes to Aldehydes. Org Lett 2020; 22:8111-8115. [PMID: 33017537 DOI: 10.1021/acs.orglett.0c03081] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The intermolecular reductive radical coupling of aldehydes with nonactivated alkenes, employing metal hydride atom transfer (MHAT) catalysis with a combination of FeII and FeIII salts, is described. This constitutes the first use of aldehydes as viable acceptor groups in MHAT reactions. The insights gained in this study led to the reexamination of the previously reported intramolecular version of the reaction, and the addition of FeII salts allowed the development of a more efficient second-generation approach.
Collapse
Affiliation(s)
- Mar Saladrigas
- Laboratori de Quı́mica Orgànica, Facultat de Farmàcia, IBUB, Universitat de Barcelona, Av. Joan XXIII s/n, 08028-Barcelona, Spain
| | - Jordi Puig
- Laboratori de Quı́mica Orgànica, Facultat de Farmàcia, IBUB, Universitat de Barcelona, Av. Joan XXIII s/n, 08028-Barcelona, Spain
| | - Josep Bonjoch
- Laboratori de Quı́mica Orgànica, Facultat de Farmàcia, IBUB, Universitat de Barcelona, Av. Joan XXIII s/n, 08028-Barcelona, Spain
| | - Ben Bradshaw
- Laboratori de Quı́mica Orgànica, Facultat de Farmàcia, IBUB, Universitat de Barcelona, Av. Joan XXIII s/n, 08028-Barcelona, Spain
| |
Collapse
|
137
|
Yu X, Zhao H, Li P, Koh MJ. Iron-Catalyzed Tunable and Site-Selective Olefin Transposition. J Am Chem Soc 2020; 142:18223-18230. [DOI: 10.1021/jacs.0c08631] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Xiaolong Yu
- Department of Chemistry, National University of Singapore, 12 Science Drive 2, Republic of Singapore 117549
| | - Haonan Zhao
- Department of Chemistry, National University of Singapore, 12 Science Drive 2, Republic of Singapore 117549
| | - Ping Li
- Department of Chemistry, National University of Singapore, 12 Science Drive 2, Republic of Singapore 117549
| | - Ming Joo Koh
- Department of Chemistry, National University of Singapore, 12 Science Drive 2, Republic of Singapore 117549
| |
Collapse
|
138
|
Shevick SL, Wilson CV, Kotesova S, Kim D, Holland PL, Shenvi RA. Catalytic hydrogen atom transfer to alkenes: a roadmap for metal hydrides and radicals. Chem Sci 2020; 11:12401-12422. [PMID: 33520153 PMCID: PMC7810138 DOI: 10.1039/d0sc04112b] [Citation(s) in RCA: 122] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 09/28/2020] [Indexed: 12/12/2022] Open
Abstract
Hydrogen atom transfer from metal hydrides to alkenes appears to underlie widely used catalytic methods – the mechanistic implications are fascinating.
Hydrogen atom transfer from a metal hydride (MHAT) has emerged as a powerful, if puzzling, technique in chemical synthesis. In catalytic MHAT reactions, earth-abundant metal complexes generate stabilized and unstabilized carbon-centered radicals from alkenes of various substitution patterns with robust chemoselectivity. This perspective combines organic and inorganic perspectives to outline challenges and opportunities, and to propose working models to assist further developments. We attempt to demystify the putative intermediates, the basic elementary steps, and the energetic implications, especially for cage pair formation, collapse and separation. Distinctions between catalysts with strong-field (SF) and weak-field (WF) ligand environments may explain some differences in reactivity and selectivity, and provide an organizing principle for kinetics that transcends the typical thermodynamic analysis. This blueprint should aid practitioners who hope to enter and expand this exciting area of chemistry.
Collapse
Affiliation(s)
- Sophia L Shevick
- Department of Chemistry , Scripps Research , 10550 North Torrey Pines Road , La Jolla , CA 92037 , USA
| | - Conner V Wilson
- Department of Chemistry , Yale University , 225 Prospect St. , New Haven , CT 06511 , USA
| | - Simona Kotesova
- Department of Chemistry , Scripps Research , 10550 North Torrey Pines Road , La Jolla , CA 92037 , USA
| | - Dongyoung Kim
- Department of Chemistry , Yale University , 225 Prospect St. , New Haven , CT 06511 , USA
| | - Patrick L Holland
- Department of Chemistry , Yale University , 225 Prospect St. , New Haven , CT 06511 , USA
| | - Ryan A Shenvi
- Department of Chemistry , Scripps Research , 10550 North Torrey Pines Road , La Jolla , CA 92037 , USA
| |
Collapse
|
139
|
Swain M, Sadykhov G, Wang R, Kwon O. Dealkenylative Alkenylation: Formal σ-Bond Metathesis of Olefins. Angew Chem Int Ed Engl 2020; 59:17565-17571. [PMID: 32652746 PMCID: PMC8232059 DOI: 10.1002/anie.202005267] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 06/15/2020] [Indexed: 11/07/2022]
Abstract
The dealkenylative alkenylation of alkene C(sp3 )-C(sp2 ) bonds has been an unexplored area for C-C bond formation. Herein 64 examples of β-alkylated styrene derivatives, synthesized through the reactions of readily accessible feedstock olefins with β-nitrostyrenes by ozone/FeII -mediated radical substitutions, are reported. These reactions proceed with good efficiencies and high stereoselectivities under mild reaction conditions and tolerate an array of functional groups. Also demonstrated is the applicability of the strategy through several synthetic transformations of the products, as well as the syntheses of the natural product iso-moracin and the drug (E)-metanicotine.
Collapse
Affiliation(s)
- Manisha Swain
- Department of Chemistry and Biochemistry, University of California-Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - Gusein Sadykhov
- Department of Chemistry and Biochemistry, University of California-Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - Ruoxi Wang
- Department of Chemistry and Biochemistry, University of California-Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - Ohyun Kwon
- Department of Chemistry and Biochemistry, University of California-Los Angeles, Los Angeles, CA, 90095-1569, USA
| |
Collapse
|
140
|
Swain M, Sadykhov G, Wang R, Kwon O. Dealkenylative Alkenylation: Formal σ‐Bond Metathesis of Olefins. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202005267] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Manisha Swain
- Department of Chemistry and Biochemistry University of California—Los Angeles Los Angeles CA 90095-1569 USA
| | - Gusein Sadykhov
- Department of Chemistry and Biochemistry University of California—Los Angeles Los Angeles CA 90095-1569 USA
| | - Ruoxi Wang
- Department of Chemistry and Biochemistry University of California—Los Angeles Los Angeles CA 90095-1569 USA
| | - Ohyun Kwon
- Department of Chemistry and Biochemistry University of California—Los Angeles Los Angeles CA 90095-1569 USA
| |
Collapse
|
141
|
You C, Studer A. Synthesis of 1,3-Bis-(boryl)alkanes through Boronic Ester Induced Consecutive Double 1,2-Migration. Angew Chem Int Ed Engl 2020; 59:17245-17249. [PMID: 32579295 PMCID: PMC7540398 DOI: 10.1002/anie.202007541] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Indexed: 01/03/2023]
Abstract
A general and efficient approach for the preparation of 1,3-bis-(boryl)alkanes is introduced. It is shown that readily generated vinylboron ate complexes react with commercially available ICH2 Bpin to valuable 1,3-bis-(boryl)alkanes. The introduced transformation, which is experimentally easy to conduct, shows broad substrate scope and high functional-group tolerance. Mechanistic studies reveal that the reaction does not proceed via radical intermediates. Instead, an unprecedented boronic ester induced sequential bis-1,2-migration cascade is suggested.
Collapse
Affiliation(s)
- Cai You
- Organisch-Chemisches InstitutWestfälische Wilhelms-UniversitätCorrensstrasse 4048149MünsterGermany
| | - Armido Studer
- Organisch-Chemisches InstitutWestfälische Wilhelms-UniversitätCorrensstrasse 4048149MünsterGermany
| |
Collapse
|
142
|
|
143
|
Abstract
Daphnezomines A and B are structurally unusual Daphniphyllum alkaloids that contain a unique aza-adamantane core skeleton. Herein, a modular approach to these alkaloids is presented that exploits a diverse array of reaction strategies. Commencing from a chiral pool terpene-(S)-carvone, the azabicyclo[3.3.1]nonane backbone, which occurs widely in Daphniphyllum alkaloids, was easily accessed through a Sharpless allylic amination and a palladium-catalyzed oxidative cyclization. A protecting group enabled a stereoselective B-alkyl Suzuki-Miyaura coupling sequence and an Fe-mediated hydrogen atom transfer (HAT)-based radical cyclization were then applied to construct C6 and C8 stereocenters. A final epimer locking strategy enabled the assembly of the highly congested aza-adamantane core, thereby achieving the first total synthesis of (-)-daphnezomines A and B in 14 steps.
Collapse
Affiliation(s)
- Guangpeng Xu
- College of Life Sciences, Beijing Normal University, Beijing, 100875, China.,National Institute of Biological Sciences (NIBS), Beijing, 102206, China
| | - Jinbao Wu
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China
| | - Luyang Li
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China
| | - Yunan Lu
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China
| | - Chao Li
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China.,Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing, 100084, China
| |
Collapse
|
144
|
Leitch JA, Rossolini T, Rogova T, Dixon DJ. α-Tertiary Dialkyl Ether Synthesis via Reductive Photocatalytic α-Functionalization of Alkyl Enol Ethers. ACS Catal 2020. [DOI: 10.1021/acscatal.0c02584] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Jamie A. Leitch
- Department of Chemistry, University of Oxford, Chemistry Research
Laboratory, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Thomas Rossolini
- Department of Chemistry, University of Oxford, Chemistry Research
Laboratory, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Tatiana Rogova
- Department of Chemistry, University of Oxford, Chemistry Research
Laboratory, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Darren J. Dixon
- Department of Chemistry, University of Oxford, Chemistry Research
Laboratory, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| |
Collapse
|
145
|
Hu Y, Bai M, Yang Y, Tian J, Zhou Q. Rapid Access to Tetracyclic Core of Wortmannin via an Intramolecular Reductive Olefin Coupling Strategy. Org Lett 2020; 22:6308-6312. [PMID: 32806191 DOI: 10.1021/acs.orglett.0c02135] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A convergent approach to assemble the fused BCDE tetracyclic framework of wortmannin is presented. This route features a very challenging Suzuki-Miyaura coupling to prepare the fully functionalized furan intermediate, a Negishi-type acylation to unite the two enantio-enriched fragments, and a subsequent hydrogen-atom-transfer-initiated 6-endo radical cyclization to install the central cyclohexadienone moiety, which establishes the C10 all-carbon quaternary stereocenter.
Collapse
|
146
|
Ebisawa K, Izumi K, Ooka Y, Kato H, Kanazawa S, Komatsu S, Nishi E, Shigehisa H. Catalyst- and Silane-Controlled Enantioselective Hydrofunctionalization of Alkenes by Cobalt-Catalyzed Hydrogen Atom Transfer and Radical-Polar Crossover. J Am Chem Soc 2020; 142:13481-13490. [PMID: 32648757 DOI: 10.1021/jacs.0c05017] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The catalytic enantioselective synthesis of tetrahydrofurans, which are found in the structures of many biologically active natural products, via a transition-metal-catalyzed hydrogen atom transfer (TM-HAT) and radical-polar crossover (RPC) mechanism is described herein. Hydroalkoxylation of nonconjugated alkenes proceeded efficiently with excellent enantioselectivity (up to 94% ee) using a suitable chiral cobalt catalyst, N-fluoro-2,4,6-collidinium tetrafluoroborate, and diethylsilane. Surprisingly, the absolute configuration of the product was highly dependent on the steric hindrance of the silane. Slow addition of the silane, the dioxygen effect on the solvent, thermal dependence, and DFT calculation results supported the unprecedented scenario of two competing selective mechanisms. For the less-hindered diethylsilane, a high concentration of diffused carbon-centered radicals invoked diastereoenrichment of an alkylcobalt(III) intermediate by a radical chain reaction, which eventually determined the absolute configuration of the product. On the other hand, a more hindered silane resulted in less opportunity for a radical chain reaction, instead facilitating enantioselective kinetic resolution during the late-stage nucleophilic displacement of the alkylcobalt(IV) intermediate.
Collapse
Affiliation(s)
- Kousuke Ebisawa
- Faculty of Pharmacy, Musashino University, 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan
| | - Kana Izumi
- Faculty of Pharmacy, Musashino University, 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan
| | - Yuka Ooka
- Faculty of Pharmacy, Musashino University, 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan
| | - Hiroaki Kato
- Faculty of Pharmacy, Musashino University, 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan
| | - Sayori Kanazawa
- Faculty of Pharmacy, Musashino University, 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan
| | - Sayura Komatsu
- Faculty of Pharmacy, Musashino University, 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan
| | - Eriko Nishi
- Faculty of Pharmacy, Musashino University, 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan
| | - Hiroki Shigehisa
- Faculty of Pharmacy, Musashino University, 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan
| |
Collapse
|
147
|
You C, Studer A. Synthesis of 1,3‐Bis‐(boryl)alkanes through Boronic Ester Induced Consecutive Double 1,2‐Migration. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202007541] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Cai You
- Organisch-Chemisches Institut Westfälische Wilhelms-Universität Corrensstrasse 40 48149 Münster Germany
| | - Armido Studer
- Organisch-Chemisches Institut Westfälische Wilhelms-Universität Corrensstrasse 40 48149 Münster Germany
| |
Collapse
|
148
|
Liu L, Lee W, Youshaw CR, Yuan M, Geherty MB, Zavalij PY, Gutierrez O. Fe-catalyzed three-component dicarbofunctionalization of unactivated alkenes with alkyl halides and Grignard reagents. Chem Sci 2020; 11:8301-8305. [PMID: 34094183 PMCID: PMC8163237 DOI: 10.1039/d0sc02127j] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 07/21/2020] [Indexed: 12/30/2022] Open
Abstract
A highly chemoselective iron-catalyzed three-component dicarbofunctionalization of unactivated olefins with alkyl halides (iodides and bromides) and sp2-hybridized Grignard reagents is reported. The reaction operates under fast turnover frequency and tolerates a diverse range of sp2-hybridized nucleophiles (electron-rich and electron-deficient (hetero)aryl and alkenyl Grignard reagents), alkyl halides (tertiary alkyl iodides/bromides and perfluorinated bromides), and unactivated olefins bearing diverse functional groups including tethered alkenes, ethers, protected alcohols, aldehydes, and amines to yield the desired 1,2-alkylarylated products with high regiocontrol. Further, we demonstrate that this protocol is amenable for the synthesis of new (hetero)carbocycles including tetrahydrofurans and pyrrolidines via a three-component radical cascade cyclization/arylation that forges three new C-C bonds.
Collapse
Affiliation(s)
- Lei Liu
- Department of Chemistry and Biochemistry, University of Maryland College Park Maryland 20742 USA
| | - Wes Lee
- Department of Chemistry and Biochemistry, University of Maryland College Park Maryland 20742 USA
| | - Cassandra R Youshaw
- Department of Chemistry and Biochemistry, University of Maryland College Park Maryland 20742 USA
| | - Mingbin Yuan
- Department of Chemistry and Biochemistry, University of Maryland College Park Maryland 20742 USA
| | - Michael B Geherty
- Department of Chemistry and Biochemistry, University of Maryland College Park Maryland 20742 USA
| | - Peter Y Zavalij
- Department of Chemistry and Biochemistry, University of Maryland College Park Maryland 20742 USA
| | - Osvaldo Gutierrez
- Department of Chemistry and Biochemistry, University of Maryland College Park Maryland 20742 USA
| |
Collapse
|
149
|
Nagai T, Mimata N, Terada Y, Sebe C, Shigehisa H. Catalytic Dealkylative Synthesis of Cyclic Carbamates and Ureas via Hydrogen Atom Transfer and Radical-Polar Crossover. Org Lett 2020; 22:5522-5527. [PMID: 32633527 DOI: 10.1021/acs.orglett.0c01872] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Guided by the transition-metal hydrogen atom transfer and radical-polar crossover concepts, we developed a functional-group-tolerant and scalable method for the synthesis of cyclic carbamates and ureas, which are found in the structures of bioactive compounds. This method provides not only a common five-membered ring but also six-to-eight-membered ring products. The reaction proceeds through the intramolecular displacement of an alkylcobalt(IV) intermediate and dealkylation by 2,4,6-collidine; the activation energies of these steps were calculated by DFT.
Collapse
Affiliation(s)
- Takuya Nagai
- Faculty of Pharmacy, Musashino University 1-1-20 Shinmachi, Nishitokyo-shi, Tokyo 202-8585, Japan
| | - Nao Mimata
- Faculty of Pharmacy, Musashino University 1-1-20 Shinmachi, Nishitokyo-shi, Tokyo 202-8585, Japan
| | - Yoshihiro Terada
- Faculty of Pharmacy, Musashino University 1-1-20 Shinmachi, Nishitokyo-shi, Tokyo 202-8585, Japan
| | - Chikayoshi Sebe
- Faculty of Pharmacy, Musashino University 1-1-20 Shinmachi, Nishitokyo-shi, Tokyo 202-8585, Japan
| | - Hiroki Shigehisa
- Faculty of Pharmacy, Musashino University 1-1-20 Shinmachi, Nishitokyo-shi, Tokyo 202-8585, Japan
| |
Collapse
|
150
|
Kováč O, Zálešák F, J-Y D Bon D, Roiser L, Baar LV, Waser M, Pospíšil J. Trisubstituted Highly Activated Benzo[ d]thiazol-2-yl-sulfone-Containing Olefins as Building Blocks in Organic Synthesis. J Org Chem 2020; 85:7192-7206. [PMID: 32352285 DOI: 10.1021/acs.joc.0c00571] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
In this paper, we report the formation of highly electrophilic 1,1-deactivated olefins, their use as novel synthetic building blocks, and their transformation to structurally diverse molecular scaffolds. Synthesis of 1,1-deactivated olefins substituted with a BT-sulfonyl group and a carbonyl or nitrile, respectively, consists of unusual Ti(OPri)4-mediated Knoevenagel-type condensation and proceed in good to excellent yields. Generated olefins can be further transformed in a highly stereoselective manner and in good yields to various polyfunctionalized heterocycles and acyclic molecular scaffolds. Overall, the obtained structures are accessed in two to four steps starting from the (mostly) commercially available aldehydes. In addition, the presence of the BT-sulfonyl group in prepared structures allows for further chemoselective functionalization/post-synthetic transformations to provide structurally diverse final compounds.
Collapse
Affiliation(s)
- Ondřej Kováč
- Department of Organic Chemistry, Faculty of Science, Palacky University, tř. 17. listopadu 1192/12, CZ-771 46 Olomouc, Czech Republic
| | - František Zálešák
- Department of Organic Chemistry, Faculty of Science, Palacky University, tř. 17. listopadu 1192/12, CZ-771 46 Olomouc, Czech Republic
| | - David J-Y D Bon
- Department of Organic Chemistry, Faculty of Science, Palacky University, tř. 17. listopadu 1192/12, CZ-771 46 Olomouc, Czech Republic
| | - Lukas Roiser
- Institute of Organic Chemistry, Johannes Kepler University Linz, Altenbergerstraße 69, 4040 Linz, Austria
| | - Lubomír V Baar
- Department of Organic Chemistry, Faculty of Science, Palacky University, tř. 17. listopadu 1192/12, CZ-771 46 Olomouc, Czech Republic
| | - Mario Waser
- Institute of Organic Chemistry, Johannes Kepler University Linz, Altenbergerstraße 69, 4040 Linz, Austria
| | - Jiří Pospíšil
- Department of Organic Chemistry, Faculty of Science, Palacky University, tř. 17. listopadu 1192/12, CZ-771 46 Olomouc, Czech Republic.,Laboratory of Growth Regulators, Palacky University & Institute of Experimental Botany AS CR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic
| |
Collapse
|