1
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Ngo DT, Garwood JJA, Nagib DA. Cyclopropanation with Non-Stabilized Carbenes via Ketyl Radicals. J Am Chem Soc 2024; 146:24009-24015. [PMID: 39049431 DOI: 10.1021/jacs.4c07388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/27/2024]
Abstract
A radical mechanism enables simple and robust access to nonstabilized, alkyl iron carbenes for novel (2 + 1) cycloadditions. This Fe-catalyzed strategy employs simple, aliphatic aldehydes as carbene precursors in a practical, efficient, and stereoselective cyclopropanation. This air- and water-tolerant method permits convenient generation of iron carbenes and coupling to an exceptionally wide range of sterically and electronically diverse alkenes (nucleophilic, electrophilic, and neutral). A transient ketyl radical intermediate is key to accessing and harnessing this rare, alkyl iron carbene reactivity. Mechanistic experiments confirm the (a) intermediacy of ketyl radicals, (b) iron carbene formation by radical capture, and (c) nonconcerted nature of the (2 + 1) cycloaddition.
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Affiliation(s)
- Duong T Ngo
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Jacob J A Garwood
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - David A Nagib
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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2
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Luo Z, Zhang X, Li Z, Luo M, Zeng X. Mild ketyl radical generation and coupling with alkynes enabled by Cr catalysis: stereoselective access to E-exocyclic allyl alcohols. Chem Sci 2024; 15:11428-11434. [PMID: 39054998 PMCID: PMC11268464 DOI: 10.1039/d4sc02967d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Accepted: 06/07/2024] [Indexed: 07/27/2024] Open
Abstract
The mild catalytic generation of ketyl radicals for organic transformations remains an unsolved issue, although it facilitates the discovery of metal-catalyzed reactions with the features of high functional group tolerance. Here, we report the generation of the ketyl radicals and coupling with alkynes that was enabled by cost-effective chromium catalysis, allowing for the formation of valuable E-exocyclic allyl alcohols with high stereo- and chemoselectivity. A broad range of synthetically useful functional groups that are sensitive to strong reductants are compatible with the catalytic system, providing access to diverse substituted E-exocyclic allyl alcohols under mild conditions. Appended hydroxyl groups in products are facilely late-stage functionalized in accessing numerous derivatives, as well as the enantio-enrichment of exocyclic allyl alcohol using chiral ligands. Mechanistic studies suggest that bipyridine-ligated Cr(ii) complex serves as a reactive catalyst enabling the generation of the ketyl radical for coupling, giving vinyl radical, followed by the combination of Cr and transmetalation with Cp2ZrCl moiety in affording oxazirconiumacycle. This reaction provides a new opportunity for the mild formation of transient ketyl radicals from widely accessible aliphatic aldehydes for coupling with Earth-abundant metal catalysis.
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Affiliation(s)
- Zheng Luo
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University Chengdu 610064 China
| | - Xiaoyu Zhang
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University Chengdu 610064 China
| | - Zaiyang Li
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University Chengdu 610064 China
| | - Meiming Luo
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University Chengdu 610064 China
| | - Xiaoming Zeng
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University Chengdu 610064 China
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3
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Li C, Cheng J, Wan X, Li J, Zu W, Xu Y, Huang Y, Huo H. Ni/Photoredox-Catalyzed Enantioselective Acylation of α-Bromobenzoates with Aldehydes: A Formal Approach to Aldehyde-Aldehyde Cross-Coupling. J Am Chem Soc 2024; 146:19909-19918. [PMID: 38864298 DOI: 10.1021/jacs.4c03164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2024]
Abstract
The catalytic cross-coupling of identical or similar functional groups is a cornerstone strategy for carbon-carbon bond formation, as exemplified by renowned methods, such as olefin cross-metathesis, Kolbe electrolysis, and various cross-electrophile couplings. However, similar methodologies for coupling aldehydes─fundamental building blocks in organic synthesis─remain underdeveloped. While the benzoin-type condensation, first reported in 1832, offers a reliable route for aldehyde dimerization, the chemo- and enantioselective cross-coupling of nonidentical yet similar aldehydes remains an unsolved challenge. Herein, we report a unified platform enabling highly chemo- and enantioselective cross-coupling of aldehydes. By leveraging nickel photoredox catalysis in tandem with discrete activation strategies for each aldehyde, this mechanistically distinct approach facilitates the enantioselective union of an aldehyde-derived α-oxy radical with an acyl radical, photocatalytically generated from a distinct aldehyde. This novel strategy enables modular access to enantioenriched α-oxygenated ketones with two minimally differentiated aliphatic substituents, a feat not achievable with existing chemocatalytic or biocatalytic techniques. The synthetic utility of this method is demonstrated by its application in the streamlined asymmetric synthesis of various medicinally relevant molecules. Additionally, mechanistic investigations rationalize the versatility of nickel photoredox catalysis to exploit new pathways for addressing long-standing synthetic challenges.
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Affiliation(s)
- Chengyang Li
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Junliang Cheng
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Xiang Wan
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Jian Li
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Weisai Zu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Yumin Xu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Yongliang Huang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Haohua Huo
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
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4
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Jo J, Kim S, Park S, Kim S, Lee S, Choi JH, Chung WJ. Study on Pyridine-Boryl Radical-Promoted, Ketyl Radical-Mediated Carbon-Carbon Bond-Forming Reactions. J Org Chem 2024; 89:8985-9000. [PMID: 38861548 DOI: 10.1021/acs.joc.4c00946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2024]
Abstract
Ketyl radicals are synthetically versatile reactive species, but their applications have been hampered by harsh generation conditions employing highly reducing metals. Recently, the pyridine-boryl radical received wide attention as a promising organic reductant because of its mildness as well as convenience in handling. While probing the utility of the pyridine-boryl radical, our group observed facile pinacol coupling reactivity that had not been known at that time. This serendipitous finding was successfully rendered into a practical synthesis of tetraaryl-1,2-diols in up to 99% yield within 1 h. Subsequently, upon examinations of various reaction manifolds, a diastereoselective ketyl-olefin cyclization was accomplished to produce cycloalkanols such as trans-2-alkyl-1-indanols. Compared to the previous methods, the stereocontrolling ability was considerably enhanced by taking advantage of the structurally modifiable boryl group that would be present near the bond-forming site. In this full account, our synthetic efforts with the O-boryl ketyl radicals are disclosed in detail, covering the discovery, optimization, scope expansion, and mechanistic analysis, including density functional theory (DFT) calculations.
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Affiliation(s)
- Junhyuk Jo
- Department of Chemistry, GIST, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Somi Kim
- Department of Chemistry, GIST, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Seonyoung Park
- Department of Chemistry, GIST, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Seonyul Kim
- Department of Chemistry, GIST, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Sunggi Lee
- Department of Physics and Chemistry, DGIST, 333 Techno jungang-daero, Hyeonpung-eup, Dalseong-gun, Daegu 42988, Republic of Korea
| | - Jun-Ho Choi
- Department of Chemistry, GIST, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Won-Jin Chung
- Department of Chemistry, GIST, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
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5
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Kwak D, Jung S, Ha H, Han T, Ryu DH, Kim H, Kwak J. Electroreductive Access to 1,2-Aminoalcohols via Cross Aza-Pinacol Coupling of N-Acyl Diarylketimines and Aldehydes. Org Lett 2024; 26:2733-2738. [PMID: 37417822 DOI: 10.1021/acs.orglett.3c01543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/08/2023]
Abstract
We present highly efficient and operationally simple synthetic methods for 1,2-aminoalcohols via electroreductive cross aza-pinacol coupling between N-acyl diarylketimines and aldehydes. Preliminary mechanistic studies including cyclic voltammetry and density functional theory (DFT) calculations suggest that the reaction is instigated by selective electrochemical single electron transfer (SET) of N-acylketimines. The developed electrochemical protocol is compatible to biorelevant functional groups, enabling late-stage functionalization of pharmacophores.
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Affiliation(s)
- Dongmin Kwak
- Infectious Diseases Therapeutic Research Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
- Department of Chemistry, Sungkyunkwan University, Jangan, Suwon 16419, Republic of Korea
| | - Sehwa Jung
- Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Hyeonbin Ha
- Infectious Diseases Therapeutic Research Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
| | - Taedong Han
- Discovery Chemistry, Dong-A ST Research Institute, Yongin 17073, Republic of Korea
| | - Do Hyun Ryu
- Department of Chemistry, Sungkyunkwan University, Jangan, Suwon 16419, Republic of Korea
| | - Hyunwoo Kim
- Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
- Institute for Convergence Research and Education in Advanced Technology (I-CREATE), Yonsei University, Seoul 03722, Republic of Korea
| | - Jaesung Kwak
- Infectious Diseases Therapeutic Research Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
- Division of Medicinal Chemistry and Pharmacology, KRICT School, University of Science and Technology, Daejeon 34114, Republic of Korea
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6
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DeMuynck BM, Zhang L, Ralph EK, Nagib DA. Cyclopropanation of unactivated alkenes with non-stabilized iron carbenes. Chem 2024; 10:1015-1027. [PMID: 39070927 PMCID: PMC11281255 DOI: 10.1016/j.chempr.2024.01.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Cyclopropanes are ubiquitous in medicines, yet robust synthetic access to a wide range of sterically and electronically diverse analogs remains a challenge. To address the synthetic limitations of the most direct strategy, (2+1) cycloaddition, we sought to develop a variant that employs non-stabilized carbenes. We present herein an FeCl2-catalyzed cyclopropanation that uniquely employs aliphatic (enolizable) aldehydes as carbene precursors. A remarkably broad range of alkenes may be coupled with these non-stabilized, alkyl carbenes. This extensive scope enables the synthesis of novel classes of cyclopropanes bearing alkyl, benzyl, allyl, halide, and heteroatom substituents, as well as spirocyclic and fused bicycles. Over 40 examples illustrate the broad generality, efficiency, selectivity, functional group tolerance, and practical utility of this approach. Mechanistic insights, gathered from stereochemical probes and competition experiments, are included to reveal the applicability of this non-stabilized carbene route for novel cyclopropane synthesis.
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Affiliation(s)
- Bethany M. DeMuynck
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210
| | - Lumin Zhang
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210
| | - Emma K. Ralph
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210
| | - David A. Nagib
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210
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7
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Hu H, Shi Z, Guo X, Zhang FH, Wang Z. A Radical Approach for Asymmetric α-C-H Addition of N-Sulfonyl Benzylamines to Aldehydes. J Am Chem Soc 2024; 146:5316-5323. [PMID: 38364304 DOI: 10.1021/jacs.3c12043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2024]
Abstract
Efficient synthesis of enantioenriched amines is of great importance due to their significant synthetic and biological applications. Photoredox-mediated asymmetric α-amino C(sp3)-H functionalization offers an atom-economical and sustainable approach to access chiral amines. However, the development of analogous reactions is in its early stages, generally affording chiral amines with a single stereocenter. Herein, we present a novel synergistic triple-catalysis approach for the asymmetric α-C-H addition of readily available N-sulfonyl amines to aldehydes under mild conditions. This method allows for the efficient synthesis of a diverse array of valuable β-amino alcohols bearing vicinal stereocenters. Unlike previous reports, our protocol employs a radical approach using earth-abundant Cr catalysis. Quinuclidine plays a dual role by facilitating highly selective hydrogen-atom transfer to generate α-amino radicals and promoting the dissociation of the Cr-O bond, which is crucial for the overall catalytic cycle as evidenced by control, NMR, and DFT experiments. Preliminary mechanistic studies, including radical trapping, nonlinear effect, Stern-Volmer plot, kinetic isotope effect, and Hammett plot, offer valuable insights into the reaction pathway.
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Affiliation(s)
- Hui Hu
- Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, Hangzhou ,Zhejiang Province 310030, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, Hangzhou ,Zhejiang Province 310024, China
| | - Zhaoxin Shi
- Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, Hangzhou ,Zhejiang Province 310030, China
| | - Xiaochong Guo
- Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, Hangzhou ,Zhejiang Province 310030, China
| | - Feng-Hua Zhang
- Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, Hangzhou ,Zhejiang Province 310030, China
| | - Zhaobin Wang
- Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, Hangzhou ,Zhejiang Province 310030, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, Hangzhou ,Zhejiang Province 310024, China
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8
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Wen S, Bu J, Shen K. Dual Nickel- and Photoredox-Catalyzed Asymmetric Reductive Cross-Coupling To Access Chiral Secondary Benzylic Alcohols. J Org Chem 2024. [PMID: 38327084 DOI: 10.1021/acs.joc.3c02293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Transition-metal-catalyzed asymmetric cross-coupling represents a powerful strategy for C-C bond formation and the synthesis of enantiomerically pure molecules. Here, we report a dual nickel/photoredox-catalyzed enantioselective reductive cross-coupling of aryl halides with α-bromobenzoates, readily generated from aliphatic aldehydes, to provide diverse chiral secondary benzylic alcohols that are important motifs in bioactive natural products and pharmaceuticals. This dual catalytic system features mild conditions, good functional group tolerance, broad substrate scope, excellent enantiocontrol, and avoidance of stoichiometric metal reductants, presenting great potential for late-stage functionalization of complex molecules.
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Affiliation(s)
- Shun Wen
- Department of Radiology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Jie Bu
- Department of Radiology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Kun Shen
- Department of Radiology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
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9
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Zhang L, Nagib DA. Carbonyl cross-metathesis via deoxygenative gem-di-metal catalysis. Nat Chem 2024; 16:107-113. [PMID: 37697035 PMCID: PMC11090164 DOI: 10.1038/s41557-023-01333-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Accepted: 08/18/2023] [Indexed: 09/13/2023]
Abstract
Carbonyls and alkenes are versatile functional groups, whose reactivities are cornerstones of organic synthesis. The selective combination of two carbonyls to form an alkene-a carbonyl cross-metathesis-would be a valuable tool for their exchange. Yet, this important synthetic challenge remains unsolved. Although alkene/alkene and alkene/carbonyl cross-metathesis reactions are known, there is a lack of analogous methods for deoxygenative cross-coupling of two carbonyl compounds. Here we report a pair of strategies for the cross-metathesis of unbiased carbonyls, allowing an aldehyde to be chemo- and stereoselectively combined with another aldehyde or ketone. These mild, catalytic methods are promoted by earth-abundant metal salts and enable rapid access to an unprecedentedly broad range of either Z- or E-alkenes by two distinct mechanisms-entailing transiently generated (1) carbenes and ylides (via Fe catalysis) or (2) doubly nucleophilic gem-di-metallics (via Cr catalysis).
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Affiliation(s)
- Lumin Zhang
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA.
- Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China.
| | - David A Nagib
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA.
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10
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Latrache M, Lefebvre C, Abe M, Hoffmann N. Photochemically Induced Hydrogen Atom Transfer and Intramolecular Radical Cyclization Reactions with Oxazolones. J Org Chem 2023; 88:16435-16455. [PMID: 37983612 DOI: 10.1021/acs.joc.3c01951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Photochemically induced intramolecular hydrogen atom transfer in oxazolones is reported. An acetal or thioacetal function at the side chain acts as a hydrogen donor while the photochemical exited oxazolone is the acceptor. A one-step process─the electron and the proton are simultaneously transferred─is productive, while electron transfer followed by proton transfer is inefficient. Radical combination then takes place, leading to the formation of a C-C or C-N bond. The regioselectivity of the reaction is explained by the diradical/zwitterion dichotomy of radical intermediates at the singlet state. In the present case, the zwitterion structure plays a central role, and intramolecular electron transfer favors spin-orbit coupling and thus the intersystem crossing to the singlet state. The reaction of corresponding thioacetal derivatives is less efficient. In this case, photochemical electron transfer is competitive. The photoproducts resulting from C-C bond formation easily undergo stepwise thermal decarboxylation in which zwitterionic and polar transition states are involved. A computational study of this step has also been performed.
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Affiliation(s)
- Mohammed Latrache
- ICMR, Equipe de Photochimie, CNRS, Université de Reims Champagne-Ardenne, UFR Sciences, B.P. 1039, Reims 51687 France
| | - Corentin Lefebvre
- ICMR, Equipe de Photochimie, CNRS, Université de Reims Champagne-Ardenne, UFR Sciences, B.P. 1039, Reims 51687 France
| | - Manabu Abe
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
- Hiroshima Research Center for Photo-Drug-Delivery Systems (Hi-P-DDS), 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Norbert Hoffmann
- ICMR, Equipe de Photochimie, CNRS, Université de Reims Champagne-Ardenne, UFR Sciences, B.P. 1039, Reims 51687 France
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11
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Zhao CG, Du C, Guo Z, Li W, Han J, Xie J. Merging Manganese and Iminium Catalysis: Selective Hydroalkenylation of Unsaturated Aldehydes and Ketones. Angew Chem Int Ed Engl 2023; 62:e202312414. [PMID: 37696774 DOI: 10.1002/anie.202312414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 09/07/2023] [Accepted: 09/11/2023] [Indexed: 09/13/2023]
Abstract
The use of synergistic catalytic strategy can usually circumvent the intrinsic limitations of one catalytic system. In this communication, we disclose a cooperative catalysis strategy of manganese and iminium catalysis to realize selective hydroalkenylation of unsaturated aldehydes and ketones. Its success stems from the LUMO activation of unsaturated carbonyl compounds with secondary amines as the organocatalyst and the synergistic HOMO activation of alkenylboronic acids with Mn2 (CO)8 Br2 . This protocol exhibits several synthetic advances, e.g., simple operation, good functional group compatibility and good regioselectivity. The theoretical calculation indicates the migratory insertion followed by demetallation-isomerization process is kinetically more favorable than Michael-like nucleophilic addition. The use of proline-derived organocatalyst can deliver the desired products in moderate enantioselectivity.
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Affiliation(s)
- Chuan-Gang Zhao
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Chaoyu Du
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Zhenyu Guo
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Weipeng Li
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Jie Han
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Jin Xie
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
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12
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Zhong T, Gu C, Li Y, Huang J, Han J, Zhu C, Han J, Xie J. Manganese/Cobalt Bimetallic Relay Catalysis for Divergent Dehydrogenative Difluoroalkylation of Alkenes. Angew Chem Int Ed Engl 2023; 62:e202310762. [PMID: 37642584 DOI: 10.1002/anie.202310762] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 08/21/2023] [Accepted: 08/29/2023] [Indexed: 08/31/2023]
Abstract
The involvement of manganese radical for halogen atom transfer (XAT) reactions has been esteemed as one reliable method but encountered with limited catalytic models. In this paper, a novel bimetallic relay catalysis of Mn2 (CO)10 and cobaloxime has been developed for divergent dehydrogenative difluoroalkylation of alkenes using commercially available difluoroalkyl bromides. A wide range of structurally diverse terminal, cyclic and internal alkenes as well as tetrasubstituted alkenes are found to be good coupling partners to deliver difluoroalkylated allylic products and difluoromethylated cyclic products, accompanied with the production of H2 as the by-product. This bimetallic relay strategy features broad substrate scope, mild reaction conditions and excellent functional group compatibility. Its success represents an important step-forward to expedite the construction of a rich library of difluoroalkylated products.
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Affiliation(s)
- Tao Zhong
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Chengyihan Gu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Yuhang Li
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Jun Huang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Jian Han
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Chengjian Zhu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Jie Han
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Jin Xie
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
- State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources, College of Chemistry, Xinjiang University, Urumqi, 830017, China
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13
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Hu H, Wang Z. Cr-Catalyzed Asymmetric Cross Aza-Pinacol Couplings for β-Amino Alcohol Synthesis. J Am Chem Soc 2023; 145:20775-20781. [PMID: 37703906 DOI: 10.1021/jacs.3c08493] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/15/2023]
Abstract
Chiral β-amino alcohols are crucial structural motifs found in pharmaceuticals, natural products, and chiral ligands in asymmetric catalysis. Despite previous advances, the development of catalytic approaches to access β-amino alcohols bearing vicinal stereocenters from readily available chemicals remains a prominent challenge. Herein, we describe the Cr-catalyzed asymmetric cross aza-pinacol coupling of aldehydes and N-sulfonyl imines. This protocol proceeds in a radical-polar crossover manner from the intermediacy of an α-amino radical instead of a ketyl radical. Key to the success is using a chiral chromium catalyst, which plays a triple role in the chemoselective single-electron reduction of the imine, fast radical interception to inhibit radical addition to imines, and chemo- and stereoselective addition to aldehydes instead of imines. This method provides a modular and efficient approach to accessing diverse β-amino alcohols bearing vicinal stereocenters.
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Affiliation(s)
- Hui Hu
- Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Department of Chemistry School of Science, Westlake University, Hangzhou 310030, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, Hangzhou 310024, China
| | - Zhaobin Wang
- Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Department of Chemistry School of Science, Westlake University, Hangzhou 310030, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, Hangzhou 310024, China
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14
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Edgecomb JM, Alektiar SN, Cowper NGW, Sowin JA, Wickens ZK. Ketyl Radical Coupling Enabled by Polycyclic Aromatic Hydrocarbon Electrophotocatalysts. J Am Chem Soc 2023; 145:20169-20175. [PMID: 37676728 PMCID: PMC10787642 DOI: 10.1021/jacs.3c06347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/09/2023]
Abstract
Herein, we report a new class of electrophotocatalysts, polycyclic aromatic hydrocarbons, that promote the reduction of unactivated carbonyl compounds to generate versatile ketyl radical intermediates. This catalytic platform enables previously challenging intermolecular ketyl radical coupling reactions, including those that classic reductants (e.g., SmI2/HMPA) have failed to promote. More broadly, this study outlines an approach to fundamentally expand the array of reactive radical intermediates that can be generated via electrophotocatalysis by obviating the need for rapid mesolytic cleavage following substrate reduction.
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Affiliation(s)
- Joseph M Edgecomb
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Sara N Alektiar
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Nicholas G W Cowper
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Jennifer A Sowin
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Zachary K Wickens
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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15
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Liu YT, Fan YH, Mei Y, Li DJ, Jiang Y, Yu WH, Pan F. Chromium-Catalyzed Defluorinative Reductive Coupling of Aldehydes with gem-Difluoroalkenes. Org Lett 2023; 25:549-554. [PMID: 36637443 DOI: 10.1021/acs.orglett.3c00016] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Herein, a mild and convenient defluorinative reductive cross coupling of gem-difluoroalkenes with aliphatic aldehydes has been developed to afford diverse silyl-protected β-fluorinated allylic alcohols. The reaction is operationally simple and shows good functional group tolerance with moderate to excellent yields. The utility of this method is demonstrated by converting the products into various bioactive fluorinated compounds, showing its potential applications in drug discovery and biochemistry.
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Affiliation(s)
- Yu-Tao Liu
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610068, People's Republic of China
| | - Yu-Hang Fan
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610068, People's Republic of China
| | - Yan Mei
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610068, People's Republic of China
| | - Dong-Jie Li
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610068, People's Republic of China
| | - Yan Jiang
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610068, People's Republic of China
| | - Wen-Hao Yu
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610068, People's Republic of China
| | - Fei Pan
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610068, People's Republic of China
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16
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Gontala A, Huh H, Woo SK. Photoredox-Catalyzed Synthesis of β-Amino Alcohols: Hydroxymethylation of Imines with α-Silyl Ether as Hydroxymethyl Radical Precursor. Org Lett 2023; 25:21-26. [PMID: 36562568 DOI: 10.1021/acs.orglett.2c03633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Carbon-carbon bond formation is an efficient approach for the synthesis of amino alcohols using two simple starting materials. Herein, we present a novel method for a divergent synthesis of β-amino ethers and β-amino alcohols in a sequential one-pot protocol under high-efficiency, mild, and metal- or metal-free conditions. Especially, TMSCH2OPMP was developed as a synthetic equivalent of α-hydroxymethyl radical in an in situ photocatalyzed oxidative PMP group deprotection strategy under air. A preliminary mechanistic investigation provides evidence for reaction mechanism involving a photoinduced α-alkoxy methyl radical and superoxide.
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Affiliation(s)
- Arjun Gontala
- Department of Chemistry, University of Ulsan, 93 Daehak-Ro, Nam-Gu, Ulsan 44610, Korea
| | - Hyunho Huh
- Department of Chemistry, University of Ulsan, 93 Daehak-Ro, Nam-Gu, Ulsan 44610, Korea
| | - Sang Kook Woo
- Department of Chemistry, University of Ulsan, 93 Daehak-Ro, Nam-Gu, Ulsan 44610, Korea
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17
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Ji H, Lin D, Tai L, Li X, Shi Y, Han Q, Chen LA. Nickel-Catalyzed Enantioselective Coupling of Acid Chlorides with α-Bromobenzoates: An Asymmetric Acyloin Synthesis. J Am Chem Soc 2022; 144:23019-23029. [DOI: 10.1021/jacs.2c10072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Haiting Ji
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of New Power Batteries, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China
| | - Dengkai Lin
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of New Power Batteries, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China
| | - Lanzhu Tai
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of New Power Batteries, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China
| | - Xinyu Li
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of New Power Batteries, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China
| | - Yuxuan Shi
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of New Power Batteries, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China
| | - Qiaorong Han
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of New Power Batteries, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China
| | - Liang-An Chen
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of New Power Batteries, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China
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18
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Zhu C, Lee S, Chen H, Yue H, Rueping M. Reductive Cross‐Coupling of α‐Oxy Halides Enabled by Thermal Catalysis, Photocatalysis, Electrocatalysis, or Mechanochemistry. Angew Chem Int Ed Engl 2022; 61:e202204212. [DOI: 10.1002/anie.202204212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Indexed: 11/08/2022]
Affiliation(s)
- Chen Zhu
- KAUST Catalysis Center (KCC) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia
| | - Shao‐Chi Lee
- KAUST Catalysis Center (KCC) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia
| | - Haifeng Chen
- KAUST Catalysis Center (KCC) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia
| | - Huifeng Yue
- KAUST Catalysis Center (KCC) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia
| | - Magnus Rueping
- KAUST Catalysis Center (KCC) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia
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19
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West MS, Rousseaux SAL. Safe, selective, and scalable carbenes. Science 2022; 377:580-581. [PMID: 35926030 DOI: 10.1126/science.abq8253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The synthesis of reactive carbene intermediates is made simpler and safer.
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Affiliation(s)
- Michael S West
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, Toronto, ON, Canada
| | - Sophie A L Rousseaux
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, Toronto, ON, Canada
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20
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Zhang L, DeMuynck BM, Paneque AN, Rutherford JE, Nagib DA. Carbene reactivity from alkyl and aryl aldehydes. Science 2022; 377:649-654. [PMID: 35926031 PMCID: PMC9439075 DOI: 10.1126/science.abo6443] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Carbenes are highly enabling reactive intermediates that facilitate a diverse range of otherwise inaccessible chemistry, including small-ring formation and insertion into strong σ bonds. To access such valuable reactivity, reagents with high entropic or enthalpic driving forces are often used, including explosive (diazo) or unstable (gem-dihalo) compounds. Here, we report that common aldehydes are readily converted (via stable α-acyloxy halide intermediates) to electronically diverse (donor or neutral) carbenes to facilitate >10 reaction classes. This strategy enables safe reactivity of nonstabilized carbenes from alkyl, aryl, and formyl aldehydes via zinc carbenoids. Earth-abundant metal salts [iron(II) chloride (FeCl2), cobalt(II) chloride (CoCl2), copper(I) chloride (CuCl)] are effective catalysts for these chemoselective carbene additions to σ and π bonds.
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Affiliation(s)
- Lumin Zhang
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA
| | - Bethany M DeMuynck
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA
| | - Alyson N Paneque
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA
| | - Joy E Rutherford
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA
| | - David A Nagib
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA
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21
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Zhu C, Lee S, Chen H, Yue H, Rueping M. Reductive Cross‐Coupling of α‐Oxy Halides Enabled by Thermal Catalysis, Photocatalysis, Electrocatalysis, or Mechanochemistry. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202204212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Chen Zhu
- KAUST Catalysis Center (KCC) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia
| | - Shao‐Chi Lee
- KAUST Catalysis Center (KCC) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia
| | - Haifeng Chen
- KAUST Catalysis Center (KCC) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia
| | - Huifeng Yue
- KAUST Catalysis Center (KCC) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia
| | - Magnus Rueping
- KAUST Catalysis Center (KCC) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia
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22
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Bellotti P, Huang HM, Faber T, Laskar R, Glorius F. Catalytic defluorinative ketyl-olefin coupling by halogen-atom transfer. Chem Sci 2022; 13:7855-7862. [PMID: 35865891 PMCID: PMC9258324 DOI: 10.1039/d2sc02732a] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 06/09/2022] [Indexed: 12/11/2022] Open
Abstract
Ketyl-olefin coupling reactions stand as one of the fundamental chemical transformations in synthetic chemistry and have been widely employed in the generation of complex molecular architectures and natural product synthesis. However, catalytic ketyl-olefin coupling, until the recent development of photoredox chemistry and electrosynthesis through single-electron transfer mechanisms, has remained largely undeveloped. Herein, we describe a new approach to achieve catalytic ketyl-olefin coupling reactions by a halogen-atom transfer mechanism, which provides innovative and efficient access to various gem-difluorohomoallylic alcohols under mild conditions with broad substrate scope. Preliminary mechanistic experimental and computational studies demonstrate that this radical-to-polar crossover transformation could be achieved by sequentially orchestrated Lewis acid activation, halogen-atom transfer, radical addition, single-electron reduction and β-fluoro elimination.
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Affiliation(s)
- Peter Bellotti
- Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut Corrensstraße 36 48149 Münster Germany
| | - Huan-Ming Huang
- Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut Corrensstraße 36 48149 Münster Germany
- School of Physical Science and Technology, ShanghaiTech University Shanghai 201210 China
| | - Teresa Faber
- Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut Corrensstraße 36 48149 Münster Germany
| | - Ranjini Laskar
- Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut Corrensstraße 36 48149 Münster Germany
| | - Frank Glorius
- Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut Corrensstraße 36 48149 Münster Germany
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23
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Zhang C, Wang L, Shi H, Lin Z, Wang C. Iron-Catalyzed Allylic Defluorinative Ketone Olefin Coupling. Org Lett 2022; 24:3211-3216. [PMID: 35481351 DOI: 10.1021/acs.orglett.2c00979] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this protocol, we demonstrate our discovery that iron is able to efficiently catalyze the reductive allylic defluorinative ketyl olefin coupling reaction between α-trifluoromethyl alkenes and unactivated ketones. This operationally simple cross-electrophile reaction circumvents the use of pre-generated organometallics and allows for the synthesis of diverse functional-group-rich tertiary gem-difluorohomoallylic alcohols through a polarity-reversed strategy. Preliminary mechanistic studies support a mechanism that proceeds through a ketyl formation/olefin insertion/β-fluoro elimination sequence.
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Affiliation(s)
- Chang Zhang
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Lin Wang
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Hongzhang Shi
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Zhiyang Lin
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Chuan Wang
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China.,Center for Excellence in Molecular Synthesis of CAS, Hefei, Anhui 230026, P. R. China
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24
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Tay NES, Lehnherr D, Rovis T. Photons or Electrons? A Critical Comparison of Electrochemistry and Photoredox Catalysis for Organic Synthesis. Chem Rev 2022; 122:2487-2649. [PMID: 34751568 PMCID: PMC10021920 DOI: 10.1021/acs.chemrev.1c00384] [Citation(s) in RCA: 131] [Impact Index Per Article: 65.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Redox processes are at the heart of synthetic methods that rely on either electrochemistry or photoredox catalysis, but how do electrochemistry and photoredox catalysis compare? Both approaches provide access to high energy intermediates (e.g., radicals) that enable bond formations not constrained by the rules of ionic or 2 electron (e) mechanisms. Instead, they enable 1e mechanisms capable of bypassing electronic or steric limitations and protecting group requirements, thus enabling synthetic chemists to disconnect molecules in new and different ways. However, while providing access to similar intermediates, electrochemistry and photoredox catalysis differ in several physical chemistry principles. Understanding those differences can be key to designing new transformations and forging new bond disconnections. This review aims to highlight these differences and similarities between electrochemistry and photoredox catalysis by comparing their underlying physical chemistry principles and describing their impact on electrochemical and photochemical methods.
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Affiliation(s)
- Nicholas E S Tay
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Dan Lehnherr
- Process Research and Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Tomislav Rovis
- Department of Chemistry, Columbia University, New York, New York 10027, United States
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25
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Huang HM, Bellotti P, Erchinger JE, Paulisch TO, Glorius F. Radical Carbonyl Umpolung Arylation via Dual Nickel Catalysis. J Am Chem Soc 2022; 144:1899-1909. [PMID: 35041782 DOI: 10.1021/jacs.1c12199] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The formation of carbon-carbon bonds lies at the heart of synthetic organic chemistry and is widely applied to construct complex drugs, polymers, and materials. Despite its importance, catalytic carbonyl arylation remains comparatively underdeveloped, due to limited scope and functional group tolerance. Herein we disclose an umpolung strategy to achieve radical carbonyl arylation via dual catalysis. This redox-neutral approach provides a complementary method to construct Grignard-type products from (hetero)aryl bromides and aliphatic aldehydes, without the need for pre-functionalization. A sequential activation, hydrogen-atom transfer, and halogen atom transfer process could directly convert aldehydes to the corresponding ketyl-type radicals, which further react with aryl-nickel intermediates in an overall polarity-reversal process. This radical strategy tolerates─among others─acidic functional groups, heteroaryl motifs, and sterically hindered substrates and has been applied in the late-stage modification of drugs and natural products.
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Affiliation(s)
- Huan-Ming Huang
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany
| | - Peter Bellotti
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany
| | - Johannes E Erchinger
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany
| | - Tiffany O Paulisch
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany
| | - Frank Glorius
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany
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26
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Liu HC, Kong X, Gong XP, Li Y, Niu ZJ, Gou XY, Li XS, Wang YZ, Shi WY, Huang YC, Liu XY, Liang YM. Site-Selective Coupling of Remote C(sp3)−H/meta-C(sp2)−H Bonds Enabled by Ru/Photoredox Dual Catalysis and Mechanistic Studies. Chem Sci 2022; 13:5382-5389. [PMID: 35655562 PMCID: PMC9093131 DOI: 10.1039/d2sc00764a] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 04/11/2022] [Indexed: 11/21/2022] Open
Abstract
Construction of C(sp2)−C(sp3) bonds via regioselective coupling of C(sp2)−H/C(sp3)−H bonds is challenging due to the low reactivity and regioselectivity of C−H bonds. Here, a novel photoinduced Ru/photocatalyst-cocatalyzed regioselective cross-dehydrogenative coupling...
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Affiliation(s)
- Hong-Chao Liu
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou 730000 China
| | - Xiangtao Kong
- Henan Key Laboratory of New Optoelectronic Functional Materials, College of Chemistry and Chemical Engineering, Anyang Normal University Anyang 455000 China
| | - Xiao-Ping Gong
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou 730000 China
| | - Yuke Li
- Department of Chemistry and Centre for Scientific Modeling and Computation, Chinese University of Hong Kong Shatin Hong Kong China
| | - Zhi-Jie Niu
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou 730000 China
| | - Xue-Ya Gou
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou 730000 China
| | - Xue-Song Li
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou 730000 China
| | - Yu-Zhao Wang
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou 730000 China
| | - Wei-Yu Shi
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou 730000 China
| | - Yan-Chong Huang
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou 730000 China
| | - Xue-Yuan Liu
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou 730000 China
| | - Yong-Min Liang
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou 730000 China
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27
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Chen JJ, Zhang Y, Huang HM. Radical umpolung chemistry enabled by dual catalysis: concept and recent advances. Catal Sci Technol 2022. [DOI: 10.1039/d2cy01161a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a perspective on recent advances in radical umpolung chemistry; some selected examples in this area have been highlighted.
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Affiliation(s)
- Jun-Jie Chen
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Ying Zhang
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Huan-Ming Huang
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
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28
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Juliá F, Constantin T, Leonori D. Applications of Halogen-Atom Transfer (XAT) for the Generation of Carbon Radicals in Synthetic Photochemistry and Photocatalysis. Chem Rev 2021; 122:2292-2352. [PMID: 34882396 DOI: 10.1021/acs.chemrev.1c00558] [Citation(s) in RCA: 162] [Impact Index Per Article: 54.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The halogen-atom transfer (XAT) is one of the most important and applied processes for the generation of carbon radicals in synthetic chemistry. In this review, we summarize and highlight the most important aspects associated with XAT and the impact it has had on photochemistry and photocatalysis. The organization of the material starts with the analysis of the most important mechanistic aspects and then follows a subdivision based on the nature of the reagents used in the halogen abstraction. This review aims to provide a general overview of the fundamental concepts and main agents involved in XAT processes with the objective of offering a tool to understand and facilitate the development of new synthetic radical strategies.
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Affiliation(s)
- Fabio Juliá
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Timothée Constantin
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Daniele Leonori
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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29
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Song X, Meng S, Zhang H, Jiang Y, Chan ASC, Zou Y. Dibrominated addition and substitution of alkenes catalyzed by Mn 2(CO) 10. Chem Commun (Camb) 2021; 57:13385-13388. [PMID: 34823257 DOI: 10.1039/d1cc04534b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A practical method for the dibromination of alkenes without using molecular bromine is consistently appealing in organic synthesis. Herein, we report Mn-catalyzed dibrominated addition and substitution of alkenes only with N-bromosuccinimide, producing a variety of synthetically valuable dibrominated compounds in moderate to high yields.
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Affiliation(s)
- Xianheng Song
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China.
| | - Shanshui Meng
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China. .,Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, Guangzhou 510006, China
| | - Hong Zhang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China.
| | - Yi Jiang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China.
| | - Albert S C Chan
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China. .,Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, Guangzhou 510006, China
| | - Yong Zou
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China. .,Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, Guangzhou 510006, China
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30
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Gao X, Turek-Herman JR, Choi YJ, Cohen RD, Hyster TK. Photoenzymatic Synthesis of α-Tertiary Amines by Engineered Flavin-Dependent "Ene"-Reductases. J Am Chem Soc 2021; 143:19643-19647. [PMID: 34784482 PMCID: PMC10157440 DOI: 10.1021/jacs.1c09828] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
α-Tertiary amines are a common motif in pharmaceutically important molecules but are challenging to prepare using asymmetric catalysis. Here, we demonstrate engineered flavin-dependent 'ene'-reductases (EREDs) can catalyze radical additions into oximes to prepare this motif. Two different EREDs were evolved into competent catalysts for this transformation with high levels of stereoselectivity. Mechanistic studies indicate that the oxime contributes to the enzyme templated charge-transfer complex formed between the substrate and cofactor. These products can be further derivatized to prepare a variety of motifs, highlighting the versatility of ERED photoenzymatic catalysis for organic synthesis.
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Affiliation(s)
- Xin Gao
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Joshua R Turek-Herman
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States.,Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Young Joo Choi
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Ryan D Cohen
- Analytical Research & Development, Merck & Company Inc., Rahway, New Jersey 07065, United States
| | - Todd K Hyster
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States.,Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
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31
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Hui C, Brieger L, Strohmann C, Antonchick AP. Stereoselective Synthesis of Cyclobutanes by Contraction of Pyrrolidines. J Am Chem Soc 2021; 143:18864-18870. [PMID: 34748319 PMCID: PMC8603356 DOI: 10.1021/jacs.1c10175] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Here we report a contractive synthesis of multisubstituted cyclobutanes containing multiple stereocenters from readily accessible pyrrolidines using iodonitrene chemistry. Mediated by a nitrogen extrusion process, the stereospecific synthesis of cyclobutanes involves a radical pathway. Unprecedented unsymmetrical spirocyclobutanes were prepared successfully, and a concise, formal synthesis of the cytotoxic natural product piperarborenine B is reported.
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Affiliation(s)
- Chunngai Hui
- Max Planck Institute of Molecular Physiology, Department of Chemical Biology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany.,Technical University Dortmund, Faculty of Chemistry and Chemical Biology, Otto-Hahn-Strasse 6, 44221 Dortmund, Germany
| | - Lukas Brieger
- Technical University Dortmund, Faculty of Chemistry and Chemical Biology, Otto-Hahn-Strasse 6, 44221 Dortmund, Germany
| | - Carsten Strohmann
- Technical University Dortmund, Faculty of Chemistry and Chemical Biology, Otto-Hahn-Strasse 6, 44221 Dortmund, Germany
| | - Andrey P Antonchick
- Max Planck Institute of Molecular Physiology, Department of Chemical Biology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany.,Technical University Dortmund, Faculty of Chemistry and Chemical Biology, Otto-Hahn-Strasse 6, 44221 Dortmund, Germany.,Nottingham Trent University, School of Science and Technology, Department of Chemistry and Forensics, Clifton Lane, NG11 8NS Nottingham, United Kingdom
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32
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Li M, Banerjee K, Friestad GK. Diastereocontrol in Radical Addition to β-Benzyloxy Hydrazones: Revised Approach to Tubuvaline and Synthesis of O-Benzyltubulysin V Benzyl Ester. J Org Chem 2021; 86:15139-15152. [PMID: 34636574 PMCID: PMC8576829 DOI: 10.1021/acs.joc.1c01798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Indexed: 11/29/2022]
Abstract
Radical addition to chiral N-acylhydrazones has generated unusual amino acids tubuphenylalanine (Tup) and tubuvaline (Tuv) that are structural components of the tubulysin family of picomolar antimitotic agents and previously led to a tubulysin tetrapeptide analog with a C-terminal alcohol. To improve efficiency in this synthetic route to tubulysins, and to address difficulties in oxidation of the C-terminal alcohol, here we present two alternative routes to Tuv that (a) improve step economy, (b) provide modified conditions for Mn-mediated radical addition in the presence of aromatic heterocycles, and (c) expose an example of double diastereocontrol in radical addition to a β-benzyloxyhydrazone with broader implications for asymmetric amine synthesis via radical addition. An efficient coupling sequence affords 11-O-benzyltubulysin V benzyl ester.
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Affiliation(s)
- Manshu Li
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Koushik Banerjee
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Gregory K. Friestad
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
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33
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Nugent J, Sterling AJ, Frank N, Mousseau JJ, Anderson EA. Synthesis of α-Quaternary Bicyclo[1.1.1]pentanes through Synergistic Organophotoredox and Hydrogen Atom Transfer Catalysis. Org Lett 2021; 23:8628-8633. [PMID: 34699248 DOI: 10.1021/acs.orglett.1c03346] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Bicyclo[1.1.1]pentanes (BCPs) are important in drug design as sp3-rich bioisosteres of arenes and tert-butyl groups; however, the preparation of BCPs with adjacent quaternary carbons is barely known. We report a facile synthesis of α-quaternary BCPs using organophotoredox and hydrogen atom transfer catalysis in which α-keto radicals, generated through oxidation of β-ketocarbonyls, undergo efficient addition to [1.1.1]propellane. The BCP products can be transformed into a variety of useful derivatives, including enantioenriched BCPs featuring α-quaternary stereocenters.
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Affiliation(s)
- Jeremy Nugent
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Alistair J Sterling
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Nils Frank
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - James J Mousseau
- Pfizer Worldwide Research and Development, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Edward A Anderson
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
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34
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Guo Y, Cao Y, Song H, Liu Y, Wang Q. Photoredox relay-catalyzed gem-difluoroallylation of alkyl iodides. Chem Commun (Camb) 2021; 57:9768-9771. [PMID: 34486611 DOI: 10.1039/d1cc04284j] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Herein, a new example of relay catalysis, using a combination of Mn2(CO)10 and an iridium-based photocatalyst, is reported. In our relay catalytic reaction, the Mn catalyst and iridium-based photocatalyst catalyze the reaction at different stages in the desired sequence under the same reaction conditions, and do not inhibit each other. This convenient method transforms a broad scope of alkyl iodides into the corresponding gem-difluoroalkenes via C(sp3)-C(sp3) bond construction. The protocol has good functional group tolerance and is suitable for the late-stage modification of multifunctional complex molecules.
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Affiliation(s)
- Yuanqiang Guo
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, College of Chemistry, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, People's Republic of China.
| | - Yunpeng Cao
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, College of Chemistry, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, People's Republic of China.
| | - Hongjian Song
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, College of Chemistry, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, People's Republic of China.
| | - Yuxiu Liu
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, College of Chemistry, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, People's Republic of China.
| | - Qingmin Wang
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, College of Chemistry, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, People's Republic of China.
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35
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Abstract
Despite recent advancements in the selective generation and coupling of organic radical species, the alkoxycarbonyl radical remains underexplored relative to other carbon-containing radical species. Drawing inspiration from new strategies for generating acyl radical equivalents utilizing dual N-heterocyclic carbene catalysis and photocatalysis, we have prepared dimethylimidazolium esters that can function as an alkoxycarbonyl radical surrogate under photocatalytic conditions. We demonstrate the synthetic utility of these azolium-based partners through the preparation of esters arising from the coupling of this radical surrogate with an oxidatively generated alkyl radical.
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Affiliation(s)
- Joshua L Zhu
- Department of Chemistry, Northwestern University, Evanston, IL 60208, United States
| | - Karl A Scheidt
- Department of Chemistry, Northwestern University, Evanston, IL 60208, United States
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36
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Liu XG, Dong CS, Li F, Zhang B. Manganese-Mediated Direct Functionalization of Hantzsch Esters with Alkyl Iodides via an Aromatization-Dearomatization Strategy. Org Lett 2021; 23:4002-4007. [PMID: 33978430 DOI: 10.1021/acs.orglett.1c01210] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
We report, for the first time, manganese-mediated direct functionalization of the Hantzsch esters with readily accessible alkyl iodides through an aromatization-dearomatization strategy. Applying this protocol, a library of valuable 4-alkyl-1,4-dihydropyridines were facilely afforded in good yields. This simple and practical reaction proceeds under visible-light irradiation at room temperature and displays high functional-group compatibility. Additionally, the method is applicable for gram-scale synthesis and late-stage functionalization of complex molecules.
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Affiliation(s)
- Xian-Guan Liu
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China
| | - Ci-Shuang Dong
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China
| | - Fei Li
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China
| | - Bo Zhang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China
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