1
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Li Y, Bai H, Gao Q, Liu K, Han J, Li W, Zhu C, Xie J. Stereoselective benzylic C(sp 3)-H alkenylation enabled by metallaphotoredox catalysis. Chem Sci 2024; 15:12511-12516. [PMID: 39118628 PMCID: PMC11304817 DOI: 10.1039/d4sc02830a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Accepted: 06/27/2024] [Indexed: 08/10/2024] Open
Abstract
Selective activation of the benzylic C(sp3)-H bond is pivotal for the construction of complex organic frameworks. Achieving precise selectivity among C-H bonds with comparable energetic and steric profiles remains a profound synthetic challenge. Herein, we unveil a site- and stereoselective benzylic C(sp3)-H alkenylation utilizing metallaphotoredox catalysis. Various linear and cyclic (Z)-all-carbon tri- and tetrasubstituted olefins can be smoothly obtained. This strategy can be applied to complex substrates with multiple benzylic sites, previously deemed unsuitable due to the uncontrollable site-selectivity. In addition, sensitive functional groups such as terminal alkenyl and TMS groups are compatible under the mild conditions. The exceptional site-selectivity and broad substrate compatibility are attributed to the visible-light catalyzed relay electron transfer-proton transfer process. More importantly, we have extended this methodology to achieve enantioselective benzylic C(sp3)-H alkenylation, producing highly enantioenriched products. The applicability and scalability of our protocol are further validated through late-stage functionalization of complex structures and gram-scale operations, underscoring its practicality and robustness.
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Affiliation(s)
- Yantao 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
| | - Haonan Bai
- 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
| | - Qi Gao
- 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
| | - Kai Liu
- 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
| | - 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
| | - 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 450001 China
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry Shanghai 200032 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 Natural Medicines, China Pharmaceutical University Nanjing 211198 China
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2
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Ding Y, Wu J, Zhang T, Liu H, Huang H. Site-Selective Carbonylative Cyclization with Two Allylic C-H Bonds Enabled by Radical Differentiation. J Am Chem Soc 2024; 146:19635-19642. [PMID: 38980114 DOI: 10.1021/jacs.4c05360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Controlling the site-selectivity of C-H functionalization is of significant importance and a formidable undertaking in synthetic organic chemistry, motivating the continuing development of efficient and sustainable technologies for activating C-H bonds. However, methods that control the site-selectivity for double C-H functionalization are rare. We herein report a conceptually new method to achieve highly site-selective C-H functionalization by implementing a radical single-out strategy. Leveraging the steric hindrance-sensitive CO-insertion as the radical differentiation process, a site-selective and stereoselective carbonylative formal [2 + 2] cycloaddition of imines and alkenes by sequential double allylic C-H bond activation was established without special and complicated HAT-reagents. This reaction was compatible with a wide range of alkenes and imines with diverse skeletons to deliver allylic β-lactams that are of synthetic and medicinal interest.
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Affiliation(s)
- Yongzheng Ding
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, 230026, P. R. China
| | - Jianing Wu
- Key Laboratory of Precision and Intelligent Chemistry and Department of Chemistry, University of Science and Technology of China, Hefei, 230026, P. R. China
| | - Tianze Zhang
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, 230026, P. R. China
| | - Hongchi Liu
- Key Laboratory of Precision and Intelligent Chemistry and Department of Chemistry, University of Science and Technology of China, Hefei, 230026, P. R. China
| | - Hanmin Huang
- Key Laboratory of Precision and Intelligent Chemistry and Department of Chemistry, University of Science and Technology of China, Hefei, 230026, P. R. China
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3
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Mandal N, Mondal P, Mandal S, Datta A. Unlocking Enantioselectivity: Synergy of 2-Pyridone and Chiral Amino Acids in Pd-Catalyzed β-C(sp 3)-H Transformations. J Org Chem 2024; 89:9223-9232. [PMID: 38885175 DOI: 10.1021/acs.joc.4c00078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Abstract
Enantioselective C(sp3)-H activation has garnered significant attention in synthetic and computational chemistry. Chiral transient directing groups (TDGs) hold promise for enabling Pd(II)-catalyzed enantioselective C(sp3)-H functionalization. Despite the interest in this strategy, it presents a challenge because the stereogenic center on the chiral TDG is frequently distant from the C-H bond, leading to a mixture of functionalized products. Our computational study on Pd(II)-catalyzed enantioselective β-C(sp3)-H arylation of aliphatic ketone with chiral amino acids provides a sustainable route to synthesizing complex chiral molecular scaffolds. The cooperative action of 2-pyridone derivatives and chiral amino acids is crucial in promoting the enantio-discriminating C-H activation, oxidative addition, and reductive elimination steps. Using 5-nitro-2-pyridone as the optimal external ligand demonstrates its ability to achieve the highest level of enantioselection. In contrast, the modeled 3,5-di((trifluoromethyl)sulfonyl)-2-pyridone ligand facilitates the most straightforward C-H activation. This study underscores the pivotal role of the alkyl substituent at the α-position of the amino acid (TDG) in altering enantioselectivity.
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Affiliation(s)
- Nilangshu Mandal
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & B Raja S C Mullick Road, Kolkata 700032, India
| | - Partha Mondal
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & B Raja S C Mullick Road, Kolkata 700032, India
| | - Sucharita Mandal
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & B Raja S C Mullick Road, Kolkata 700032, India
| | - Ayan Datta
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & B Raja S C Mullick Road, Kolkata 700032, India
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4
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Tang L, Shen C, Hao S, Dong K. A Type of Chiral C 2-Symmetric Arylthiol Catalyst for Highly Enantioselective Anti-Markovnikov Hydroamination. J Am Chem Soc 2024; 146:16248-16256. [PMID: 38808533 DOI: 10.1021/jacs.4c04596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2024]
Abstract
The development of chiral hydrogen donor catalysts is fundamental in the expansion and innovation of asymmetric organocatalyzed reactions via an enantioselective hydrogen atom transfer (HAT) process. Herein, an unprecedented type of chiral C2-symmetric arylthiol catalysts derived from readily available enantiomeric lactate ester was developed. With these catalysts, an asymmetric anti-Markovnikov alkene hydroamination-cyclization reaction was established, affording a variety of pharmaceutically interesting 3-substituted piperidines with moderate to high enantioselectivity. Results of the designed control experiments and theoretical computation rationalized the origin of stereocontrol and disclosed the spatial effect of the moiety of chiral thiols on the enantioselectivity. We believed the facile synthesis, flexible tunability, and effective enantioselectivity-controlling capability of these catalysts would shed light on the development of versatile chiral HAT catalysts and related asymmetric reactions.
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Affiliation(s)
- Lin Tang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, State Key Laboratory of Petroleum Molecular & Process Engineering, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Chaoren Shen
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, State Key Laboratory of Petroleum Molecular & Process Engineering, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Shaoyu Hao
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, State Key Laboratory of Petroleum Molecular & Process Engineering, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Kaiwu Dong
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, State Key Laboratory of Petroleum Molecular & Process Engineering, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
- Chang-Kung Chuang Institute, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
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5
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Gao X, He H, Miao K, Zhang L, Ni SF, Li M, Guo W. Electrochemical Allylic C(sp 3)-H Isothiocyanation via [3,3]-Sigmatropic Rearrangement. Org Lett 2024; 26:4554-4559. [PMID: 38767297 DOI: 10.1021/acs.orglett.4c01463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
The direct allylic C(sp3)-H functionalization provides a straightforward protocol for the synthesis of valuable molecules. We report herein the first chemo- and site-selective method for allylic C(sp3)-H isothiocyanation of various internal alkenes under mild electrochemical conditions. This method exhibits broad functional group tolerance and excellent selectivity and can be applied for late-stage isothiocyanation of bioactive molecules. Combined experimental and computational studies indicate that the reaction proceeds via an unexpected [3,3]-sigmatropic rearrangement.
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Affiliation(s)
- Xuezhuang Gao
- College of Chemistry & Molecular Engineering, Qingdao University of Science & Technology, 53 Zhengzhou Road, 266042 Qingdao, P. R. China
| | - Hui He
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong, Shantou University, Shantou, 515063 Guangdong, P. R. China
| | - Kaili Miao
- College of Chemistry & Molecular Engineering, Qingdao University of Science & Technology, 53 Zhengzhou Road, 266042 Qingdao, P. R. China
| | - Linbao Zhang
- College of Chemistry & Molecular Engineering, Qingdao University of Science & Technology, 53 Zhengzhou Road, 266042 Qingdao, P. R. China
| | - Shao-Fei Ni
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong, Shantou University, Shantou, 515063 Guangdong, P. R. China
| | - Ming Li
- College of Chemistry & Molecular Engineering, Qingdao University of Science & Technology, 53 Zhengzhou Road, 266042 Qingdao, P. R. China
| | - Weisi Guo
- College of Chemistry & Molecular Engineering, Qingdao University of Science & Technology, 53 Zhengzhou Road, 266042 Qingdao, P. R. China
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6
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Zhou Y, Huang H. Fluoroalkylative Ketonization of Malononitrile-Tethered Alkenes via Nickel Electron-Shuttle and Lewis Acid Catalysis. Org Lett 2024; 26:4532-4536. [PMID: 38771933 DOI: 10.1021/acs.orglett.4c01415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2024]
Abstract
A binary Ni/Eu catalytic system has been developed, which enables an efficient reductive dicarbofunctionalization of unactivated alkenes with alkyl halides and malononitriles. The combination of Ni electron-shuttle catalysis with Eu(OTf)3, a non-redox-type Lewis acid, effectively activates the iminyl radicals, enabling the direct formation of the C(sp3)-C(sp3) bond and β-ketonitrile functionality across a variety of C═C double bonds. This reaction allows for the expedient synthesis of densely functionalized cyclic β-ketonitriles bearing all-carbon quaternary centers.
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Affiliation(s)
- Yangkun Zhou
- Key Laboratory of Precision and Intelligent Chemistry and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Hanmin Huang
- Key Laboratory of Precision and Intelligent Chemistry and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
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7
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Lee WCC, Zhang XP. Metalloradical Catalysis: General Approach for Controlling Reactivity and Selectivity of Homolytic Radical Reactions. Angew Chem Int Ed Engl 2024; 63:e202320243. [PMID: 38472114 PMCID: PMC11097140 DOI: 10.1002/anie.202320243] [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: 12/30/2023] [Revised: 03/11/2024] [Accepted: 03/12/2024] [Indexed: 03/14/2024]
Abstract
Since Friedrich Wöhler's groundbreaking synthesis of urea in 1828, organic synthesis over the past two centuries has predominantly relied on the exploration and utilization of chemical reactions rooted in two-electron heterolytic ionic chemistry. While one-electron homolytic radical chemistry is both rich in fundamental reactivities and attractive with practical advantages, the synthetic application of radical reactions has been long hampered by the formidable challenges associated with the control over reactivity and selectivity of high-energy radical intermediates. To fully harness the untapped potential of radical chemistry for organic synthesis, there is a pressing need to formulate radically different concepts and broadly applicable strategies to address these outstanding issues. In pursuit of this objective, researchers have been actively developing metalloradical catalysis (MRC) as a comprehensive framework to guide the design of general approaches for controlling over reactivity and stereoselectivity of homolytic radical reactions. Essentially, MRC exploits the metal-centered radicals present in open-shell metal complexes as one-electron catalysts for homolytic activation of substrates to generate metal-entangled organic radicals as the key intermediates to govern the reaction pathway and stereochemical course of subsequent catalytic radical processes. Different from the conventional two-electron catalysis by transition metal complexes, MRC operates through one-electron chemistry utilizing stepwise radical mechanisms.
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Affiliation(s)
- Wan-Chen Cindy Lee
- Department of Chemistry, Boston College, Merkert Chemistry Center, Chestnut Hill, Massachusetts 02467 (USA)
| | - X. Peter Zhang
- Department of Chemistry, Boston College, Merkert Chemistry Center, Chestnut Hill, Massachusetts 02467 (USA)
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8
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Hu X, Cheng-Sánchez I, Kong W, Molander GA, Nevado C. Nickel-catalysed enantioselective alkene dicarbofunctionalization enabled by photochemical aliphatic C-H bond activation. Nat Catal 2024; 7:655-665. [PMID: 38947227 PMCID: PMC11208155 DOI: 10.1038/s41929-024-01153-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 03/25/2024] [Indexed: 07/02/2024]
Abstract
The development of novel strategies to rapidly construct complex chiral molecules from readily available feedstocks is a long-term pursuit in the chemistry community. Radical-mediated alkene difunctionalizations represent an excellent platform towards this goal. However, asymmetric versions remain highly challenging, and more importantly, examples featuring simple hydrocarbons as reaction partners are elusive. Here we report an asymmetric three-component alkene dicarbofunctionalization capitalizing on the direct activation of C(sp 3)-H bonds through the combination of photocatalysed hydrogen atom transfer and nickel catalysis. This protocol provides an efficient platform for installing two vicinal carbon-carbon bonds across alkenes in an atom-economic fashion, providing a wide array of high-value chiral α-aryl/alkenyl carbonyls and phosphonates, as well as 1,1-diarylalkanes from ubiquitous alkane, ether and alcohol feedstocks. This method exhibits operational simplicity, broad substrate scope and excellent regioselectivity, chemoselectivity and enantioselectivity. The compatibility with bioactive motifs and expedient synthesis of pharmaceutically relevant molecules highlight the synthetic potential of this protocol.
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Affiliation(s)
- Xia Hu
- Department of Chemistry, University of Zurich, Zurich, Switzerland
| | | | - Wangqing Kong
- The Institute for Advanced Studies, Wuhan University, Wuhan, China
| | - Gary A. Molander
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA USA
| | - Cristina Nevado
- Department of Chemistry, University of Zurich, Zurich, Switzerland
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9
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Hu SP, Gao CH, Liu TM, Miao BY, Wang HC, Yu W, Han B. Integrating Olefin Carboamination and Hofmann-Löffler-Freytag Reaction by Radical Deconstruction of Hydrazonyl N-N Bond. Angew Chem Int Ed Engl 2024; 63:e202400168. [PMID: 38380865 DOI: 10.1002/anie.202400168] [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: 01/03/2024] [Revised: 02/13/2024] [Accepted: 02/19/2024] [Indexed: 02/22/2024]
Abstract
As a type of elementary organic compounds containing N-N single bond, hydrazone involved chemical conversions are extremely extensive, but they are mainly limited to N2-retention and N2-removal modes. We report herein an unprecedented protocol for the realization of division utilization of the N2-moiety of hydrazone by a radical facilitated N-N bond deconstruction strategy. This new conversion mode enables the successful combination of alkene carboamination and Hofmann-Löffler-Freytag reaction by the reaction of N-homoallyl mesitylenesulfonyl hydrazones with ethyl difluoroiodoacetate under photocatalytic redox neutral conditions. Mechanism studies reveal that the reaction undergoes a radical relay involving addition, crucial remote imino-N migration and H-atom transfer. Consequently, a series of structurally significant ϵ-N-sulphonamide-α,α-difluoro-γ-amino acid esters are efficiently produced via continuous C-C bond and dual C-N bonds forging.
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Affiliation(s)
- Si-Pei Hu
- State Key Laboratory of Applied Organic Chemistry (SKLAOC), College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Chen-Hui Gao
- State Key Laboratory of Applied Organic Chemistry (SKLAOC), College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Tu-Ming Liu
- State Key Laboratory of Applied Organic Chemistry (SKLAOC), College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Bing-Yang Miao
- State Key Laboratory of Applied Organic Chemistry (SKLAOC), College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Hong-Chen Wang
- State Key Laboratory of Applied Organic Chemistry (SKLAOC), College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Wei Yu
- State Key Laboratory of Applied Organic Chemistry (SKLAOC), College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Bing Han
- State Key Laboratory of Applied Organic Chemistry (SKLAOC), College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
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10
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Mallick S, Mandal T, Kumari N, Roy L, De Sarkar S. Divergent Electrochemical Synthesis of Indoles through pK a Regulation of Amides: Synthetic and Mechanistic Insights. Chemistry 2024; 30:e202304002. [PMID: 38290995 DOI: 10.1002/chem.202304002] [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: 11/30/2023] [Revised: 01/15/2024] [Accepted: 01/30/2024] [Indexed: 02/01/2024]
Abstract
A divergent synthetic approach to access highly substituted indole scaffolds is illustrated. By virtue of a tunable electrochemical strategy, distinct control over the C-3 substitution pattern was achieved by employing two analogous 2-styrylaniline precursors. The chemoselectivity is governed by the fine-tuning of the acidity of the amide proton, relying on the appropriate selection of N-protecting groups, and assisted by the reactivity of the electrogenerated intermediates. Detailed mechanistic investigations based on cyclic voltametric experiments and computational studies revealed the crucial role of water additive, which assists the proton-coupled electron transfer event for highly acidic amide precursors, followed by an energetically favorable intramolecular C-N coupling, causing exclusive fabrication of the C-3 unsubstituted indoles. Alternatively, the implementation of an electrogenerated cationic olefin activator delivers the C-3 substituted indoles through the preferential nucleophilic nature of the N-acyl amides. This electrochemical approach of judicious selection of N-protecting groups to regulate pKa/E° provides an expansion in the domain of switchable generation of heterocyclic derivatives in a sustainable fashion, with high regio- and chemoselectivity.
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Affiliation(s)
- Samrat Mallick
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246, India
| | - Tanumoy Mandal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246, India
| | - Nidhi Kumari
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246, India
| | - Lisa Roy
- Institute of Chemical Technology Mumbai-IOC Odisha Campus, Bhubaneswar, Bhubaneswar, 751013, India
| | - Suman De Sarkar
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246, India
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11
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Zhao Y, Zhang Z, Qi Z, Liu R. Palladium-catalyzed dehydrogenation of α-cyclohexene-substituted nitriles to α-aryl nitriles. Chem Commun (Camb) 2024; 60:3425-3428. [PMID: 38441208 DOI: 10.1039/d4cc00326h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/22/2024]
Abstract
The development of a practical, inexpensive, and cyanide-free method for synthesizing α-aryl nitriles remains a challenging goal in synthetic chemistry. Here, we report an approach for synthesizing α-aryl nitriles toward achieving this goal, by which α-cyclohexenyl acetonitriles and α-cyclohexenyl alkenyl nitriles are dehydrogenated to α-aryl nitriles.
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Affiliation(s)
- Yinglin Zhao
- School of Pharmacy, East China University of Science and Technology, Engineering Research Center of Pharmaceutical Process Chemistry, Meilong Road 130, Shanghai 200237, China.
| | - Zhida Zhang
- School of Pharmacy, East China University of Science and Technology, Engineering Research Center of Pharmaceutical Process Chemistry, Meilong Road 130, Shanghai 200237, China.
| | - Zehuan Qi
- School of Pharmacy, East China University of Science and Technology, Engineering Research Center of Pharmaceutical Process Chemistry, Meilong Road 130, Shanghai 200237, China.
| | - Renhua Liu
- School of Pharmacy, East China University of Science and Technology, Engineering Research Center of Pharmaceutical Process Chemistry, Meilong Road 130, Shanghai 200237, China.
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12
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Huang C, Qin YS, Wang CL, Xiao P, Tang S, Liu HJ, Wei Z, Cai H. Visible light-induced C(sp 3)-H azolation of ethers via radical-polar crossover. Chem Commun (Camb) 2024; 60:2669-2672. [PMID: 38351890 DOI: 10.1039/d3cc06210d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2024]
Abstract
Reported herein is a photochemical strategy for C(sp3)-H azolation of ethers via a hydrogen-atom transfer and radical-polar crossover process, offering efficient access to valuable N-alkylated azoles under visible-light irradiation. The protocol is metal-free and photocatalyst-free, and exhibits good to excellent yields and broad substrate scope with regard to azoles. EPR experiments provide evidence for the formation of intermediates formed in situ.
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Affiliation(s)
- Cheng Huang
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, P. R. China.
| | - Yu-Shu Qin
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, P. R. China.
| | - Chen-Lu Wang
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, P. R. China.
| | - Peng Xiao
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, P. R. China.
| | - Sheng Tang
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, P. R. China.
| | - Hong-Jun Liu
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, P. R. China.
| | - Zhenhong Wei
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, P. R. China.
| | - Hu Cai
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, P. R. China.
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13
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Wang L, Wang CL, Li ZH, Lian PF, Kang JC, Zhou J, Hao Y, Liu RX, Bai HY, Zhang SY. Cooperative Cu/azodiformate system-catalyzed allylic C-H amination of unactivated internal alkenes directed by aminoquinoline. Nat Commun 2024; 15:1483. [PMID: 38374064 PMCID: PMC10876528 DOI: 10.1038/s41467-024-45875-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 02/07/2024] [Indexed: 02/21/2024] Open
Abstract
Aliphatic allylic amines are common in natural products and pharmaceuticals. The oxidative intermolecular amination of C(sp3)-H bonds represents one of the most straightforward strategies to construct these motifs. However, the utilization of widely internal alkenes with amines in this transformation remains a synthetic challenge due to the inefficient coordination of metals to internal alkenes and excessive coordination with aliphatic and aromatic amines, resulting in decreasing the reactivity of the catalyst. Here, we present a regioselective Cu-catalyzed oxidative allylic C(sp3)-H amination of internal olefins with azodiformates to these problems. A removable bidentate directing group is used to control the regiochemistry and stabilize the π-allyl-metal intermediate. Noteworthy is the dual role of azodiformates as both a nitrogen source and an electrophilic oxidant for the allylic C-H activation. This protocol features simple conditions, remarkable scope and functional group tolerance as evidenced by >40 examples and exhibits high regioselectivity and excellent E/Z selectivity.
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Affiliation(s)
- Le Wang
- Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, & Key Laboratory of Green and High-End Utilization of Salt Lake Resources, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Cheng-Long Wang
- Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, & Key Laboratory of Green and High-End Utilization of Salt Lake Resources, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Zi-Hao Li
- Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, & Key Laboratory of Green and High-End Utilization of Salt Lake Resources, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Peng-Fei Lian
- Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, & Key Laboratory of Green and High-End Utilization of Salt Lake Resources, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Jun-Chen Kang
- Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, & Key Laboratory of Green and High-End Utilization of Salt Lake Resources, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Jia Zhou
- Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, & Key Laboratory of Green and High-End Utilization of Salt Lake Resources, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Yu Hao
- Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, & Key Laboratory of Green and High-End Utilization of Salt Lake Resources, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Ru-Xin Liu
- Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, & Key Laboratory of Green and High-End Utilization of Salt Lake Resources, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - He-Yuan Bai
- Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, & Key Laboratory of Green and High-End Utilization of Salt Lake Resources, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Shu-Yu Zhang
- Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, & Key Laboratory of Green and High-End Utilization of Salt Lake Resources, Shanghai Jiao Tong University, Shanghai, 200240, PR China.
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14
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Wang M, Huang Y, Hu P. Terminal C(sp 3)-H borylation through intermolecular radical sampling. Science 2024; 383:537-544. [PMID: 38300993 DOI: 10.1126/science.adj9258] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 01/02/2024] [Indexed: 02/03/2024]
Abstract
Hydrogen atom transfer (HAT) processes can overcome the strong bond dissociation energies (BDEs) of inert C(sp3)-H bonds and thereby convert feedstock alkanes into value-added fine chemicals. Nevertheless, the high reactivity of HAT reagents, coupled with the small differences among various C(sp3)-H bond strengths, renders site-selective transformations of straight-chain alkanes a great challenge. Here, we present a photocatalytic intermolecular radical sampling process for the iron-catalyzed borylation of terminal C(sp3)-H bonds in substrates with small steric hindrance, including unbranched alkanes. Mechanistic investigations have revealed that the reaction proceeds through a reversible HAT process, followed by a selective borylation of carbon radicals. A boron-sulfoxide complex may contribute to the high terminal regioselectivity observed.
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Affiliation(s)
- Miao Wang
- Institute of Green Chemistry and Molecular Engineering, Lehn Institute of Functional Materials, School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China
| | - Yahao Huang
- Institute of Green Chemistry and Molecular Engineering, Lehn Institute of Functional Materials, School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China
| | - Peng Hu
- Institute of Green Chemistry and Molecular Engineering, Lehn Institute of Functional Materials, School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China
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15
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Mandal M, Buss JA, Chen SJ, Cramer CJ, Stahl SS. Mechanistic insights into radical formation and functionalization in copper/ N-fluorobenzenesulfonimide radical-relay reactions. Chem Sci 2024; 15:1364-1373. [PMID: 38274066 PMCID: PMC10806759 DOI: 10.1039/d3sc03597b] [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: 07/13/2023] [Accepted: 12/09/2023] [Indexed: 01/27/2024] Open
Abstract
Copper-catalysed radical-relay reactions that employ N-fluorobenzenesulfonimide (NFSI) as the oxidant have emerged as highly effective methods for C(sp3)-H functionalization. Herein, computational studies are paired with experimental data to investigate a series of key mechanistic features of these reactions, with a focus on issues related to site-selectivity, enantioselectivity, and C-H substrate scope. (1) The full reaction energetics of enantioselective benzylic C-H cyanation are probed, and an adduct between Cu and the N-sulfonimidyl radical (˙NSI) is implicated as the species that promotes hydrogen-atom transfer (HAT) from the C-H substrate. (2) Benzylic versus 3° C-H site-selectivity is compared with different HAT reagents: Cu/˙NSI, ˙OtBu, and Cl˙, and the data provide insights into the high selectivity for benzylic C-H bonds in Cu/NFSI-catalyzed C-H functionalization reactions. (3) The energetics of three radical functionalization pathways are compared, including radical-polar crossover (RPC) to generate a carbocation intermediate, reductive elimination from a formal CuIII organometallic complex, and radical addition to a Cu-bound ligand. The preferred mechanism is shown to depend on the ligands bound to copper. (4) Finally, the energetics of three different pathways that convert benzylic C-H bonds into benzylic cations are compared, including HAT/ET (ET = electron transfer), relevant to the RPC mechanism with Cu/NFSI; hydride transfer, involved in reactions with high-potential quinones; and sequential ET/PT/ET (PT = proton transfer), involved in catalytic photoredox reactions. Collectively, the results provide mechanistic insights that establish a foundation for further advances in radical-relay C-H functionalization reactions.
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Affiliation(s)
- Mukunda Mandal
- Department of Chemistry, Chemical Theory Center, and Supercomputing Institute, University of Minnesota 207 Pleasant Street SE Minneapolis MN 55455 USA
- Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
| | - Joshua A Buss
- Department of Chemistry, University of Wisconsin-Madison 1101 University Avenue Madison WI 53706 USA
| | - Si-Jie Chen
- Department of Chemistry, University of Wisconsin-Madison 1101 University Avenue Madison WI 53706 USA
| | - Christopher J Cramer
- Department of Chemistry, Chemical Theory Center, and Supercomputing Institute, University of Minnesota 207 Pleasant Street SE Minneapolis MN 55455 USA
| | - Shannon S Stahl
- Department of Chemistry, University of Wisconsin-Madison 1101 University Avenue Madison WI 53706 USA
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16
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Wei Y, Wang Z, Wang K, Qiu JK, Wang Z, Li H, Duan X, Guo K, Bao X, Wu X. Copper-Catalyzed Radical Allene C(sp 2 )-H Cyanation. Angew Chem Int Ed Engl 2024; 63:e202317132. [PMID: 38038249 DOI: 10.1002/anie.202317132] [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: 11/10/2023] [Revised: 11/30/2023] [Accepted: 12/01/2023] [Indexed: 12/02/2023]
Abstract
While the hydrogen atom abstraction (HAA) from C(sp3 )-H bond has been well explored, the radical-mediated chemo- and regio-selective functionalization of allenic C(sp2 )-H bond via direct HAA from C(sp2 )-H bond of allene remains an unsolved challenge in synthetic chemistry. This is primarily due to inherent challenges with addition of radical intermediates to allenes, regioselectivity of HAA process, instability of allenyl radical toward propargyl radical et al. Herein, we report a copper catalyzed allenic C(sp2 )-H cyanation of an array of tri- and di-substituted allenes with exceptional site-selectivity, while mono-substituted allene was successfully cyanated, albeit with a low yield. In the developed strategy, steric N-fluoro-N-alkylsulfonamide, serving as precursor of hydrogen atom abstractor, plays a crucial role in achieving the desired regioselectivity and avoiding addition of N-centered radical to allene.
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Affiliation(s)
- Youhao Wei
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 Ren-Ai Road, Suzhou, Jiangsu, 215123, China
| | - Zheng Wang
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 Ren-Ai Road, Suzhou, Jiangsu, 215123, China
| | - Kaifeng Wang
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 Ren-Ai Road, Suzhou, Jiangsu, 215123, China
| | - Jiang-Kai Qiu
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Zhaoshan Wang
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 Ren-Ai Road, Suzhou, Jiangsu, 215123, China
| | - Haotian Li
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 Ren-Ai Road, Suzhou, Jiangsu, 215123, China
| | - Xiu Duan
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Kai Guo
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Xiaoguang Bao
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 Ren-Ai Road, Suzhou, Jiangsu, 215123, China
| | - Xinxin Wu
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 Ren-Ai Road, Suzhou, Jiangsu, 215123, China
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17
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Cheng Z, Yang T, Li C, Deng Y, Zhang F, Chen P, Lin Z, Ma S, Liu G. Site-Selective sp 2 C-H Cyanation of Allenes via Copper-Catalyzed Radical Relay. J Am Chem Soc 2023; 145:25995-26002. [PMID: 38011726 DOI: 10.1021/jacs.3c11368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Compared with the extensively reported hydrogen atom transfer (HAT) at sp3 C-H, abstraction of hydrogen atoms at the sp2 carbon is extremely rare. Here, we communicate the site-selective cyanation of the sp2 C-H bond of allenes using the strategy of copper-catalyzed radical relay. The reactions afford various allenyl nitriles directly from simple allenes with a broad substrate scope and a remarkable functional group compatibility under mild conditions. These reactions exhibit excellent site-selectivity toward sp2 C-H, which can be attributed to the unique pocket created by the Cu-bound nitrogen-centered radical. The favorable HAT on sp2 C-H is due to crucial hydrogen bonding between the fluoride bonded to the Cu(II) center and the hydrogen atom at the allylic position. These features enable the late-stage functionalization of druglike bioactive molecules containing an allene motif.
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Affiliation(s)
- Zhongming Cheng
- State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Tilong Yang
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Can Li
- State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Yunshun Deng
- Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Fangjia Zhang
- State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Pinhong Chen
- State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Zhenyang Lin
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Shengming Ma
- State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Guosheng Liu
- State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
- Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
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18
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Wang CL, Wang J, Jin JK, Li B, Phang YL, Zhang FL, Ye T, Xia HM, Hui LW, Su JH, Fu Y, Wang YF. Boryl radical catalysis enables asymmetric radical cycloisomerization reactions. Science 2023; 382:1056-1065. [PMID: 38033072 DOI: 10.1126/science.adg1322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 10/25/2023] [Indexed: 12/02/2023]
Abstract
The development of functionally distinct catalysts for enantioselective synthesis is a prominent yet challenging goal of synthetic chemistry. In this work, we report a family of chiral N-heterocyclic carbene (NHC)-ligated boryl radicals as catalysts that enable catalytic asymmetric radical cycloisomerization reactions. The radical catalysts can be generated from easily prepared NHC-borane complexes, and the broad availability of the chiral NHC component provides substantial benefits for stereochemical control. Mechanistic studies support a catalytic cycle comprising a sequence of boryl radical addition, hydrogen atom transfer, cyclization, and elimination of the boryl radical catalyst, wherein the chiral NHC subunit determines the enantioselectivity of the radical cyclization. This catalysis allows asymmetric construction of valuable chiral heterocyclic products from simple starting materials.
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Affiliation(s)
- Chang-Ling Wang
- Key Laboratory of Precision and Intelligent Chemistry, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jie Wang
- Key Laboratory of Precision and Intelligent Chemistry, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Ji-Kang Jin
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Bin Li
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Yee Lin Phang
- Key Laboratory of Precision and Intelligent Chemistry, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Feng-Lian Zhang
- Key Laboratory of Precision and Intelligent Chemistry, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Tian Ye
- Key Laboratory of Precision and Intelligent Chemistry, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Hui-Min Xia
- Key Laboratory of Precision and Intelligent Chemistry, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Li-Wen Hui
- Key Laboratory of Precision and Intelligent Chemistry, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Ji-Hu Su
- Chinese Academy of Sciences Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Yao Fu
- Key Laboratory of Precision and Intelligent Chemistry, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Yi-Feng Wang
- Key Laboratory of Precision and Intelligent Chemistry, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
- State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, China
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19
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Nong ZS, Chen XR, Wang PS, Hong X, Gong LZ. Enantioconvergent Palladium-Catalyzed Alkylation of Tertiary Allylic C-H Bonds. Angew Chem Int Ed Engl 2023; 62:e202312547. [PMID: 37752890 DOI: 10.1002/anie.202312547] [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: 08/25/2023] [Revised: 09/26/2023] [Accepted: 09/27/2023] [Indexed: 09/28/2023]
Abstract
Enantioconvergent catalysis enables the conversion of racemic molecules into a single enantiomer in perfect yield and is considered an ideal approach for asymmetric synthesis. Despite remarkable advances in this field, enantioconvergent transformations of inert tertiary C-H bonds remain largely unexplored due to the high bond dissociation energy and the surrounding steric repulsion that pose unparalleled constraints on bond cleavage and formation. Here, we report an enantioconvergent Pd-catalyzed alkylation of racemic tertiary allylic C-H bonds of α-alkenes, providing a unique approach to access a broad range of enantioenriched γ,δ-unsaturated carbonyl compounds featuring quaternary carbon stereocenters. Mechanistic studies reveal that a stereoablative event occurs through the rate-limiting cleavage of tertiary allylic C-H bonds to generate σ-allyl-Pd species, and the achieved E/Z-selectivity of σ-allyl-Pd species effectively regulates the diastereoselectivity via a nucleophile coordination-enabled SN 2'-allylation pathway.
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Affiliation(s)
- Zhong-Sheng Nong
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Xin-Ran Chen
- Department of Chemistry, Zhejiang University, Hangzhou, 310027, China
| | - Pu-Sheng Wang
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Xin Hong
- Department of Chemistry, Zhejiang University, Hangzhou, 310027, China
| | - Liu-Zhu Gong
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
- Center for Excellence in Molecular Synthesis of Chinese Academy of Sciences, Hefei, 230026, China
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20
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Galeotti M, Lee W, Sisti S, Casciotti M, Salamone M, Houk KN, Bietti M. Radical and Cationic Pathways in C( sp3)-H Bond Oxygenation by Dioxiranes of Bicyclic and Spirocyclic Hydrocarbons Bearing Cyclopropane Moieties. J Am Chem Soc 2023; 145:24021-24034. [PMID: 37874906 PMCID: PMC10636757 DOI: 10.1021/jacs.3c07163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 10/03/2023] [Accepted: 10/04/2023] [Indexed: 10/26/2023]
Abstract
A product and DFT computational study on the reactions of 3-ethyl-3-(trifluoromethyl)dioxirane (ETFDO) with bicyclic and spirocyclic hydrocarbons bearing cyclopropyl groups was carried out. With bicyclo[n.1.0]alkanes (n = 3-6), diastereoselective formation of the alcohol product derived from C2-H bond hydroxylation was observed, accompanied by smaller amounts of products derived from oxygenation at other sites. With 1-methylbicyclo[4.1.0]heptane, rearranged products were also observed in addition to the unrearranged products deriving from oxygenation at the most activated C2-H and C5-H bonds. With spiro[2.5]octane and 6-tert-butylspiro[2.5]octane, reaction with ETFDO occurred predominantly or exclusively at the axial C4-H to give unrearranged oxygenation products, accompanied by smaller amounts of rearranged bicyclo[4.2.0]octan-1-ols. The good to outstanding site-selectivities and diastereoselectivities are paralleled by the calculated activation free energies for the corresponding reaction pathways. Computations show that the σ* orbitals of the bicyclo[n.1.0]alkane cis or trans C2-H bonds and spiro[2.5]octanes axial C4-H bond hyperconjugatively interact with the Walsh orbitals of the cyclopropane ring, activating these bonds toward HAT to ETFDO. The detection of rearranged oxygenation products in the oxidation of 1-methylbicyclo[4.1.0]heptane, spiro[2.5]octane, and 6-tert-butylspiro[2.5]octane provides unambiguous evidence for the involvement of cationic intermediates in these reactions, representing the first examples on the operation of ET pathways in dioxirane-mediated C(sp3)-H bond oxygenations. Computations support these findings, showing that formation of cationic intermediates is associated with specific stabilizing hyperconjugative interactions between the incipient carbon radical and the cyclopropane C-C bonding orbitals that trigger ET to the incipient dioxirane derived 1,1,1-trifluoro-2-hydroxy-2-butoxyl radical.
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Affiliation(s)
- Marco Galeotti
- Dipartimento
di Scienze e Tecnologie Chimiche, Università
“Tor Vergata”, Via della Ricerca Scientifica 1, I-00133, Rome, Italy
- QBIS
Research Group, Institut de Química Computacional i Catàlisi
(IQCC) and Departament de Química, Universitat de Girona, Campus Montilivi, Girona E-17071, Catalonia, Spain
| | - Woojin Lee
- Department
of Chemistry and Biochemistry, University
of California, Los Angeles, California 90095, United States
| | - Sergio Sisti
- Dipartimento
di Scienze e Tecnologie Chimiche, Università
“Tor Vergata”, Via della Ricerca Scientifica 1, I-00133, Rome, Italy
| | - Martina Casciotti
- Dipartimento
di Scienze e Tecnologie Chimiche, Università
“Tor Vergata”, Via della Ricerca Scientifica 1, I-00133, Rome, Italy
| | - Michela Salamone
- Dipartimento
di Scienze e Tecnologie Chimiche, Università
“Tor Vergata”, Via della Ricerca Scientifica 1, I-00133, Rome, Italy
| | - K. N. Houk
- Department
of Chemistry and Biochemistry, University
of California, Los Angeles, California 90095, United States
| | - Massimo Bietti
- Dipartimento
di Scienze e Tecnologie Chimiche, Università
“Tor Vergata”, Via della Ricerca Scientifica 1, I-00133, Rome, Italy
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21
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Jia Y, Zhang Z, Yu GM, Jiang X, Lu LQ, Xiao WJ. Visible Light Induced Copper-Catalyzed Enantioselective Deaminative Arylation of Amino Acid Derivatives Assisted by Phenol. Angew Chem Int Ed Engl 2023:e202312102. [PMID: 37936319 DOI: 10.1002/anie.202312102] [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: 08/18/2023] [Revised: 11/04/2023] [Accepted: 11/06/2023] [Indexed: 11/09/2023]
Abstract
The exploration of value-added conversions of naturally abundant amino acids has received considerable attention from the synthetic community. Compared with the well-established asymmetric decarboxylative transformation, the asymmetric deaminative transformation of amino acids still remains a formidable challenge, mainly due to the lack of effective strategies for the C-N bond activation and the potential incompatibility with chiral catalysts. Here, we disclose a photoinduced Cu-catalyzed asymmetric deaminative coupling reaction of amino acids with arylboronic acids. This new protocol provides a series of significant chiral phenylacetamides in generally good yields and excellent stereoselectivity under mild and green conditions (42-85 % yields, up to 97 % ee). Experimental investigations and theoretical calculations were performed to reveal the crucial role of additional phenols in improving catalytic efficiency and enantiocontrol.
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Affiliation(s)
- Yue Jia
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079, China
| | - Zhihan Zhang
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079, China
| | - Guo-Ming Yu
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079, China
| | - Xuan Jiang
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079, China
| | - Liang-Qiu Lu
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079, China
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Lanzhou, 730000, China
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan, 453007, China
| | - Wen-Jing Xiao
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079, China
- Wuhan Institute of Photochemistry and Technology, 7 North Bingang Rd., Wuhan, Hubei, 430082, China
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, 345 Lingling Road, Shanghai, 200032, China
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22
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Qian PF, Zhou T, Shi BF. Transition-metal-catalyzed atroposelective synthesis of axially chiral styrenes. Chem Commun (Camb) 2023; 59:12669-12684. [PMID: 37807950 DOI: 10.1039/d3cc03592a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Axially chiral styrenes, a type of atropisomer analogous to biaryls, have attracted great interest because of their unique presence in natural products and asymmetric catalysis. Since 2016, a number of methodologies have been developed for the atroposelective construction of these chiral skeletons, involving both transition metal catalysis and organocatalysis. In this feature article, we aim to provide a comprehensive understanding of recent advances in the asymmetric synthesis of axially chiral styrenes catalyzed by transition metals, integrating scattered work with different catalytic systems together. This feature article is cataloged into five sections according to the strategies, including asymmetric coupling, enantioselective C-H activation, central-to-axial chirality transfer, asymmetric alkyne functionalization, and atroposelective [2+2+2] cycloaddition.
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Affiliation(s)
- Pu-Fan Qian
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang 310027, China.
| | - Tao Zhou
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang 310027, China.
| | - Bing-Feng Shi
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang 310027, China.
- College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou, Henan 450001, China
- College of Material, Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou 311121, China
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, Guangdong 529020, China
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23
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Jin Y, Fan LF, Ng EWH, Yu L, Hirao H, Gong LZ. Atom Transfer Radical Coupling Enables Highly Enantioselective Carbo-Oxygenation of Alkenes with Hydrocarbons. J Am Chem Soc 2023; 145:22031-22040. [PMID: 37774121 DOI: 10.1021/jacs.3c07008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/01/2023]
Abstract
The selective functionalization of C(sp3)-H bonds has emerged as a transformative approach for streamlining synthetic routes, offering remarkable efficiency in the preparation and modification of complex organic molecules. However, the direct enantioselective transformation of hydrocarbons to medicinally valuable chiral molecules remains a significant challenge that has yet to be addressed. In this study, we adopt an atom transfer radical coupling (ATRC) strategy to achieve the asymmetric functionalization of C(sp3)-H bonds in hydrocarbons. This approach involves intermolecular H atom transfer (HAT) between a hydrocarbon and an alkoxy radical, leading to the formation of a carbon-centered radical. The resulting radical adds to alkenes, generating a new radical species that is intercepted by a chiral copper-mediated C-O bond coupling. By employing this method, we can directly access valuable chiral lactones bearing a quaternary stereocenter with high efficiency and excellent enantioselectivity. Importantly, ATRC exhibits great potential as a versatile platform for achieving stereoselective transformations of hydrocarbons.
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Affiliation(s)
- Youxiang Jin
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Lian-Feng Fan
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Elvis Wang Hei Ng
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
- Warshel Institute for Computational Biology, School of Medicine, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, China
| | - Lu Yu
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China
| | - Hajime Hirao
- Warshel Institute for Computational Biology, School of Medicine, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, China
| | - Liu-Zhu Gong
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
- Center for Excellence in Molecular Synthesis of Chinese Academy of Sciences, Hefei 230026, China
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24
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Wang R, Wang CY, Liu P, Bian KJ, Yang C, Wu BB, Wang XS. Enantioselective catalytic radical decarbonylative azidation and cyanation of aldehydes. SCIENCE ADVANCES 2023; 9:eadh5195. [PMID: 37656788 PMCID: PMC10854440 DOI: 10.1126/sciadv.adh5195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 07/31/2023] [Indexed: 09/03/2023]
Abstract
Empowered by the ubiquity of carbonyl functional groups in organic compounds, decarbonylative functionalization was prevalent in the construction of complex molecules. Under this context, asymmetric decarbonylative functionalization has emerged as an efficient pathway to accessing chiral motifs. However, ablation of enantiomeric control in a conventional 2e transition metal-catalyzed process was notable because of harsh conditions (high temperatures, etc.) that are usually required. To address this challenge and use readily accessible aldehyde directly, we report the asymmetric radical decarbonylative azidation and cyanation. Diverse aldehydes were directly used as alkyl radical precursor, engaging in the subsequent inner-sphere or outer-sphere ligand transfer where functional motifs (CN and N3) could be incorporated in excellent site- and enantioselectivity. Mild conditions, broad scope, excellent regioselectivity (driven by polarity-matching strategy), and enantioselectivity were shown for both transformations. This radical decarbonylative strategy using aldehydes as alkyl radical precursor has offered a powerful reaction manifold in asymmetric radical transformations to construct functional motifs regio- and stereoselectively.
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Affiliation(s)
- Rui Wang
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, P. R. China
| | - Cheng-Yu Wang
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, P. R. China
| | - Peng Liu
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, P. R. China
| | - Kang-Jie Bian
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, P. R. China
| | - Chi Yang
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, P. R. China
| | - Bing-Bing Wu
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, P. R. China
| | - Xi-Sheng Wang
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, P. R. China
- State Key Laboratory of Environment-friendly Energy Materials, Southwest University of Science and Technology, Mianyang 621010, P. R. China
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25
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Wang S, Yang L, Liang F, Zhong Y, Liu X, Wang Q, Zhu D. Synthetic exploration of electrophilic xanthylation via powerful N-xanthylphthalimides. Chem Sci 2023; 14:9197-9206. [PMID: 37655020 PMCID: PMC10466340 DOI: 10.1039/d3sc03194b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 07/30/2023] [Indexed: 09/02/2023] Open
Abstract
Organic xanthates are broadly applied as synthetic intermediates and bioactive molecules in synthetic chemistry. Electrophilic xanthylation represents a promising approach but has rarely been explored mainly due to the lack of powerful electrophilic reagents. Herein, synthetic exploration of electrophilic xanthylation via powerful N-xanthylphthalimides was investigated. This strategy might provide a new avenue to less-concerned but meaningful electrophilic xanthylation in organic synthesis. With the help of these powerful reagents, electrophilic xanthylation of a wide range of substrates including aryl/alkenyl boronic acids, β-keto esters, 2-oxindole, and alkyl amines, as well as previously inaccessible phenols (first report) was achieved under mild reaction conditions. Notably, this simple electrophilic xanthylation of alkyl amine substrates will occur in the desulfuration reaction, consistent with the previously reported methods. Similarly, xanthamide and thioxanthate groups could also be transformed into desired nucleophiles via this electrophilic reagent strategy. The broad substrate scope, excellent functional group compatibility and late-stage functionalization of bioactive or functional molecules made them very attractive as general reagents which will allow rapid incorporation of SC(S)R (R = OEt, Oalkyl, NEt2 and SEt) into the target molecules.
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Affiliation(s)
- Shuo Wang
- Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry & Materials Science, Northwest University Xi'an 710127 China
| | - Liuqing Yang
- Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry & Materials Science, Northwest University Xi'an 710127 China
| | - Fangcan Liang
- Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry & Materials Science, Northwest University Xi'an 710127 China
| | - Yu Zhong
- Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry & Materials Science, Northwest University Xi'an 710127 China
| | - Xueru Liu
- Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry & Materials Science, Northwest University Xi'an 710127 China
| | - Qingling Wang
- Shaanxi Natural Carbohydrate Resource Engineering Research Center, College of Food Science and Technology, Northwest University Xi'an 710069 China
| | - Dianhu Zhu
- Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry & Materials Science, Northwest University Xi'an 710127 China
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26
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Liu Y, Yan H, Chen Y, Hao E, Shi L. Photoinduced copper-catalyzed selective three-component 1,2-amino oxygenation of 1,3-dienes. Chem Commun (Camb) 2023; 59:10388-10391. [PMID: 37551551 DOI: 10.1039/d3cc02769d] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/09/2023]
Abstract
This study presents a highly effective method for the photoinduced copper-catalyzed 1,2-amino oxygenation of 1,3-dienes. This synthetic strategy involves the dual roles of a single copper catalyst, which can act as a photosensitizer to generate nitrogen radicals and can also react with allyl radicals via single electron transfer (SET) processes. The method produces a range of quaternary carbon-centered allyl carboxylic esters and tertiary ethers with high yields and excellent regioselectivity under mild reaction conditions.
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Affiliation(s)
- Yonghong Liu
- School of Chemistry, Dalian University of Technology, 116024, Dalian, China.
| | - Huaipu Yan
- School of Chemistry, Dalian University of Technology, 116024, Dalian, China.
| | - Yuqing Chen
- School of Chemistry, Dalian University of Technology, 116024, Dalian, China.
| | - Erjun Hao
- Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University, 453007, Xinxiang, China
| | - Lei Shi
- School of Chemistry, Dalian University of Technology, 116024, Dalian, China.
- Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University, 453007, Xinxiang, China
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27
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Wang Q, Wu S, Zou J, Liang X, Mou C, Zheng P, Chi YR. NHC-catalyzed enantioselective access to β-cyano carboxylic esters via in situ substrate alternation and release. Nat Commun 2023; 14:4878. [PMID: 37573355 PMCID: PMC10423276 DOI: 10.1038/s41467-023-40645-8] [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: 04/03/2023] [Accepted: 08/04/2023] [Indexed: 08/14/2023] Open
Abstract
A carbene-catalyzed asymmetric access to chiral β-cyano carboxylic esters is disclosed. The reaction proceeds between β,β-disubstituted enals and aromatic thiols involving enantioselective protonation of enal β-carbon. Two main factors contribute to the success of this reaction. One involves in situ ultrafast addition of the aromatic thiol substrates to the carbon-carbon double bond of the enal substrate. This reaction converts almost all enal substrate to a Thiol-click Intermediate, significantly reducing aromatic thiol substrates concentration and suppressing the homo-coupling reaction of enals. Another factor is an in situ release of enal substrate from the Thiol-click Intermediate for the desired reaction to proceed effectively. The optically enriched β-cyano carboxylic esters from our method can be readily transformed to medicines that include γ-aminobutyric acids derivatives such as Rolipram. In addition to synthetic utilities, our control of reaction outcomes via in situ substrate modulation and release can likely inspire future reaction development.
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Affiliation(s)
- Qingyun Wang
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang, 550025, China
| | - Shuquan Wu
- Center for Industrial Catalysis and Cleaning Process Development, School of Chemical Engineering, Guizhou Minzu University, Guiyang, 550025, China
| | - Juan Zou
- School of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang, 550025, China
| | - Xuyang Liang
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang, 550025, China
| | - Chengli Mou
- School of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang, 550025, China
| | - Pengcheng Zheng
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang, 550025, China.
| | - Yonggui Robin Chi
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang, 550025, China.
- School of Chemistry, Chemical Engineering, and Biotechnology, Nanyang Technological University, Singapore, 637371, Singapore.
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28
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Lepori M, Schmid S, Barham JP. Photoredox catalysis harvesting multiple photon or electrochemical energies. Beilstein J Org Chem 2023; 19:1055-1145. [PMID: 37533877 PMCID: PMC10390843 DOI: 10.3762/bjoc.19.81] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 07/07/2023] [Indexed: 08/04/2023] Open
Abstract
Photoredox catalysis (PRC) is a cutting-edge frontier for single electron-transfer (SET) reactions, enabling the generation of reactive intermediates for both oxidative and reductive processes via photon activation of a catalyst. Although this represents a significant step towards chemoselective and, more generally, sustainable chemistry, its efficacy is limited by the energy of visible light photons. Nowadays, excellent alternative conditions are available to overcome these limitations, harvesting two different but correlated concepts: the use of multi-photon processes such as consecutive photoinduced electron transfer (conPET) and the combination of photo- and electrochemistry in synthetic photoelectrochemistry (PEC). Herein, we review the most recent contributions to these fields in both oxidative and reductive activations of organic functional groups. New opportunities for organic chemists are captured, such as selective reactions employing super-oxidants and super-reductants to engage unactivated chemical feedstocks, and scalability up to gram scales in continuous flow. This review provides comparisons between the two techniques (multi-photon photoredox catalysis and PEC) to help the reader to fully understand their similarities, differences and potential applications and to therefore choose which method is the most appropriate for a given reaction, scale and purpose of a project.
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Affiliation(s)
- Mattia Lepori
- Fakultät für Chemie und Pharmazie, Universität Regensburg, Universitatsstraße 31, 93040 Regensburg, Germany
| | - Simon Schmid
- Fakultät für Chemie und Pharmazie, Universität Regensburg, Universitatsstraße 31, 93040 Regensburg, Germany
| | - Joshua P Barham
- Fakultät für Chemie und Pharmazie, Universität Regensburg, Universitatsstraße 31, 93040 Regensburg, Germany
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29
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Du Z, Liu S, Li Y, Peng J, Sun Y, Song Y, Liu Y, Zeng X. Fluoroamide-Directed Regiodivergent C-Alkylation of Nitroalkanes. Org Lett 2023. [PMID: 37314942 DOI: 10.1021/acs.orglett.3c01297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Herein, by exploiting different activation modes of fluoroamides, we achieved α- and δ-C(sp3)-H alkylation of nitroalkanes with switchable regioselectivity. Cu catalysis enabled the interception of a distal C-centered radical by a N-centered radical to couple nitroalkanes and unactivated δ-C-H bonds. In addition, imines generated in situ by fluoroamides were trapped by nitroalkanes to realize the α-C-H alkylation of amides. Both of those scalable protocols have broad substrate scopes and good functional group tolerance.
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Affiliation(s)
- Zhibin Du
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, China
| | - Shiwen Liu
- College of Textiles and Clothing, Institute of Flexible Functional Materials, Yancheng Institute of Technology, Yancheng, Jiangsu 224000, China
| | - Yuke Li
- School of Pharmacy, Nanchang University, Nanchang, Jiangxi 330031, China
| | - Junjie Peng
- School of Pharmacy, Nanchang University, Nanchang, Jiangxi 330031, China
| | - Yanji Sun
- School of Pharmacy, Nanchang University, Nanchang, Jiangxi 330031, China
| | - Yanshan Song
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, China
| | - Yuxuan Liu
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, China
| | - Xiaojun Zeng
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, China
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30
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Fu L, Chen X, Fan W, Chen P, Liu G. Copper-Catalyzed Asymmetric Functionalization of Vinyl Radicals for the Access to Vinylarene Atropisomers. J Am Chem Soc 2023. [PMID: 37300506 DOI: 10.1021/jacs.3c04498] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A novel asymmetric radical strategy for the straightforward synthesis of atropisomerically chiral vinyl arenes has been established herein, proceeding through copper-catalyzed atroposelective cyanation/azidation of aryl-substituted vinyl radicals. Critical to the success of the radical relay process is the atroposelective capture of the highly reactive vinyl radicals with chiral L*Cu(II) cyanide or azide species. Moreover, these axially chiral vinylarene products can be easily transformed into atropisomerically enriched amides and amines, enantiomerically enriched benzyl nitriles via an axis-to-center chirality transfer process, and an atropisomerically pure organocatalyst for the chemo-, diastereo-, and enantioselective (4 + 2) cyclization reaction.
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Affiliation(s)
- Liang Fu
- Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241002, China
- State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Xin Chen
- Chang-Kung Chuang Institute, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China
| | - Wenzheng Fan
- State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Pinhong Chen
- State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Guosheng Liu
- Chang-Kung Chuang Institute, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China
- State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
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31
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Qi R, Chen Q, Liu L, Ma Z, Pan D, Wang H, Li Z, Wang C, Xu Z. Copper-catalyzed asymmetric C(sp 3)-H cyanoalkylation of glycine derivatives and peptides. Nat Commun 2023; 14:3295. [PMID: 37280209 DOI: 10.1038/s41467-023-38871-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 05/16/2023] [Indexed: 06/08/2023] Open
Abstract
Alkylnitriles play important roles in many fields because of their unique electronic properties and structural characteristics. Incorporating cyanoalkyl with characteristic spectroscopy and reactivity properties into amino acids and peptides is of special interest for potential imaging and therapeutic purposes. Here, we report a copper-catalyzed asymmetric cyanoalkylation of C(sp3)-H. In the reactions, glycine derivatives can effectively couple with various cycloalkanone oxime esters with high enantioselectivities, and the reaction can be applied to the late-stage modification of peptides with good yields and excellent stereoselectivities, which is useful for modern peptide synthesis and drug discovery. The mechanistic studies show that the in situ formed copper complex by the coordination of glycine derivatives and chiral phosphine Cu catalyst can not only mediate the single electronic reduction of cycloalkanone oxime ester but also control the stereoselectivity of the cyanoalkylation reaction.
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Affiliation(s)
- Rupeng Qi
- School of Pharmacy, Lanzhou University, 730000, Lanzhou, China
- Research Unit of Peptide Science, Chinese Academy of Medical Sciences, 2019RU066, 730000, Lanzhou, China
| | - Qiao Chen
- School of Pharmacy, Lanzhou University, 730000, Lanzhou, China
| | - Liangyu Liu
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, 730000, Lanzhou, China
| | - Zijian Ma
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, 730000, Lanzhou, China
| | - Da Pan
- School of Pharmacy, Lanzhou University, 730000, Lanzhou, China
| | - Hongying Wang
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, 730000, Lanzhou, China
| | - Zhixuan Li
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, 730000, Lanzhou, China
| | - Chao Wang
- Research Unit of Peptide Science, Chinese Academy of Medical Sciences, 2019RU066, 730000, Lanzhou, China.
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, 730000, Lanzhou, China.
| | - Zhaoqing Xu
- Research Unit of Peptide Science, Chinese Academy of Medical Sciences, 2019RU066, 730000, Lanzhou, China.
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, 730000, Lanzhou, China.
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32
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Li MY, Zhai S, Nong XM, Gu A, Li J, Lin GQ, Liu Y. Trisubstituted alkenes featuring aryl groups: stereoselective synthetic strategies and applications. Sci China Chem 2023; 66:1261-1287. [DOI: 10.1007/s11426-022-1515-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 01/17/2023] [Indexed: 03/07/2024]
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33
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Li Z, Zhang G, Song Y, Li M, Li Z, Ding W, Wu J. Copper-Catalyzed Enantioselective Decarboxylative Cyanation of Benzylic Acids Promoted by Hypervalent Iodine(III) Reagents. Org Lett 2023; 25:3023-3028. [PMID: 37129410 DOI: 10.1021/acs.orglett.3c00816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Copper-catalyzed asymmetric radical cyanation reactions have emerged as a powerful strategy for rapid construction of α-chiral nitriles. However, the directly decarboxylative cyanation reactions of common alkyl carboxylic acids remain largely elusive. Herein, we report a protocol for copper-catalyzed direct and enantioselective decarboxylative cyanation of benzylic acids. The in situ activation of acid substrates by a commercially inexpensive hypervalent iodine(III) reagent promoted the yield of the alkyl radicals under mild reaction conditions without prefunctionalization. The structurally diverse chiral alkyl nitriles were produced in good yields with high enantioselectivities. In addition, the chiral products can be readily converted to other useful chiral compounds via further transformations.
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Affiliation(s)
- Zhaoxia Li
- Henan Institute of Advanced Technology, College of Chemistry, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Guang'an Zhang
- Henan Institute of Advanced Technology, College of Chemistry, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Yue Song
- High & New Technology Research Center, Henan Academy of Sciences, Zhengzhou 450002, P. R. China
| | - Miaomiao Li
- Henan Institute of Advanced Technology, College of Chemistry, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Zhongxian Li
- High & New Technology Research Center, Henan Academy of Sciences, Zhengzhou 450002, P. R. China
| | - Wei Ding
- Henan Institute of Advanced Technology, College of Chemistry, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Junliang Wu
- Henan Institute of Advanced Technology, College of Chemistry, Zhengzhou University, Zhengzhou 450001, P. R. China
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34
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Drennhaus T, Leifert D, Lammert J, Drennhaus JP, Bergander K, Daniliuc CG, Studer A. Enantioselective Copper-Catalyzed Fukuyama Indole Synthesis from 2-Vinylphenyl Isocyanides. J Am Chem Soc 2023; 145:8665-8676. [PMID: 37029692 DOI: 10.1021/jacs.3c01667] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2023]
Abstract
Enantioenriched chiral indoles are of high interest for the pharmaceutical and agrochemical industries. Herein, we present an asymmetric Fukuyama indole synthesis through a mild and efficient radical cascade reaction to access 2-fluoroalkylated 3-(α-cyanobenzylated) indoles by stereochemical control with a chiral copper-bisoxazoline complex using 2-vinylphenyl arylisocyanides as radical acceptors and fluoroalkyl iodides as C-radical precursors. Radical addition to the isonitrile moiety, 5-exo-trig cyclization, and Cu-catalyzed stereoselective cyanation provide the targeted indoles with excellent enantioselectivity and good yields. Due to the similar electronic and steric properties of the two aryl substituents to be differentiated, the enantioselective construction of the cyano diaryl methane stereocenter is highly challenging. Mechanistic studies reveal a negative nonlinear effect which allows proposing a model to explain the stereochemical outcome. Scalability and potential utility of the enantioenriched 3-(α-cyanobenzylated) indoles as hubs for chiral tryptamines, indole-3-acetic acid derivatives, and triarylmethanes are demonstrated, and a formal synthesis of a natural product analogue is disclosed.
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Affiliation(s)
- Till Drennhaus
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, 48149 Münster, Germany
| | - Dirk Leifert
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, 48149 Münster, Germany
| | - Jessika Lammert
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, 48149 Münster, Germany
| | | | - Klaus Bergander
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, 48149 Münster, Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, 48149 Münster, Germany
| | - Armido Studer
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, 48149 Münster, Germany
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35
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Xu P, Xie J, Wang DS, Zhang XP. Metalloradical approach for concurrent control in intermolecular radical allylic C-H amination. Nat Chem 2023; 15:498-507. [PMID: 36635599 PMCID: PMC10073309 DOI: 10.1038/s41557-022-01119-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 11/28/2022] [Indexed: 01/13/2023]
Abstract
Although they offer great potentials, the high reactivity and diverse pathways of radical chemistry pose difficult problems for applications in organic synthesis. In addition to the differentiation of multiple competing pathways, the control of various selectivities in radical reactions presents both formidable challenges and great opportunities. To regulate chemoselectivity and regioselectivity, as well as diastereoselectivity and enantioselectivity, calls for the formulation of conceptually new approaches and fundamentally different governing principles. Here we show that Co(II)-based metalloradical catalysis enables the radical chemoselective intermolecular amination of allylic C-H bonds through the employment of modularly designed D2-symmetric chiral amidoporphyrins with a tunable pocket-like environment as the supporting ligand. The reaction exhibits a remarkable convergence of regioselectivity, diastereoselectivity and enantioselectivity in a single catalytic operation. In addition to demonstrating the unique opportunities of metalloradical catalysis in controlling homolytic radical reactions, the Co(II)-catalysed convergent C-H amination offers a route to synthesize valuable chiral α-tertiary amines directly from an isomeric mixture of alkenes.
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Affiliation(s)
- Pan Xu
- Department of Chemistry, Merkert Chemistry Center, Boston College, Boston, MA, USA
| | - Jingjing Xie
- Department of Chemistry, Merkert Chemistry Center, Boston College, Boston, MA, USA
| | - Duo-Sheng Wang
- Department of Chemistry, Merkert Chemistry Center, Boston College, Boston, MA, USA
| | - X Peter Zhang
- Department of Chemistry, Merkert Chemistry Center, Boston College, Boston, MA, USA.
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36
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Ren H, Zhang P, Xu J, Ma W, Tu D, Lu CS, Yan H. Direct B-H Functionalization of Icosahedral Carboranes via Hydrogen Atom Transfer. J Am Chem Soc 2023; 145:7638-7647. [PMID: 36946888 DOI: 10.1021/jacs.3c01314] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
The efficient and selective functionalization of icosahedral carboranes (C2B10H12) at the boron vertexes is a long-standing challenge owing to the presence of 10 inert B-H bonds in a similar chemical environment. Herein, we report a new reaction paradigm for direct B-H functionalization of icosahedral carboranes via B-H homolysis enabled by a nitrogen-centered radical-mediated hydrogen atom transfer (HAT) strategy. Both the HAT process of the carborane B-H bond and the resulting boron-centered carboranyl radical intermediate have been confirmed experimentally. The reaction occurs at the most electron-rich boron vertex with the lowest B-H bond dissociation energy (BDE). Using this strategy, diverse carborane derivatization, including thiolation, selenation, alkynylation, alkenylation, cyanation, and halogenation, have been achieved in satisfactory yields under a photoinitiated condition in a metal-free and redox-neutral fashion. Moreover, the synthetic utility of the current protocol was also demonstrated by both the scale-up reaction and the construction of carborane-based functional molecules. Therefore, this methodology opens a radical pathway to carborane functionalization, which is distinct from the B-H heterolytic mechanism in the traditional strategies.
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Affiliation(s)
- Hongyuan Ren
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Ping Zhang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Jingkai Xu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Wenli Ma
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Deshuang Tu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Chang-Sheng Lu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Hong Yan
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
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37
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You CM, Huang C, Tang S, Xiao P, Wang S, Wei Z, Lei A, Cai H. N-Allylation of Azoles with Hydrogen Evolution Enabled by Visible-Light Photocatalysis. Org Lett 2023; 25:1722-1726. [PMID: 36869877 DOI: 10.1021/acs.orglett.3c00399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/05/2023]
Abstract
Direct N-allylation of azoles with hydrogen evolution has been achieved through the synergistic combination of organic photocatalysis and cobalt catalysis. The protocol bypasses stoichiometric oxidants and prefunctionalization of alkenes and produces hydrogen (H2) as the byproduct. This transformation highlights high step- and atom-economy, high efficiency, and broad functional group tolerance for further derivatization, which opens a door for C-N bond formation that is valuable in heterocyclic chemistry.
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Affiliation(s)
- Chang-Ming You
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, P. R. China
| | - Cheng Huang
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, P. R. China
| | - Sheng Tang
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, P. R. China
| | - Peng Xiao
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, P. R. China
| | - Shengchun Wang
- College of Chemistry and Molecular Sciences, Institute for Advanced Studies (IAS), Wuhan University, Wuhan, Hubei 430072, P. R. China
| | - Zhenhong Wei
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, P. R. China
| | - Aiwen Lei
- College of Chemistry and Molecular Sciences, Institute for Advanced Studies (IAS), Wuhan University, Wuhan, Hubei 430072, P. R. China
| | - Hu Cai
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, P. R. China
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38
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Xu S, Ping Y, Li W, Guo H, Su Y, Li Z, Wang M, Kong W. Enantioselective C(sp 3)-H Functionalization of Oxacycles via Photo-HAT/Nickel Dual Catalysis. J Am Chem Soc 2023; 145:5231-5241. [PMID: 36812098 DOI: 10.1021/jacs.2c12481] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
The selective functionalization of ubiquitous but inert C-H bonds is highly appealing in synthetic chemistry, but the direct transformation of hydrocarbons lacking directing groups into high-value chiral molecules remains a formidable challenge. Herein, we develop an enantioselective C(sp3)-H functionalization of undirected oxacycles via photo-HAT/nickel dual catalysis. This protocol provides a practical platform for the rapid construction of high-value and enantiomerically enriched oxacycles directly from simple and abundant hydrocarbon feedstocks. The synthetic utility of this strategy is further demonstrated in the late-stage functionalization of natural products and the synthesis of many pharmaceutically relevant molecules. Experimental and density functional theory calculation studies provide detailed insights into the mechanism and the origin of enantioselectivity for the asymmetric C(sp3)-H functionalization.
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Affiliation(s)
- Sheng Xu
- The Institute for Advanced Studies and Hongyi Honor College, Wuhan University, Wuhan 430072, China
| | - Yuanyuan Ping
- The Institute for Advanced Studies and Hongyi Honor College, Wuhan University, Wuhan 430072, China
| | - Wei Li
- The Institute for Advanced Studies and Hongyi Honor College, Wuhan University, Wuhan 430072, China
| | - Haoyun Guo
- The Institute for Advanced Studies and Hongyi Honor College, Wuhan University, Wuhan 430072, China
| | - Yinyan Su
- The Institute for Advanced Studies and Hongyi Honor College, Wuhan University, Wuhan 430072, China
| | - Ziyang Li
- The Institute for Advanced Studies and Hongyi Honor College, Wuhan University, Wuhan 430072, China
| | - Minyan Wang
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Wangqing Kong
- The Institute for Advanced Studies and Hongyi Honor College, Wuhan University, Wuhan 430072, China
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39
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Bower JK, Reese MS, Mazin IM, Zarnitsa LM, Cypcar AD, Moore CE, Sokolov AY, Zhang S. C(sp 3)-H cyanation by a formal copper(iii) cyanide complex. Chem Sci 2023; 14:1301-1307. [PMID: 36756315 PMCID: PMC9891353 DOI: 10.1039/d2sc06573h] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 01/05/2023] [Indexed: 01/18/2023] Open
Abstract
High-valent metal oxo complexes are prototypical intermediates for the activation and hydroxylation of alkyl C-H bonds. Substituting the oxo ligand with other functional groups offers the opportunity for additional C-H functionalization beyond C-O bond formation. However, few species aside from metal oxo complexes have been reported to both activate and functionalize alkyl C-H bonds. We herein report the first example of an isolated copper(iii) cyanide complex (LCuIIICN) and its C-H cyanation reactivity. We found that the redox potential (E ox) of substrates, instead of C-H bond dissociation energy, is a key determinant of the rate of PCET, suggesting an oxidative asynchronous CPET or ETPT mechanism. Among substrates with the same BDEs, those with low redox potentials transfer H atoms up to a million-fold faster. Capitalizing on this mechanistic insight, we found that LCuIIICN is highly selective for cyanation of amines, which is predisposed to oxidative asynchronous or stepwise transfer of H+/e-. Our study demonstrates that the asynchronous effect of PCET is an appealing tool for controlling the selectivity of C-H functionalization.
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Affiliation(s)
- Jamey K. Bower
- Department of Chemistry and Biochemistry, The Ohio State University100 W. 18 AveColumbusOH43210USA
| | - Maxwell S. Reese
- Department of Chemistry and Biochemistry, The Ohio State University100 W. 18 AveColumbusOH43210USA
| | - Ilia M. Mazin
- Department of Chemistry and Biochemistry, The Ohio State University100 W. 18 AveColumbusOH43210USA
| | - Lina M. Zarnitsa
- Department of Chemistry and Biochemistry, The Ohio State University100 W. 18 AveColumbusOH43210USA
| | - Andrew D. Cypcar
- Department of Chemistry and Biochemistry, The Ohio State University100 W. 18 AveColumbusOH43210USA
| | - Curtis E. Moore
- Department of Chemistry and Biochemistry, The Ohio State University100 W. 18 AveColumbusOH43210USA
| | - Alexander Yu. Sokolov
- Department of Chemistry and Biochemistry, The Ohio State University100 W. 18 AveColumbusOH43210USA
| | - Shiyu Zhang
- Department of Chemistry and Biochemistry, The Ohio State University 100 W. 18th Ave Columbus OH 43210 USA
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40
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Ma X, Li L, Tan M, Zhong Z, Liang J, Li P, Song Q. Modular assembly of versatile tetrasubstituted alkenyl monohalides from alkynyl tetracoordinate borons. Chem 2023. [DOI: 10.1016/j.chempr.2023.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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41
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Yuan Y, Yang J, Zhang J. Cu-catalyzed enantioselective decarboxylative cyanation via the synergistic merger of photocatalysis and electrochemistry. Chem Sci 2023; 14:705-710. [PMID: 36741520 PMCID: PMC9847662 DOI: 10.1039/d2sc05428k] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 12/06/2022] [Indexed: 12/12/2022] Open
Abstract
The development of an efficient and straightforward method for decarboxylative coupling using common alkyl carboxylic acid is of great value. However, decarboxylative coupling with nucleophiles always needs stoichiometric chemical oxidants or substrate prefunctionalization. Herein, we report a protocol for Cu-catalyzed enantioselective decarboxylative cyanation via the merger of photocatalysis and electrochemistry. CeCl3 and Cu/BOX were used as co-catalysts to promote the decarboxylation and cyanation, and both catalysts were regenerated via anodic oxidation. This method establishes a proof of concept enantioselective transformation via photoelectrocatalysis. Studies by DFT calculations provided mechanistic insight on enantioselectivity control.
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Affiliation(s)
- Yin Yuan
- Department of Chemistry, Fudan University2005 Songhu RoadShanghai200438P. R. China
| | - Junfeng Yang
- Department of Chemistry, Fudan University2005 Songhu RoadShanghai200438P. R. China,Fudan Zhangjiang InstituteShanghai 201203P. R. China
| | - Junliang Zhang
- Department of Chemistry, Fudan University2005 Songhu RoadShanghai200438P. R. China
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42
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Ding D, Fan LF, Han ZY, Wang PS. Redox-Neutral 1,4-Dicarbonfunctionalization of 1,3-Butadiene by Merging Photoredox and Nickel Catalysis. Org Lett 2023; 25:210-214. [PMID: 36534618 DOI: 10.1021/acs.orglett.2c04060] [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
The diverse functionalization of 1,3-butadiene provides wide applicability toward the synthesis of abundant and useful allylic compounds. Here, we describe a three-component and redox-neutral assembly of readily available C═X compounds, 1,3-butadiene, and various nucleophiles by merging photoredox and nickel catalysis, enabling the rapid synthesis of structurally diverse homoallyl amines and homoallylic alcohols.
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Affiliation(s)
- Du Ding
- Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Lian-Feng Fan
- Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Zhi-Yong Han
- Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Pu-Sheng Wang
- Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
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43
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Yang K, Wang Y, Luo S, Fu N. Electrophotochemical Metal-Catalyzed Enantioselective Decarboxylative Cyanation. Chemistry 2023; 29:e202203962. [PMID: 36638008 DOI: 10.1002/chem.202203962] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/13/2023] [Accepted: 01/13/2023] [Indexed: 01/14/2023]
Abstract
In contrast to the rapid growth of electrophotocatalysis in recent years, enantioselective catalytic reactions powered by this unique methodology remain rare. In this work, we report an electrophotochemical metal-catalyzed protocol for direct asymmetric decarboxylative cyanation of aliphatic carboxylic acids. The synergistic merging of electrophotochemical cerium catalysis and asymmetric electrochemical copper catalysis permits mild reaction conditions for the formation and utilization of the key carbon centered radicals by combining the power of light and electrical energy. Electrophotochemical cerium catalysis enables radical decarboxylation to produce alkyl radicals, which could be effectively intercepted by asymmetric electrochemical copper catalysis for the construction of C-CN bonds in a highly stereoselective fashion. This environmentally benign method smoothly converts a diverse array of arylacetic acids into the corresponding alkyl nitriles in good yields and enantioselectivities without using chemical oxidants or pre-functionalization of the acid substrates and can be readily scaled up.
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Affiliation(s)
- Kai Yang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, P. R. China
- Center of Basic Molecular Science, Department of Chemistry, Tsinghua University, 100084, Beijing, P. R. China
| | - Yukang Wang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, P. R. China
- University of Chinese Academy of Sciences, 100049, Beijing, P. R. China
| | - Sanzhong Luo
- Center of Basic Molecular Science, Department of Chemistry, Tsinghua University, 100084, Beijing, P. R. China
| | - Niankai Fu
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, P. R. China
- University of Chinese Academy of Sciences, 100049, Beijing, P. R. China
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44
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Wang L, Sun J, Xia J, Ma R, Zheng G, Zhang Q. Visible light-mediated NHC and photoredox co-catalyzed 1,2-sulfonylacylation of allenes via acyl and allyl radical cross-coupling. Org Chem Front 2023. [DOI: 10.1039/d2qo01993k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Visible light-mediated NHC and photoredox co-catalyzed radical 1,2-sulfonylacylation of allenes via cross-coupling between an allyl radical and an NHC-stabilized acyl radical.
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Affiliation(s)
- Lihong Wang
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Department of ChemistryNortheast Normal University, Changchun 130024, China
| | - Jiaqiong Sun
- School of Environment, Northeast Normal University, Changchun 130117, China
| | - Jiuli Xia
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Department of ChemistryNortheast Normal University, Changchun 130024, China
| | - Ruiyang Ma
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Department of ChemistryNortheast Normal University, Changchun 130024, China
| | - Guangfan Zheng
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Department of ChemistryNortheast Normal University, Changchun 130024, China
| | - Qian Zhang
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Department of ChemistryNortheast Normal University, Changchun 130024, China
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
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45
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Yan F, Bai JF, Dong Y, Liu S, Li C, Du CX, Li Y. Catalytic Cyanation of C-N Bonds with CO 2/NH 3. JACS AU 2022; 2:2522-2528. [PMID: 36465537 PMCID: PMC9709945 DOI: 10.1021/jacsau.2c00392] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 10/04/2022] [Accepted: 10/04/2022] [Indexed: 06/17/2023]
Abstract
Cyanation of benzylic C-N bonds is useful in the preparation of important α-aryl nitriles. The first general catalytic cyanation of α-(hetero)aryl amines, analogous to the Sandmeyer reaction of anilines, was developed using reductive cyanation with CO2/NH3. A broad array of α-aryl nitriles was obtained in high yields and regioselectivity by C-N cleavage of intermediates as ammonium salts. Good tolerance of functional groups such as ethers, CF3, F, Cl, esters, indoles, and benzothiophenes was achieved. Using 13CO2, a 13C-labeled tryptamine homologue (five steps, 31% yield) and Cysmethynil (six steps, 37% yield) were synthesized. Both electronic and steric effects of ligands influence the reactivity of alkyl nickel species with electrophilic silyl isocyanates and thus determine the reactivity and selectivity of the cyanation reaction. This work contributes to the understanding of the controllable activation of CO2/NH3 and provides the promising potential of the amine cyanation reaction in the synthesis of bio-relevant molecules.
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Affiliation(s)
- Fachao Yan
- State
Key Laboratory for Oxo Synthesis and Selective Oxidation, Suzhou Research
Institute of LICP, Center for Excellence in Molecular Synthesis, Lanzhou Institute of Chemical Physics (LICP), Chinese
Academy of Sciences, Lanzhou 730000, P. R. China
- University
of Chinese Academy of Sciences, Beijing 100049, P. R.
China
| | - Jian-Fei Bai
- State
Key Laboratory for Oxo Synthesis and Selective Oxidation, Suzhou Research
Institute of LICP, Center for Excellence in Molecular Synthesis, Lanzhou Institute of Chemical Physics (LICP), Chinese
Academy of Sciences, Lanzhou 730000, P. R. China
| | - Yanan Dong
- State
Key Laboratory for Oxo Synthesis and Selective Oxidation, Suzhou Research
Institute of LICP, Center for Excellence in Molecular Synthesis, Lanzhou Institute of Chemical Physics (LICP), Chinese
Academy of Sciences, Lanzhou 730000, P. R. China
| | - Shaoli Liu
- College
of Chemistry and Chemical Engineering, Yantai
University, Yantai 264005, P. R. China
| | - Chen Li
- State
Key Laboratory for Oxo Synthesis and Selective Oxidation, Suzhou Research
Institute of LICP, Center for Excellence in Molecular Synthesis, Lanzhou Institute of Chemical Physics (LICP), Chinese
Academy of Sciences, Lanzhou 730000, P. R. China
| | - Chen-Xia Du
- College
of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Yuehui Li
- State
Key Laboratory for Oxo Synthesis and Selective Oxidation, Suzhou Research
Institute of LICP, Center for Excellence in Molecular Synthesis, Lanzhou Institute of Chemical Physics (LICP), Chinese
Academy of Sciences, Lanzhou 730000, P. R. China
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46
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Fan W, Zhao X, Deng Y, Chen P, Wang F, Liu G. Electrophotocatalytic Decoupled Radical Relay Enables Highly Efficient and Enantioselective Benzylic C–H Functionalization. J Am Chem Soc 2022; 144:21674-21682. [DOI: 10.1021/jacs.2c09366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Wenzheng Fan
- State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Xueyao Zhao
- State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Yunshun Deng
- Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Pinhong Chen
- State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Fei Wang
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Guosheng Liu
- State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
- Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
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47
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Radical addition-triggered remote functionalization of C–H bond via 1, n-hydrogen atom transfer process. Tetrahedron 2022. [DOI: 10.1016/j.tet.2022.133172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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48
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Lai XL, Chen M, Wang Y, Song J, Xu HC. Photoelectrochemical Asymmetric Catalysis Enables Direct and Enantioselective Decarboxylative Cyanation. J Am Chem Soc 2022; 144:20201-20206. [DOI: 10.1021/jacs.2c09050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Xiao-Li Lai
- 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, PR China
| | - Ming Chen
- 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, PR China
| | - Yuqi Wang
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, PR China
| | - Jinshuai Song
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, PR China
| | - Hai-Chao 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, PR China
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49
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Photoelectrochemical asymmetric catalysis enables site- and enantioselective cyanation of benzylic C–H bonds. Nat Catal 2022. [DOI: 10.1038/s41929-022-00855-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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50
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Ma S, Wang S, Cao J, Liu F. Rapid and Accurate Estimation of Activation Free Energy in Hydrogen Atom Transfer-Based C-H Activation Reactions: From Empirical Model to Artificial Neural Networks. ACS OMEGA 2022; 7:34858-34867. [PMID: 36211072 PMCID: PMC9535641 DOI: 10.1021/acsomega.2c03252] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 09/07/2022] [Indexed: 06/16/2023]
Abstract
A well-performing machine learning (ML) model is obtained by using proper descriptors and artificial neural network (ANN) algorithms, which can quickly and accurately predict activation free energy in hydrogen atom transfer (HAT)-based sp3 C-H activation. Density functional theory calculations (UωB97X-D) are used to establish the reaction system data sets of methoxyl (CH3O·), trifluoroethoxyl (CF3CH2O·), tert-butoxyl (tBuO·), and cumyloxyl (CumO·) radicals. The simplified Roberts' equation proposed in our recent study works here [R 2 = 0.84, mean absolute error (MAE) = 0.85 kcal/mol]. Its performance is comparable with univariate Mulliken-type electronegativity (χ) with the ANN model. The ANN model with bond dissociation free energy, χ, α-unsaturation, and Nolan buried volume (%V buried) successively improves R 2 and MAE to 0.93 and 0.54 kcal/mol, respectively. It reproduces the test sets of trichloroethoxyl (CCl3CH2O·) with R 2 = 0.87 and MAE = 0.89 kcal/mol and accurately predicts the relative experimental barrier of the HAT reactions with CumO· and the site selectivity of CH3O·.
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Affiliation(s)
- Siqi Ma
- School
of Chemistry and Chemical Engineering, Shanghai
University of Engineering Science, Shanghai 201620, China
| | - Shipeng Wang
- School
of Chemistry and Chemical Engineering, Shanghai
University of Engineering Science, Shanghai 201620, China
| | - Jiawei Cao
- School
of Chemistry and Chemical Engineering, Shanghai
University of Engineering Science, Shanghai 201620, China
| | - Fengjiao Liu
- School
of Chemistry and Chemical Engineering, Shanghai
University of Engineering Science, Shanghai 201620, China
- Department
of Chemistry and Biochemistry, University
of California, Los Angeles, California 90095, United States
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