1
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Wojdyla Z, Srnec M. Radical ligand transfer: mechanism and reactivity governed by three-component thermodynamics. Chem Sci 2024; 15:8459-8471. [PMID: 38846394 PMCID: PMC11151871 DOI: 10.1039/d4sc01507j] [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: 03/04/2024] [Accepted: 04/19/2024] [Indexed: 06/09/2024] Open
Abstract
Here, we demonstrate that the relationship between reactivity and thermodynamics in radical ligand transfer chemistry can be understood if this chemistry is dissected as concerted ion-electron transfer (cIET). Namely, we investigate radical ligand transfer reactions from the perspective of thermodynamic contributions to the reaction barrier: the diagonal effect of the free energy of the reaction, and the off-diagonal effect resulting from asynchronicity and frustration, which we originally derived from the thermodynamic cycle for concerted proton-electron transfer (cPET). This study on the OH transfer reaction shows that the three-component thermodynamic model goes beyond cPET chemistry, successfully capturing the changes in radical ligand transfer reactivity in a series of model FeIII-OH⋯(diflouro)cyclohexadienyl systems. We also reveal the decisive role of the off-diagonal thermodynamics in determining the reaction mechanism. Two possible OH transfer mechanisms, in which electron transfer is coupled with either OH- and OH+ transfer, are associated with two competing thermodynamic cycles. Consequently, the operative mechanism is dictated by the cycle yielding a more favorable off-diagonal effect on the barrier. In line with this thermodynamic link to the mechanism, the transferred OH group in OH-/electron transfer retains its anionic character and slightly changes its volume in going from the reactant to the transition state. In contrast, OH+/electron transfer develops an electron deficiency on OH, which is evidenced by an increase in charge and a simultaneous decrease in volume. In addition, the observations in the study suggest that an OH+/electron transfer reaction can be classified as an adiabatic radical transfer, and the OH-/electron transfer reaction as a less adiabatic ion-coupled electron transfer.
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Affiliation(s)
- Zuzanna Wojdyla
- J. Heyrovský Institute of Physical Chemistry, The Czech Academy of Sciences Dolejškova 3 Prague 8 18223 Czech Republic
| | - Martin Srnec
- J. Heyrovský Institute of Physical Chemistry, The Czech Academy of Sciences Dolejškova 3 Prague 8 18223 Czech Republic
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2
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Ghosal S, Das A, Roy D, Dasgupta J. Tuning light-driven oxidation of styrene inside water-soluble nanocages. Nat Commun 2024; 15:1810. [PMID: 38418497 PMCID: PMC10902312 DOI: 10.1038/s41467-024-45991-9] [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: 06/27/2022] [Accepted: 02/08/2024] [Indexed: 03/01/2024] Open
Abstract
Selective functionalization of innate sp2 C-H bonds under ambient conditions is a grand synthetic challenge in organic chemistry. Here we combine host-guest charge transfer-based photoredox chemistry with supramolecular nano-confinement to achieve selective carbonylation of styrene by tuning the dioxygen concentration. We observe exclusive photocatalytic formation of benzaldehyde under excess O2 (>1 atm) while Markovnikov addition of water produced acetophenone in deoxygenated condition upon photoexcitation of confined styrene molecules inside a water-soluble cationic nanocage. Further by careful tuning of the nanocage size, electronics, and guest preorganization, we demonstrate rate enhancement of benzaldehyde formation and a complete switchover to the anti-Markovnikov product, 2-phenylethan-1-ol, in the absence of O2. Raman spectroscopy, 2D 1H-1H NMR correlation experiments, and transient absorption spectroscopy establish that the site-selective control on the confined photoredox chemistry originates from an optimal preorganization of styrene molecules inside the cavity. We envision that the demonstrated host-guest charge transfer photoredox paradigm in combination with green atom-transfer reagents will enable a broad range of sp2 carbon-site functionalization.
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Affiliation(s)
- Souvik Ghosal
- Department of Chemical Sciences, Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai, 400005, India
| | - Ankita Das
- Department of Chemical Sciences, Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai, 400005, India
| | - Debojyoti Roy
- Department of Chemical Sciences, Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai, 400005, India
| | - Jyotishman Dasgupta
- Department of Chemical Sciences, Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai, 400005, India.
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3
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Bhavyesh D, Soliya S, Konakanchi R, Begari E, Ashalu KC, Naveen T. The Recent Advances in Iron-Catalyzed C(sp 3 )-H Functionalization. Chem Asian J 2023:e202301056. [PMID: 38149480 DOI: 10.1002/asia.202301056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 12/21/2023] [Accepted: 12/22/2023] [Indexed: 12/28/2023]
Abstract
The use of iron as a core metal in catalysis has become a research topic of interest over the last few decades. The reasons are clear. Iron is the most abundant transition metal on Earth's crust and it is widely distributed across the world. It has been extracted and processed since the dawn of civilization. All these features render iron a noncontaminant, biocompatible, nontoxic, and inexpensive metal and therefore it constitutes the perfect candidate to replace noble metals (rhodium, palladium, platinum, iridium, etc.). Moreover, direct C-H functionalization is one of the most efficient strategies by which to introduce new functional groups into small organic molecules. The majority of organic compounds contain C(sp3 )-H bonds. Given the enormous importance of organic molecules in so many aspects of existence, the utilization and bioactivity of C(sp3 )-H bonds are of the utmost importance. This review sheds light on the substrate scope, selectivity, benefits, and limitations of iron catalysts for direct C(sp3 )-H bond activations. An overview of the use of iron catalysis in C(sp3 )-H activation protocols is summarized herein up to 2022.
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Affiliation(s)
- Desai Bhavyesh
- Department of Chemistry, Sardar Vallabhbhai National Institute of Technology Surat, Gujarat, 395 007, India
| | - Sudha Soliya
- Department of Chemistry, Sardar Vallabhbhai National Institute of Technology Surat, Gujarat, 395 007, India
| | - Ramaiah Konakanchi
- Department of Chemistry, VNR Vignana Jyoti Institute of Engineering and Technology, Hyderabad, 500090, India
| | - Eeshwaraiah Begari
- School of Applied Material Sciences, Central University of Gujarat, Gandhinagar, 382030, India
| | - Kashamalla Chinna Ashalu
- Department of Chemistry, School of Science, Indrashil University, Rajpur, Kadi, Gujarat, 382715, India
| | - Togati Naveen
- Department of Chemistry, Sardar Vallabhbhai National Institute of Technology Surat, Gujarat, 395 007, India
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4
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Ma X, Zhang Q, Zhang W. Remote Radical 1,3-, 1,4-, 1,5-, 1,6- and 1,7-Difunctionalization Reactions. Molecules 2023; 28:molecules28073027. [PMID: 37049790 PMCID: PMC10095731 DOI: 10.3390/molecules28073027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 03/25/2023] [Accepted: 03/25/2023] [Indexed: 03/30/2023] Open
Abstract
Radical transformations are powerful in organic synthesis for the construction of molecular scaffolds and introduction of functional groups. In radical difunctionalization reactions, the radicals in the first functionalized intermediates can be relocated through resonance, hydrogen atom or group transfer, and ring opening. The resulting radical intermediates can undertake the following paths for the second functionalization: (1) couple with other radical groups, (2) oxidize to cations and then react with nucleophiles, (3) reduce to anions and then react with electrophiles, (4) couple with metal-complexes. The rearrangements of radicals provide the opportunity for the synthesis of 1,3-, 1,4-, 1,5-, 1,6-, and 1,7-difunctionalization products. Multiple ways to initiate the radical reaction coupling with intermediate radical rearrangements make the radical reactions good for difunctionalization at the remote positions. These reactions offer the advantages of synthetic efficiency, operation simplicity, and product diversity.
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Affiliation(s)
- Xiaoming Ma
- School of Pharmacy, Changzhou University, 1 Gehu Road, Changzhou 213164, China;
| | - Qiang Zhang
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, 99 Xuefu Road, Suzhou 215009, China;
| | - Wei Zhang
- Department of Chemistry and Center for Green Chemistry, University of Massachusetts Boston, 100 Morrissey Blvd, Boston, MA 02125, USA
- Correspondence: ; Tel.: +1-617-287-6147
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5
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Li M, Sun GQ, Liu YY, Li SX, Liu HC, Qiu YF, Chen DP, Wang XC, Liang YM, Quan ZJ. Nickel-Catalyzed Three-Component Tandem Radical Cyclization 1,5-Difunctionalization of 1,3-Enynes and Alkyl Bromide. J Org Chem 2023; 88:1403-1410. [PMID: 36656018 DOI: 10.1021/acs.joc.2c02271] [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
A nickel-catalyzed three-component tandem radical cyclization reaction of aryl bromides with 1,3-enynes and aryl boric acids to construct γ-lactam-substituted allene derivatives has been described. This protocol provides lactam alkyl radicals through the free radical cyclization process, which can be effectively used to participate in the subsequent multicomponent coupling reaction so that 1,3-enynes could directly convert into corresponding poly-substituted allene compounds. In addition, this efficient method enjoys a broad substrate scope and provides a series of 1,5-difunctionalized allenes in a one-pot reaction.
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Affiliation(s)
- Ming Li
- College of Chemistry and Chemical Engineering, Gansu International Scientific and Technological Cooperation Base of Water-Retention Chemical Functional Materials, Northwest Normal University, Lanzhou, Gansu 730070, China
| | - Guo-Qing Sun
- College of Chemistry and Chemical Engineering, Gansu International Scientific and Technological Cooperation Base of Water-Retention Chemical Functional Materials, Northwest Normal University, Lanzhou, Gansu 730070, China
| | - Yu-Yu Liu
- College of Chemistry and Chemical Engineering, Gansu International Scientific and Technological Cooperation Base of Water-Retention Chemical Functional Materials, Northwest Normal University, Lanzhou, Gansu 730070, China
| | - Shun-Xi Li
- College of Chemistry and Chemical Engineering, Gansu International Scientific and Technological Cooperation Base of Water-Retention Chemical Functional Materials, Northwest Normal University, Lanzhou, Gansu 730070, China
| | - Hai-Chao Liu
- College of Chemistry and Chemical Engineering, Gansu International Scientific and Technological Cooperation Base of Water-Retention Chemical Functional Materials, Northwest Normal University, Lanzhou, Gansu 730070, China
| | - Yi-Feng Qiu
- College of Chemistry and Chemical Engineering, Gansu International Scientific and Technological Cooperation Base of Water-Retention Chemical Functional Materials, Northwest Normal University, Lanzhou, Gansu 730070, China
| | - Dong-Pin Chen
- College of Chemistry and Chemical Engineering, Gansu International Scientific and Technological Cooperation Base of Water-Retention Chemical Functional Materials, Northwest Normal University, Lanzhou, Gansu 730070, China
| | - Xi-Cun Wang
- College of Chemistry and Chemical Engineering, Gansu International Scientific and Technological Cooperation Base of Water-Retention Chemical Functional Materials, Northwest Normal University, Lanzhou, Gansu 730070, China
| | - Yong-Min Liang
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Zheng-Jun Quan
- College of Chemistry and Chemical Engineering, Gansu International Scientific and Technological Cooperation Base of Water-Retention Chemical Functional Materials, Northwest Normal University, Lanzhou, Gansu 730070, China
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6
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Ding H, Zhang S, Sun Z, Ma Q, Li Y, Yuan Y, Jia X. C-H Bond Activation Relay (CHAR) of Proline Ester Derivatives Promoted by In Situ Triarylamine Radical Cation: Selective Synthesis of 4-Bromopyrrole Derivatives. Chemistry 2023; 29:e202203654. [PMID: 36727278 DOI: 10.1002/chem.202203654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 01/14/2023] [Accepted: 02/01/2023] [Indexed: 02/03/2023]
Abstract
Using the in situ generated triarylamine radical cation as an initiator, the sp3 C-H bond of proline esters was smoothly oxidized and brominated through C-H activation relay (CHAR), giving a series of 4-bromopyrroles in good yields with high regioselectivity. The mechanistic study revealed that the oxidation of the active C-H bond initiated the followed 1,5-HAT and bromination, which provides a new method to realize the functionalization of the remote C-H bond.
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Affiliation(s)
- Han Ding
- School of Chemistry and Chemical Engineering, Yangzhou University, Siwangting Road 180, 225002, Yangzhou, Jiangsu, P. R. China
| | - Shuwei Zhang
- School of Chemistry and Chemical Engineering, Yangzhou University, Siwangting Road 180, 225002, Yangzhou, Jiangsu, P. R. China
| | - Zheng Sun
- School of Chemistry and Chemical Engineering, Yangzhou University, Siwangting Road 180, 225002, Yangzhou, Jiangsu, P. R. China
| | - Qiyuan Ma
- School of Chemistry and Chemical Engineering, Yangzhou University, Siwangting Road 180, 225002, Yangzhou, Jiangsu, P. R. China
| | - Yuemei Li
- School of Chemistry and Chemical Engineering, Yangzhou University, Siwangting Road 180, 225002, Yangzhou, Jiangsu, P. R. China
| | - Yu Yuan
- School of Chemistry and Chemical Engineering, Yangzhou University, Siwangting Road 180, 225002, Yangzhou, Jiangsu, P. R. China
| | - Xiaodong Jia
- School of Chemistry and Chemical Engineering, Yangzhou University, Siwangting Road 180, 225002, Yangzhou, Jiangsu, P. R. China
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7
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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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8
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Wang L, Shu S, Lv L, Li Z. Copper-catalyzed remote trifluoromethylthiolation-peroxidation of unactivated alkenes via 1,5-hydrogen atom transfer. Tetrahedron Lett 2022. [DOI: 10.1016/j.tetlet.2022.154029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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9
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Bian KJ, Nemoto D, Kao SC, He Y, Li Y, Wang XS, West JG. Modular Difunctionalization of Unactivated Alkenes through Bio-Inspired Radical Ligand Transfer Catalysis. J Am Chem Soc 2022; 144:11810-11821. [PMID: 35729791 DOI: 10.1021/jacs.2c04188] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Development of visible light-mediated atom transfer radical addition of haloalkanes onto unsaturated hydrocarbons has seen rapid growth in recent years. However, due to its radical chain propagation mechanism, diverse functionality other than the pre-existing (pseudo-)halide on the alkyl halide source cannot be incorporated into target molecules in a one-step, economic fashion. Inspired by the prominent reactivities shown by cytochrome P450 hydroxylase and non-heme iron-dependent oxygenases, we herein report the first modular, dual catalytic difunctionalization of unactivated alkenes via manganese-catalyzed radical ligand transfer (RLT). This RLT elementary step involves a coordinated nucleophile rebounding to a carbon-centered radical to form a new C-X bond in analogy to the radical rebound step in metalloenzymes. The protocol leverages the synergetic cooperation of both a photocatalyst and earth-abundant manganese complex to deliver two radical species in succession to minimally functionalized alkenes, enabling modular diversification of the radical intermediate by a high-valent manganese species capable of delivering various external nucleophiles. A broad scope (97 examples, including drugs/natural product motifs), mild conditions, and excellent chemoselectivity were shown for a variety of substrates and fluoroalkyl fragments. Mechanistic and kinetics studies provide insights into the radical nature of the dual catalytic transformation and support radical ligand transfer (RLT) as a new strategy to deliver diverse functionality selectively to carbon-centered radicals.
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Affiliation(s)
- Kang-Jie Bian
- Department of Chemistry, Rice University, 6500 Main St, Houston, Texas 77030, United States
| | - David Nemoto
- Department of Chemistry, Rice University, 6500 Main St, Houston, Texas 77030, United States
| | - Shih-Chieh Kao
- Department of Chemistry, Rice University, 6500 Main St, Houston, Texas 77030, United States
| | - Yan He
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Yan Li
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Xi-Sheng Wang
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Julian G West
- Department of Chemistry, Rice University, 6500 Main St, Houston, Texas 77030, United States
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10
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Abe M, Yokoi Y, Hirata A, Matsuoka Y, Kimachi T, Inamoto K. Site-selective iodine atom transfer in fluorinated alkyl iodides via 1,5-hydrogen atom transfer. Chem Commun (Camb) 2022; 58:7416-7418. [PMID: 35695135 DOI: 10.1039/d2cc02803d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The direct and selective functionalization of inert C-H bonds via intramolecular hydrogen atom transfer (HAT) is an increasingly powerful tool in organic synthesis. Herein, we designed an efficient and facile iodine atom transfer in fluorinated alkyl iodides via 1,5-HAT. Our process enables site-selective iodination of unreactive C(sp3)-H bonds to afford di- and tri-fluorinated alkyl iodides in good yields. Furthermore, our process shows excellent atom economy and high functional group tolerance, including methyl, methoxy, chloro, cyano, and silyl moieties.
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Affiliation(s)
- Masahiro Abe
- School of Pharmacy and Pharmaceutical Sciences, Mukogawa Women's University, 11-68, 9-Bancho, Koshien, Nishinomiya, Hyogo 663-8179, Japan.
| | - Yuka Yokoi
- School of Pharmacy and Pharmaceutical Sciences, Mukogawa Women's University, 11-68, 9-Bancho, Koshien, Nishinomiya, Hyogo 663-8179, Japan.
| | - Aoi Hirata
- School of Pharmacy and Pharmaceutical Sciences, Mukogawa Women's University, 11-68, 9-Bancho, Koshien, Nishinomiya, Hyogo 663-8179, Japan.
| | - Yumeno Matsuoka
- School of Pharmacy and Pharmaceutical Sciences, Mukogawa Women's University, 11-68, 9-Bancho, Koshien, Nishinomiya, Hyogo 663-8179, Japan.
| | - Tetsutaro Kimachi
- School of Pharmacy and Pharmaceutical Sciences, Mukogawa Women's University, 11-68, 9-Bancho, Koshien, Nishinomiya, Hyogo 663-8179, Japan.
| | - Kiyofumi Inamoto
- School of Pharmacy and Pharmaceutical Sciences, Mukogawa Women's University, 11-68, 9-Bancho, Koshien, Nishinomiya, Hyogo 663-8179, Japan.
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11
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Li X, Shui Y, Shen P, Wang YP, Zhang C, Feng C. A novel type of radical-addition-induced β-fragmentation and ensuing remote functionalization. Chem 2022. [DOI: 10.1016/j.chempr.2022.05.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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12
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Xi JM, Sun YH, Li WC, Wu YH, Wei ZL, Liao WW. Radical Alkene-Trifluoromethylation-Triggered Nitrile Insertion/Remote Functionalization Relay Processes: Diverse Synthesis of Trifluoromethylated Azaheterocycles Enabled by Copper Catalysis. Org Lett 2022; 24:1110-1115. [PMID: 35080394 DOI: 10.1021/acs.orglett.2c00083] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A copper-catalyzed alkene-trifluoromethylation-triggered nitrile insertion/remote functionalization relay process has been achieved, in which "interrupted" remote 1,n-difunctionalizations of alkenes with nitrile insertion can deliver iminyl radical intermediates instead of C-based radicals, followed by subsequent 1,n-HAT to furnish corresponding remote functionalization. This relay protocol enables a straightforward approach to streamline the assembly of structurally diverse trifluoromethylated azaheterocycles.
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Affiliation(s)
- Ji-Ming Xi
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Yun-Hai Sun
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Wen-Cheng Li
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Yu-Heng Wu
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Zhong-Lin Wei
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Wei-Wei Liao
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China.,State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, P. R. China
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13
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Wang L, Lv L, Li Z. Concomitant Functionalization of Two Different Ketones by Merging Brønsted Acid Catalysis and Radical Relay Coupling. Org Chem Front 2022. [DOI: 10.1039/d1qo01787j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In previous literature, incorporation of functional groups at the α-position of unactivated carbonyl compounds was mainly restricted to one kind of corresponding precursors. Herein, we report the concomitant functionalization of...
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14
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Jiang X, zheng Z, Gao Y, Lan D, Xu W, Wang Z, Chen G. Synthesis of Tetrasubstituted Alkenyl Nitriles via Cyanocarbene Addition of [1.1.1]Propellane. Org Chem Front 2022. [DOI: 10.1039/d2qo00186a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herein, we report the metal-free synthesis of methylenecyclobutane containing tetrasubstituted alkenyl nitriles via a strain-release driven addition reaction of [1.1.1]propellane under mild conditions. Using this strategy, TMSN3 was shown to...
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15
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Xi JM, Liao WW. Radical addition to the CC bond meets (1, n)-HAT: recent advances in the remote C(sp 3)–H or C(sp 2)–H functionalization of alkenes. Org Chem Front 2022. [DOI: 10.1039/d2qo00793b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This review summarizes the recent development of remote C(sp3)–H bond or aldehydic C(sp2)–H functionalizations enabled by intermolecular radical addition to CC bond/(1,n)-HAT tandem sequences.
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Affiliation(s)
- Ji-Ming Xi
- Department of Organic Chemistry, College of Chemistry, Jilin University, Changchun 130012, P. R. China
| | - Wei-Wei Liao
- Department of Organic Chemistry, College of Chemistry, Jilin University, Changchun 130012, P. R. China
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, P. R. China
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16
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Chang C, Zhang H, Wu X, Zhu C. Radical trifunctionalization of hexenenitrile via remote cyano migration. Chem Commun (Camb) 2021; 58:1005-1008. [PMID: 34940775 DOI: 10.1039/d1cc06687k] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel radical-mediated trifunctionalization of hexenenitriles via the strategy of remote functional group migration is disclosed. A portfolio of functionalized hexenenitriles are employed as substrates. After difunctionalization of the unactivated alkenyl part via remote cyano migration, the in situ formed radical intermediate is captured by an azido radical, thus enabling the trifunctionalization. The reaction features mild conditions and broad functional group compatibility, leading to valuable products bearing multiple useful groups. This protocol further extends the scope of remote functional group migration.
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Affiliation(s)
- Chenyang Chang
- 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.
| | - Huihui Zhang
- 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.
| | - Chen Zhu
- 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. .,Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
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17
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Kanno S, Kakiuchi F, Kochi T. Palladium-Catalyzed Remote Diborylative Cyclization of Dienes with Diborons via Chain Walking. J Am Chem Soc 2021; 143:19275-19281. [PMID: 34695350 DOI: 10.1021/jacs.1c09705] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
A novel method for catalytic remote bismetalation of alkene substrates by the addition of dimetal reagents is accomplished by using chain walking. In the presence of a palladium catalyst, the reaction of various 1,n-dienes and diborons were converted into cyclopentane derivatives with two boryl groups at remote positions via facile regioselective transformation of an unactivated sp3 C-H bond to a C-B bond. Sequential construction of three distant bonds, which is difficult to achieve by any method, was accomplished for the reactions of 1,n-dienes (n ≥ 7).
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Affiliation(s)
- Shota Kanno
- Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan
| | - Fumitoshi Kakiuchi
- Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan
| | - Takuya Kochi
- Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan
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18
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Zhao Y, Wang X, Yao R, Li C, Xu Z, Zhang L, Han G, Hou J, Liu Y, Song Y. Iron‐Catalyzed Alkene Trifluoromethylation in Tandem with Phenol Dearomatizing Spirocyclization: Regioselective Construction of Trifluoromethylated Spirocarbocycles. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202101201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Yilin Zhao
- Tianjin Key Laboratory of Technologies Enabling Development of Clinical Therapeutics and Diagnostics School of Pharmacy The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics School of Basic Medical Sciences Tianjin Medical University Tianjin 300070 People's Republic of China
| | - Xue Wang
- Tianjin Key Laboratory of Technologies Enabling Development of Clinical Therapeutics and Diagnostics School of Pharmacy The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics School of Basic Medical Sciences Tianjin Medical University Tianjin 300070 People's Republic of China
| | - Ru Yao
- Tianjin Key Laboratory of Technologies Enabling Development of Clinical Therapeutics and Diagnostics School of Pharmacy The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics School of Basic Medical Sciences Tianjin Medical University Tianjin 300070 People's Republic of China
| | - Chengwen Li
- Tianjin Key Laboratory of Technologies Enabling Development of Clinical Therapeutics and Diagnostics School of Pharmacy The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics School of Basic Medical Sciences Tianjin Medical University Tianjin 300070 People's Republic of China
| | - Zelin Xu
- Tianjin Key Laboratory of Technologies Enabling Development of Clinical Therapeutics and Diagnostics School of Pharmacy The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics School of Basic Medical Sciences Tianjin Medical University Tianjin 300070 People's Republic of China
| | - Liming Zhang
- Tianjin Key Laboratory of Technologies Enabling Development of Clinical Therapeutics and Diagnostics School of Pharmacy The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics School of Basic Medical Sciences Tianjin Medical University Tianjin 300070 People's Republic of China
| | - Guifang Han
- Tianjin Key Laboratory of Technologies Enabling Development of Clinical Therapeutics and Diagnostics School of Pharmacy The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics School of Basic Medical Sciences Tianjin Medical University Tianjin 300070 People's Republic of China
| | - Jingli Hou
- Tianjin Key Laboratory of Technologies Enabling Development of Clinical Therapeutics and Diagnostics School of Pharmacy The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics School of Basic Medical Sciences Tianjin Medical University Tianjin 300070 People's Republic of China
| | - Yangping Liu
- Tianjin Key Laboratory of Technologies Enabling Development of Clinical Therapeutics and Diagnostics School of Pharmacy The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics School of Basic Medical Sciences Tianjin Medical University Tianjin 300070 People's Republic of China
| | - Yuguang Song
- Tianjin Key Laboratory of Technologies Enabling Development of Clinical Therapeutics and Diagnostics School of Pharmacy The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics School of Basic Medical Sciences Tianjin Medical University Tianjin 300070 People's Republic of China
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19
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Abstract
The first iron-catalyzed asymmetric azidation of benzylic peresters has been reported with trimethylsilyl azide (TMSN3) as the azido source. Hydrocarbon radicals that lack of strong interactions were capable to be enantioselectively azidated. The reaction features good functional group tolerance, high yields, and mild conditions. The chiral benzylic azides can further be used in click reaction, phosphoramidation, and reductive amination, which demonstrate the synthetic values of this reaction.
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Affiliation(s)
- Kaikai Wang
- Fujian Key Laboratory of Innate Immune Biology, Biomedical Research Center of South China, Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou 350007, People's Republic of China.,Key Laboratory of Coal to Ethylene Glycol and Its Related Technology, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, People's Republic of China
| | - Yajun Li
- Key Laboratory of Coal to Ethylene Glycol and Its Related Technology, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, People's Republic of China
| | - Xiaoyan Li
- Key Laboratory of Coal to Ethylene Glycol and Its Related Technology, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, People's Republic of China.,University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Daliang Li
- Fujian Key Laboratory of Innate Immune Biology, Biomedical Research Center of South China, Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou 350007, People's Republic of China
| | - Hongli Bao
- Key Laboratory of Coal to Ethylene Glycol and Its Related Technology, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, People's Republic of China.,University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
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20
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Tang K, Chen Y, Guan J, Wang Z, Chen K, Xiang H, Yang H. Visible-light-promoted olefinic trifluoromethylation of enamides with CF 3SO 2Na. Org Biomol Chem 2021; 19:7475-7479. [PMID: 34612366 DOI: 10.1039/d1ob01410b] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
A visible-light-promoted olefinic C-H trifluoromethylation of enamides was developed by employing cheap and stable Langlois' reagent as the CF3 source. A series of β-CF3 enamides were obtained in moderate to good yields with high E-isomer selectivity under mild conditions. Preliminary mechanistic studies suggest that molecular oxygen acts as the terminal oxidant for this net oxidative process, and the E isomer selectivity could be well explained by a base-assisted deprotonation of the cation intermediate.
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Affiliation(s)
- Kai Tang
- College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
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21
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Wang L, Ma Y, Jiang Y, Lv L, Li Z. A Mn-catalyzed remote C(sp 3)-H bond peroxidation triggered by radical trifluoromethylation of unactivated alkenes. Chem Commun (Camb) 2021; 57:7846-7849. [PMID: 34278408 DOI: 10.1039/d1cc03295j] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
A manganese-catalyzed radical relay strategy for the remote trifluoromethylation-peroxidation of unactivated alkenes is disclosed. The electrophilic CF3 group was added to the C[double bond, length as m-dash]C double bonds to afford remote C-centered radicals upon 1,5-HAT, which could be efficiently trapped by Mnn+1OOBu-t species to deliver 1,6-difunctionalized products selectively under mild conditions. t-BuOOH serves as both the oxidant and the peroxy precursor in this transformation.
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Affiliation(s)
- Leilei Wang
- Department of Chemistry, Renmin University of China, Beijing 100872, China.
| | - Yangyang Ma
- Department of Chemistry, Renmin University of China, Beijing 100872, China.
| | - Yuhang Jiang
- Department of Chemistry, Renmin University of China, Beijing 100872, China.
| | - Leiyang Lv
- Department of Chemistry, Renmin University of China, Beijing 100872, China.
| | - Zhiping Li
- Department of Chemistry, Renmin University of China, Beijing 100872, China.
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22
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Liu J, Wei Y, Shi M. Direct Activation of a Remote C(sp 3 )-H Bond Enabled by a Visible-Light Photosensitized Allene Moiety. Angew Chem Int Ed Engl 2021; 60:12053-12059. [PMID: 33719146 DOI: 10.1002/anie.202101266] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 03/02/2021] [Indexed: 12/14/2022]
Abstract
Despite allene derivatives have been always regarded as a radical accepter in traditional radical chemistry for decades, the reactivity of allene derivatives under excited state in radical chemistry was rarely explored. Herein, we wish to report an example to engage triplet-excited state of allene moiety as hydrogen-atom-transfer (HAT) partner in the activation of remote sp3 C-H bond via visible-light irradiation under mild reaction conditions with broad substrate scope and good functional-group tolerance. The reaction mechanism involving the generation of triplet excited state of allene derivative and the subsequent HAT process was supported by deuterium labeling, kinetic analysis experiments and DFT calculations.
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Affiliation(s)
- Jiaxin Liu
- State Key Laboratory of Organometallic Chemistry, University of Chinese Academy of Sciences, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China
| | - Yin Wei
- State Key Laboratory of Organometallic Chemistry, University of Chinese Academy of Sciences, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China
| | - Min Shi
- State Key Laboratory of Organometallic Chemistry, University of Chinese Academy of Sciences, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China
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23
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Liu J, Wei Y, Shi M. Direct Activation of a Remote C(sp
3
)–H Bond Enabled by a Visible‐Light Photosensitized Allene Moiety. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202101266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Jiaxin Liu
- State Key Laboratory of Organometallic Chemistry University of Chinese Academy of Sciences Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 China
| | - Yin Wei
- State Key Laboratory of Organometallic Chemistry University of Chinese Academy of Sciences Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 China
| | - Min Shi
- State Key Laboratory of Organometallic Chemistry University of Chinese Academy of Sciences Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 China
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24
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Affiliation(s)
- Paramasivam Sivaguru
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Northeast Normal University, Changchun 130024, China
| | - Yongquan Ning
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Northeast Normal University, Changchun 130024, China
| | - Xihe Bi
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Northeast Normal University, Changchun 130024, China
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25
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Jin RX, Dai JC, Li Y, Wang XS. Copper-Catalyzed Intramolecular Amination of C(sp 3)-H Bond of Secondary Amines to Access Azacycles. Org Lett 2021; 23:421-426. [PMID: 33395308 DOI: 10.1021/acs.orglett.0c03934] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The cross-coupling of C-N bond directly from inert C-H bonds is an ideal approach to synthesize saturated azacycles due to its high efficiency and atom economy. In this article, a copper-catalyzed intramolecular amination via the cross coupling of C(sp3)-H and N-H bonds of secondary amine has been reported, which exhibit excellent chemo- and regioselectivity, extensive substrate scope, and functional group tolerance in good to excellent yield, offering an efficient pathway to build nitrogen-containing heterocycle skeletons.
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Affiliation(s)
- Ruo-Xing Jin
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Jing-Cheng Dai
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Yan Li
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Xi-Sheng Wang
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
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26
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27
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Zhong LJ, Li Y, An DL, Li JH. Heteroannulation of N-Fluoro-N-alkylsulfonamides with Terminal Alkynes via Remote C(sp3)–H Functionalization. ACS Catal 2020. [DOI: 10.1021/acscatal.0c03853] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Long-Jin Zhong
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, China
| | - Yang Li
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, China
| | - De-Lie An
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, China
| | - Jin-Heng Li
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, China
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, China
- Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research (Ministry of Education), Hunan Normal University, Changsha 410081, China
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
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28
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Bam R, Pollatos AS, Moser AJ, West JG. Mild olefin formation via bio-inspired vitamin B 12 photocatalysis. Chem Sci 2020; 12:1736-1744. [PMID: 34163933 PMCID: PMC8179286 DOI: 10.1039/d0sc05925k] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Dehydrohalogenation, or elimination of hydrogen-halide equivalents, remains one of the simplest methods for the installation of the biologically-important olefin functionality. However, this transformation often requires harsh, strongly-basic conditions, rare noble metals, or both, limiting its applicability in the synthesis of complex molecules. Nature has pursued a complementary approach in the novel vitamin B12-dependent photoreceptor CarH, where photolysis of a cobalt–carbon bond leads to selective olefin formation under mild, physiologically-relevant conditions. Herein we report a light-driven B12-based catalytic system that leverages this reactivity to convert alkyl electrophiles to olefins under incredibly mild conditions using only earth abundant elements. Further, this process exhibits a high level of regioselectivity, producing terminal olefins in moderate to excellent yield and exceptional selectivity. Finally, we are able to access a hitherto-unknown transformation, remote elimination, using two cobalt catalysts in tandem to produce subterminal olefins with excellent regioselectivity. Together, we show vitamin B12 to be a powerful platform for developing mild olefin-forming reactions. Terminal or subterminal olefins can be selectively formed from alkyl electrophiles via bio-inspired vitamin B12 photocatalysis.![]()
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Affiliation(s)
- Radha Bam
- Department of Chemistry, Rice University 6500 Main St Houston TX USA .westchem.org
| | | | - Austin J Moser
- Department of Chemistry, Rice University 6500 Main St Houston TX USA .westchem.org
| | - Julian G West
- Department of Chemistry, Rice University 6500 Main St Houston TX USA .westchem.org
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29
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Sarkar S, Cheung KPS, Gevorgyan V. C-H functionalization reactions enabled by hydrogen atom transfer to carbon-centered radicals. Chem Sci 2020; 11:12974-12993. [PMID: 34123240 PMCID: PMC8163321 DOI: 10.1039/d0sc04881j] [Citation(s) in RCA: 136] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 11/14/2020] [Indexed: 12/12/2022] Open
Abstract
Selective functionalization of ubiquitous unactivated C-H bonds is a continuous quest for synthetic organic chemists. In addition to transition metal catalysis, which typically operates under a two-electron manifold, a recent renaissance in the radical approach relying on the hydrogen atom transfer (HAT) process has led to tremendous growth in the area. Despite several challenges, protocols proceeding via HAT are highly sought after as they allow for relatively easy activation of inert C-H bonds under mild conditions leading to a broader scope and higher functional group tolerance and sometimes complementary reactivity over methods relying on traditional transition metal catalysis. A number of methods operating via heteroatom-based HAT have been extensively reported over the past few years, while methods employing more challenging carbon analogues have been less explored. Recent developments of mild methodologies for generation of various carbon-centered radical species enabled their utilization in the HAT process, which, in turn, led to the development of remote C(sp3)-H functionalization reactions of alcohols, amines, amides and related compounds. This review covers mostly recent advances in C-H functionalization reactions involving the HAT step to carbon-centered radicals.
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Affiliation(s)
- Sumon Sarkar
- Department of Chemistry and Biochemistry, University of Texas at Dallas 800 W Campbell Rd Richardson Texas 75080 USA
| | - Kelvin Pak Shing Cheung
- Department of Chemistry and Biochemistry, University of Texas at Dallas 800 W Campbell Rd Richardson Texas 75080 USA
| | - Vladimir Gevorgyan
- Department of Chemistry and Biochemistry, University of Texas at Dallas 800 W Campbell Rd Richardson Texas 75080 USA
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