1
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Flach M, Hirsch K, Gitzinger T, Timm M, da Silva Santos M, Ablyasova OS, Kubin M, von Issendorff B, Lau JT, Zamudio-Bayer V. Abrupt Change from Ionic to Covalent Bonding in Nickel Halides Accompanied by Ligand Field Inversion. Inorg Chem 2024. [PMID: 38857413 DOI: 10.1021/acs.inorgchem.4c01547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2024]
Abstract
The electronic configuration of transition metal centers and their ligands is crucial for redox reactions in metal catalysis and electrochemistry. We characterize the electronic structure of gas-phase nickel monohalide cations via nickel L2,3-edge X-ray absorption spectroscopy. Comparison with multiplet charge-transfer simulations and experimental spectra of selectively prepared nickel monocations in both ground- and excited-state configurations are used to facilitate our analysis. Only for [NiF]+ with an assigned ground state of 3Π can the bonding be described as predominantly ionic, while the heavier halides with assigned ground states of 3Π or 3Δ exhibit a predominantly covalent contribution. The increase in covalency is accompanied by a transition from a classical ligand field for [NiF]+ to an inverted ligand field for [NiCl]+, [NiBr]+, and [NiI]+, resulting in a leading 3d9 L̲ configuration with a ligand hole (L̲) and a 3d occupation indicative of nickel(I) compounds. Hence, the absence of a ligand hole in [NiF]+ precludes any ligand-based redox reactions. Additionally, we demonstrate that the shift in energy of the L3 resonance is reduced compared to that of isolated atoms upon the formation of covalent compounds.
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Affiliation(s)
- Max Flach
- Abteilung für Hochempfindliche Röntgenspektroskopie, Helmholtz-Zentrum Berlin für Materialien and Energie, Berlin 12489, Germany
- Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg 79104, Germany
| | - Konstantin Hirsch
- Abteilung für Hochempfindliche Röntgenspektroskopie, Helmholtz-Zentrum Berlin für Materialien and Energie, Berlin 12489, Germany
| | - Tim Gitzinger
- Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg 79104, Germany
| | - Martin Timm
- Abteilung für Hochempfindliche Röntgenspektroskopie, Helmholtz-Zentrum Berlin für Materialien and Energie, Berlin 12489, Germany
| | - Mayara da Silva Santos
- Abteilung für Hochempfindliche Röntgenspektroskopie, Helmholtz-Zentrum Berlin für Materialien and Energie, Berlin 12489, Germany
- Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg 79104, Germany
| | - Olesya S Ablyasova
- Abteilung für Hochempfindliche Röntgenspektroskopie, Helmholtz-Zentrum Berlin für Materialien and Energie, Berlin 12489, Germany
- Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg 79104, Germany
| | - Markus Kubin
- Abteilung für Hochempfindliche Röntgenspektroskopie, Helmholtz-Zentrum Berlin für Materialien and Energie, Berlin 12489, Germany
| | - Bernd von Issendorff
- Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg 79104, Germany
| | - J Tobias Lau
- Abteilung für Hochempfindliche Röntgenspektroskopie, Helmholtz-Zentrum Berlin für Materialien and Energie, Berlin 12489, Germany
- Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg 79104, Germany
| | - Vicente Zamudio-Bayer
- Abteilung für Hochempfindliche Röntgenspektroskopie, Helmholtz-Zentrum Berlin für Materialien and Energie, Berlin 12489, Germany
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2
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Yan W, Poore AT, Yin L, Carter S, Ho YS, Wang C, Yachuw SC, Cheng YH, Krause JA, Cheng MJ, Zhang S, Tian S, Liu W. Catalytically Relevant Organocopper(III) Complexes Formed through Aryl-Radical-Enabled Oxidative Addition. J Am Chem Soc 2024; 146:15176-15185. [PMID: 38770641 DOI: 10.1021/jacs.4c01668] [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
Stepwise oxidative addition of copper(I) complexes to form copper(III) species via single electron transfer (SET) events has been widely proposed in copper catalysis. However, direct observation and detailed investigation of these fundamental steps remain elusive owing largely to the typically slow oxidative addition rate of copper(I) complexes and the instability of the copper(III) species. We report herein a novel aryl-radical-enabled stepwise oxidative addition pathway that allows for the formation of well-defined alkyl-CuIII species from CuI complexes. The process is enabled by the SET from a CuI species to an aryl diazonium salt to form a CuII species and an aryl radical. Subsequent iodine abstraction from an alkyl iodide by the aryl radical affords an alkyl radical, which then reacts with the CuII species to form the alkyl-CuIII complex. The structure of resultant [(bpy)CuIII(CF3)2(alkyl)] complexes has been characterized by NMR spectroscopy and X-ray crystallography. Competition experiments have revealed that the rate at which different alkyl iodides undergo oxidative addition is consistent with the rate of iodine abstraction by carbon-centered radicals. The CuII intermediate formed during the SET process has been identified as a four-coordinate complex, [CuII(CH3CN)2(CF3)2], through electronic paramagnetic resonance (EPR) studies. The catalytic relevance of the high-valent organo-CuIII has been demonstrated by the C-C bond-forming reductive elimination reactivity. Finally, localized orbital bonding analysis of these formal CuIII complexes indicates inverted ligand fields in σ(Cu-CH2) bonds. These results demonstrate the stepwise oxidative addition in copper catalysis and provide a general strategy to investigate the elusive formal CuIII complexes.
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Affiliation(s)
- Wenhao Yan
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Andrew T Poore
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Lingfeng Yin
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Samantha Carter
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Yeu-Shiuan Ho
- Department of Chemistry, National Cheng Kung University, Tainan 701, Taiwan
| | - Chao Wang
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Stephen C Yachuw
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Yu-Ho Cheng
- Department of Chemistry, National Cheng Kung University, Tainan 701, Taiwan
| | - Jeanette A Krause
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Mu-Jeng Cheng
- Department of Chemistry, National Cheng Kung University, Tainan 701, Taiwan
| | - Shiyu Zhang
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Shiliang Tian
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Wei Liu
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
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3
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Patra S, Nandasana BN, Valsamidou V, Katayev D. Mechanochemistry Drives Alkene Difunctionalization via Radical Ligand Transfer and Electron Catalysis. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024:e2402970. [PMID: 38829256 DOI: 10.1002/advs.202402970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 05/08/2024] [Indexed: 06/05/2024]
Abstract
A general and modular protocol is reported for olefin difunctionalization through mechanochemistry, facilitated by cooperative radical ligand transfer (RLT) and electron catalysis. Utilizing mechanochemical force and catalytic amounts of 2,2,6,6-tetramethylpiperidinyloxyl (TEMPO), ferric nitrate can leverage nitryl radicals, transfer nitrooxy-functional group via RLT, and mediate an electron catalysis cycle under room temperature. A diverse range of activated and unactivated alkenes exhibited chemo- and regioselective 1,2-nitronitrooxylation under solvent-free or solvent-less conditions, showcasing excellent functional group tolerance. Mechanistic studies indicated a significant impact of mechanochemistry and highlighted the radical nature of this nitrative difunctionalization process.
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Affiliation(s)
- Subrata Patra
- Department of Chemistry, Biochemistry, and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, Bern, 3012, Switzerland
| | - Bhargav N Nandasana
- Department of Chemistry, Biochemistry, and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, Bern, 3012, Switzerland
| | - Vasiliki Valsamidou
- Department of Chemistry, Biochemistry, and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, Bern, 3012, Switzerland
| | - Dmitry Katayev
- Department of Chemistry, Biochemistry, and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, Bern, 3012, Switzerland
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4
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Zhao Y, Zhang J, Zhan ZJ, Fan Q, Xiao XQ, Bai Y, Ni SF, Shao X. Synthesis of Azo-Substituted Bicyclo[1.1.1]pentanes (BCPs) via Base-Promoted Halogen Atom Transfer. Org Lett 2024; 26:4406-4410. [PMID: 38742800 DOI: 10.1021/acs.orglett.4c01546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Because of the three-dimensional bioisosteric feature, bicyclo[1.1.1]pentylamines (BCPAs) are valuable scaffolds in synthetic chemistry and medicinal chemistry. Here, we report a Halogen Atom Transfer (XAT) mediated radical C-N coupling between C3-iodo-BCPs and diazonium salts in the presence of base. Similarly, a multicomponent reaction (MCR) enables the simultaneous construction of the C-C bond and C-N bond simultaneously. Versatile roles of diazonium salts were also explored.
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Affiliation(s)
- Yanchuang Zhao
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, P. R. China
| | - Jing Zhang
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, P. R. China
| | - Zhi-Jin Zhan
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guang-dong Province, Shantou University, Shantou 515063, P. R. China
| | - Qiujin Fan
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, P. R. China
| | - Xu-Qiong Xiao
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, P. R. China
| | - Ying Bai
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, P. R. China
| | - Shao-Fei Ni
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guang-dong Province, Shantou University, Shantou 515063, P. R. China
| | - Xinxin Shao
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, P. R. China
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5
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Li Z, Zeng G, He Y, Zhou S, Chen J, Chen Z, Chen J, Lv N. Markovnikov Hydrochlorination of Unactivated Alkenes with FeCl 3 via a HAT/XAT Sequence. Org Lett 2024. [PMID: 38780034 DOI: 10.1021/acs.orglett.4c01647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
Hydrochlorination of alkenes is a practical strategy for accessing organic chlorides. Herein, we report the hydrochlorination of unactivated alkenes via a hydrogen atom transfer/halogen atom transfer process using earth-abundant and biocompatible FeCl3 as a chlorine source under extraordinarily mild reaction conditions. The protocol is easy to operate with notable features such as excellent chemoselectivity, remarkable efficiency, a broad substrate scope, and good functional group tolerance. Importantly, the synthetic utility is highlighted by scaled-up reactions, late-stage derivatizations of products, and the modification of sulfonamides.
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Affiliation(s)
- Zhefeng Li
- College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou 325035, China
| | - Ge Zeng
- College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou 325035, China
| | - Yequan He
- College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou 325035, China
| | - Si Zhou
- College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou 325035, China
| | - Juehong Chen
- College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou 325035, China
| | - Zhongyan Chen
- College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou 325035, China
- Key Lab of Biohealth Materials and Chemistry of Wenzhou, Wenzhou 325035, China
| | - Jiuxi Chen
- College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou 325035, China
| | - Ningning Lv
- College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou 325035, China
- Key Lab of Biohealth Materials and Chemistry of Wenzhou, Wenzhou 325035, China
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6
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Lee J, Lee S. Dehalogenative deuteration of alkyl and aryl bromides by thiyl radical catalysis under visible-light irradiation. Chem Commun (Camb) 2024; 60:5526-5529. [PMID: 38695506 DOI: 10.1039/d4cc00474d] [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
Herein, we report a mild and practical method for the deuteration of alkyl and aryl bromides by a thiyl radical catalyst and halogen-atom transfer (XAT) using disulfides and silanes under visible-light irradiation. In this study, various organic bromides such as 1°, 2°, and 3°-alkyl bromides and aryl bromides were converted to deuterated products in good to excellent yields and D-incorporation.
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Affiliation(s)
- Jiin Lee
- Department of Physics and Chemistry, DGIST, Daegu 42988, Republic of Korea.
| | - Sunggi Lee
- Department of Physics and Chemistry, DGIST, Daegu 42988, Republic of Korea.
- Center for Basic Science, DGIST, Daegu 42988, Republic of Korea
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7
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Di Terlizzi L, Nicchio L, Protti S, Fagnoni M. Visible photons as ideal reagents for the activation of coloured organic compounds. Chem Soc Rev 2024; 53:4926-4975. [PMID: 38596901 DOI: 10.1039/d3cs01129a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
In recent decades, the traceless nature of visible photons has been exploited for the development of efficient synthetic strategies for the photoconversion of colourless compounds, namely, photocatalysis, chromophore activation, and the formation of an electron donor/acceptor (EDA) complex. However, the use of photoreactive coloured organic compounds is the optimal strategy to boost visible photons as ideal reagents in synthetic protocols. In view of such premises, the present review aims to provide its readership with a collection of recent photochemical strategies facilitated via direct light absorption by coloured molecules. The protocols have been classified and presented according to the nature of the intermediate/excited state achieved during the transformation.
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Affiliation(s)
- Lorenzo Di Terlizzi
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy.
| | - Luca Nicchio
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy.
| | - Stefano Protti
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy.
| | - Maurizio Fagnoni
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy.
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8
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Gutiérrez-González A, Karlsson S, Leonori D, Plesniak MP. Mild Strategy for the Preparation of Alkyl Sulfonyl Fluorides from Alkyl Bromides and Alcohols Using Photoredox Catalysis and Flow Chemistry. Org Lett 2024; 26:3972-3976. [PMID: 38663015 DOI: 10.1021/acs.orglett.4c01216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2024]
Abstract
Facile access to sp3-rich scaffolds containing a sulfonyl fluoride group is still limited. Herein, we describe a mild and scalable strategy for the preparation of alkyl sulfonyl fluorides from readily available alkyl bromides and alcohols using photoredox catalysis. This approach is based on halogen atom transfer (XAT), followed by SO2 capture and fluorination. The method features mild conditions enabling fast access to high-value derivatives and has been scaled up to 5 g using a continuous stirred tank reactor cascade.
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Affiliation(s)
- Alejandro Gutiérrez-González
- Medicinal Chemistry, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca Gothenburg, 431 83 Mölndal, Sweden
| | - Staffan Karlsson
- Early Chemical Development, Pharmaceutical Sciences, Biopharmaceuticals R&D, AstraZeneca Gothenburg, 431 83 Mölndal, Sweden
| | - Daniele Leonori
- Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen, Germany
| | - Mateusz P Plesniak
- Medicinal Chemistry, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca Gothenburg, 431 83 Mölndal, Sweden
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9
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Wang Y, Fan S, Tang X. Nucleophilic Organocatalyst for Photochemical Carbon Radical Generation via S N2 Substitution. Org Lett 2024; 26:4002-4007. [PMID: 38691539 DOI: 10.1021/acs.orglett.4c01278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2024]
Abstract
Photochemical generation of radicals is a powerful way to construct various molecules. But most of these methods rely on initiators or the redox properties of radical precursors. Herein, we report a photochemical organic catalyst that reacts with benzyl halide to generate carbon radical via an SN2 pathway. This nucleophilic catalyst can be easily prepared and is bench-stable. The SN2 process does not rely on the redox properties of halides, showing potential synthetic utility. Control experiments and UV-vis spectroscopic analysis indicate that the SN2 substitution adduct is the key intermediate.
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Affiliation(s)
- Yuzhuo Wang
- Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China
| | - Shiwen Fan
- Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China
| | - Xinjun Tang
- Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China
- Zhejiang Institute, China University of Geosciences, Hangzhou 311305, China
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10
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Kweon J, Park B, Kim D, Chang S. Decarboxylative stereoretentive C-N coupling by harnessing aminating reagent. Nat Commun 2024; 15:3788. [PMID: 38710673 DOI: 10.1038/s41467-024-48075-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Accepted: 04/15/2024] [Indexed: 05/08/2024] Open
Abstract
In recent decades, strategies involving transition-metal catalyzed carbon-carbon or carbon-heteroatom bond coupling have emerged as potent synthetic tools for constructing intricate molecular architectures. Among these, decarboxylative carbon-nitrogen bond formation using abundant carboxylic acids or their derivatives has garnered notable attention for accessing alkyl- or arylamines, one of key pharmacophores. While several decarboxylative amination methods have been developed, the involvement of a common carboradical intermediate currently poses challenges in achieving stereospecific transformation toward chiral alkylamines. Herein, we present a base-mediated, stereoretentive decarboxylative amidation by harnessing 1,4,2-dioxazol-5-one as a reactive and robust amidating reagent under transition-metal-free ambient conditions, encompassing all types of primary, secondary and tertiary carboxylic acids, thereby providing access to the important pharmacophore, α-chiral amines. This method exhibits high functional group tolerance, convenient scalability, and ease of applicability for 15N-isotope labeling, thus accentuating its synthetic utilities. Experimental and computational mechanistic investigations reveal a sequence of elementary steps: i) nucleophilic addition of carboxylate to dioxazolone, ii) rearrangement to form a dicarbonyl N-hydroxy intermediate, iii) conversion to hydroxamate, followed by a Lossen-type rearrangement, and finally, iv) reaction of the in situ generated isocyanate with carboxylate leading to C-N bond formation in a stereoretentive manner.
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Affiliation(s)
- Jeonguk Kweon
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon, 34141, South Korea
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, South Korea
| | - Bumsu Park
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, South Korea
| | - Dongwook Kim
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon, 34141, South Korea
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, South Korea
| | - Sukbok Chang
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon, 34141, South Korea.
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, South Korea.
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11
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Zeng L, Xu CH, Zou XY, Sun Q, Hu M, Ouyang XH, He DL, Li JH. Iodoarene-directed photoredox β-C(sp 3)-H arylation of 1-( o-iodoaryl)alkan-1-ones with cyanoarenes via halogen atom transfer and hydrogen atom transfer. Chem Sci 2024; 15:6522-6529. [PMID: 38699280 PMCID: PMC11062093 DOI: 10.1039/d3sc06637a] [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: 12/10/2023] [Accepted: 03/25/2024] [Indexed: 05/05/2024] Open
Abstract
Site selective functionalization of inert remote C(sp3)-H bonds to increase molecular complexity offers vital potential for chemical synthesis and new drug development, thus it has been attracting ongoing research interest. In particular, typical β-C(sp3)-H arylation methods using chelation-assisted metal catalysis or metal-catalyzed oxidative/photochemical in situ generated allyl C(sp3)-H bond processes have been well developed. However, radical-mediated direct β-C(sp3)-H arylation of carbonyls remains elusive. Herein, we describe an iodoarene-directed photoredox β-C(sp3)-H arylation of 1-(o-iodoaryl)alkan-1-ones with cyanoarenes via halogen atom transfer (XAT) and hydrogen atom transfer (HAT). The method involves diethylaminoethyl radical-mediated generation of an aryl radical intermediate via XAT, then directed 1,5-HAT to form the remote alkyl radical intermediate and radical-radical coupling with cyanoarenes, and is applicable to a broad scope of unactivated remote C(sp3)-H bonds like β-C(sp3)-H bonds of o-iodoaryl-substituted alkanones and α-C(sp3)-H bonds of o-iodoarylamides. Experimental findings are supported by computational studies (DFT calculations), revealing that this method operates via a radical-relay stepwise mechanism involving multiple SET, XAT, 1,5-HAT and radical-radical coupling processes.
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Affiliation(s)
- Liang Zeng
- 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
| | - Chong-Hui Xu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University Changsha 410082 China
| | - Xiu-Yuan Zou
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University Nanchang 330063 China
| | - Qing Sun
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University Nanchang 330063 China
| | - Ming Hu
- 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
| | - Xuan-Hui Ouyang
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University Nanchang 330063 China
| | - De-Liang He
- 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
- State Key Laboratory Base of Eco-Chemical Engineering, College of Chemical Engineering, Qingdao University of Science and Technology Qingdao 266042 China
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou 730000 China
- School of Chemistry and Chemical Engineering, Henan Normal University Xinxiang Henan 475004 China
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12
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Lu YN, Che C, Zhen G, Chang X, Dong XQ, Wang CJ. Visible-light-enabled stereoselective synthesis of functionalized cyclohexylamine derivatives via [4 + 2] cycloadditions. Chem Sci 2024; 15:6507-6514. [PMID: 38699278 PMCID: PMC11062095 DOI: 10.1039/d4sc00667d] [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: 01/28/2024] [Accepted: 03/26/2024] [Indexed: 05/05/2024] Open
Abstract
An unprecedented intermolecular [4 + 2] cycloaddition of benzocyclobutylamines with α-substituted vinylketones, enabled by photoredox catalysis, has been developed. The current method enables facile access to highly functionalized cyclohexylamine derivatives that were otherwise inaccessible, in moderate to good yields with excellent diastereoselectivities. This protocol has some excellent features, such as full atom economy, good functional-group compatibility, mild reaction conditions, and an overall redox-neutral process. Additionally, an asymmetric version of this cycloaddition was preliminarily investigated via the incorporation of a chiral phosphoric acid (CPA), and moderate to good enantioselectivity could be effectively realized with excellent diastereoselectivity. Synthetic applications were demonstrated via a scale-up experiment and elaborations to access amino alcohol and cyclobutene derivatives. Based on the results of control experiments, a reasonable reaction mechanism was proposed to elucidate the reaction pathway.
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Affiliation(s)
- Yi-Nan Lu
- College of Chemistry and Molecular Sciences, Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education, Wuhan University Wuhan Hubei 430072 China
| | - Chao Che
- College of Chemistry and Molecular Sciences, Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education, Wuhan University Wuhan Hubei 430072 China
| | - Guangjin Zhen
- College of Chemistry and Molecular Sciences, Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education, Wuhan University Wuhan Hubei 430072 China
| | - Xin Chang
- College of Chemistry and Molecular Sciences, Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education, Wuhan University Wuhan Hubei 430072 China
| | - Xiu-Qin Dong
- College of Chemistry and Molecular Sciences, Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education, Wuhan University Wuhan Hubei 430072 China
| | - Chun-Jiang Wang
- College of Chemistry and Molecular Sciences, Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education, Wuhan University Wuhan Hubei 430072 China
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry Shanghai 230021 China
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13
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Cong F, Sun GQ, Ye SH, Hu R, Rao W, Koh MJ. A Bimolecular Homolytic Substitution-Enabled Platform for Multicomponent Cross-Coupling of Unactivated Alkenes. J Am Chem Soc 2024; 146:10274-10280. [PMID: 38568080 DOI: 10.1021/jacs.4c02284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/18/2024]
Abstract
The construction of C(sp3)-C(sp3) bonds remains one of the most difficult challenges in cross-coupling chemistry. Here, we report a photoredox/nickel dual catalytic approach that enables the simultaneous formation of two C(sp3)-C(sp3) linkages via trimolecular cross-coupling of alkenes with alkyl halides and hypervalent iodine-based reagents. The reaction harnesses a bimolecular homolytic substitution (SH2) mechanism and chemoselective halogen-atom transfer (XAT) to orchestrate the regioselective addition of electrophilic and nucleophilic alkyl radicals across unactivated alkenes without the need for a directing auxiliary. Utility is highlighted through late-stage (fluoro)alkylation and (trideutero)methylation of C═C bonds bearing different substitution patterns, offering straightforward access to drug-like molecules comprising sp3-hybridized carbon scaffolds.
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Affiliation(s)
- Fei Cong
- Department of Chemistry, National University of Singapore, 4 Science Drive 2, Republic of Singapore, 117544
| | - Guo-Quan Sun
- Department of Chemistry, National University of Singapore, 4 Science Drive 2, Republic of Singapore, 117544
| | - Si-Han Ye
- Department of Chemistry, National University of Singapore, 4 Science Drive 2, Republic of Singapore, 117544
| | - Rui Hu
- Department of Chemistry, National University of Singapore, 4 Science Drive 2, Republic of Singapore, 117544
- Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Weidong Rao
- Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Ming Joo Koh
- Department of Chemistry, National University of Singapore, 4 Science Drive 2, Republic of Singapore, 117544
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14
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Fernandes AJ, Giri R, Houk KN, Katayev D. Review and Theoretical Analysis of Fluorinated Radicals in Direct C Ar-H Functionalization of (Hetero)arenes. Angew Chem Int Ed Engl 2024; 63:e202318377. [PMID: 38282182 DOI: 10.1002/anie.202318377] [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: 01/25/2024] [Accepted: 01/26/2024] [Indexed: 01/30/2024]
Abstract
We highlight key contributions in the field of direct radical CAr- H (hetero)aromatic functionalization involving fluorinated radicals. A compilation of Functional Group Transfer Reagents and their diverse activation mechanisms leading to the release of radicals are discussed. The substrate scope for each radical is analyzed and classified into three categories according to the electronic properties of the substrates. Density functional theory computational analysis provides insights into the chemical reactivity of several fluorinated radicals through their electrophilicity and nucleophilicity parameters. Theoretical analysis of their reduction potentials also highlights the remarkable correlation between electrophilicity and oxidizing ability. It is also established that highly fluorinated radicals (e.g. ⋅OCF3) are capable of engaging in single-electron transfer (SET) processes rather than radical addition, which is in good agreement with experimental literature data. A reactivity scale, based on activation barrier of addition of these radicals to benzene is also elaborated using the high accuracy DLPNO-(U)CCSD(T) method.
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Affiliation(s)
- Anthony J Fernandes
- Department für Chemie und Biochemie, Universität Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Rahul Giri
- Department für Chemie und Biochemie, Universität Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Kendall N Houk
- Department of Chemistry and Biochemistry, University of California, 90095, Los Angeles, California, United States
| | - Dmitry Katayev
- Department für Chemie und Biochemie, Universität Bern, Freiestrasse 3, 3012, Bern, Switzerland
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15
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Lu S, Hu Z, Wang D, Xu T. Halogen-Atom Transfer Enabled Catalytic Enantioselective Coupling to Chiral Trifluoromethylated Alkynes via Dual Nickel and Photocatalysis. Angew Chem Int Ed Engl 2024:e202406064. [PMID: 38619363 DOI: 10.1002/anie.202406064] [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: 03/29/2024] [Revised: 04/14/2024] [Accepted: 04/15/2024] [Indexed: 04/16/2024]
Abstract
With halogen-atom transfer as an effective tool, a novel catalytic enantioselective protocol to generate chiral trifluoromethylated alkynes has been established by a cooperative photoredox and nickel catalysis system, providing a straightforward and modular route to access this type of product in good yields and enantioselectivities. The halogen-atom transfer process is essential for the reaction and this novel strategy offers another promising way to utilize alkyl halides with highly negative reduction potentials. It firstly expands nickel-catalyzed asymmetric reductive cross-couplings of organohalides from the traditional single-electron transfer to halogen-atom transfer.
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Affiliation(s)
- Shanya Lu
- Shanghai Key Laboratory of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, 1239 Siping Road, 200092, Shanghai, P. R. of China
| | - Zihao Hu
- Shanghai Key Laboratory of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, 1239 Siping Road, 200092, Shanghai, P. R. of China
| | - Dong Wang
- Shanghai Key Laboratory of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, 1239 Siping Road, 200092, Shanghai, P. R. of China
| | - Tao Xu
- Shanghai Key Laboratory of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, 1239 Siping Road, 200092, Shanghai, P. R. of China
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16
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Wang J, Niu K, Zhu H, Xu C, Deng C, Zhao W, Huang P, Lin H, Li D, Rosen J, Liu P, Allegretti F, Barth JV, Yang B, Björk J, Li Q, Chi L. Universal inter-molecular radical transfer reactions on metal surfaces. Nat Commun 2024; 15:3030. [PMID: 38589464 PMCID: PMC11001993 DOI: 10.1038/s41467-024-47252-1] [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: 09/13/2023] [Accepted: 03/23/2024] [Indexed: 04/10/2024] Open
Abstract
On-surface synthesis provides tools to prepare low-dimensional supramolecular structures. Traditionally, reactive radicals are a class of single-electron species, serving as exceptional electron-withdrawing groups. On metal surfaces, however, such species are affected by conduction band screening effects that may even quench their unpaired electron characteristics. As a result, radicals are expected to be less active, and reactions catalyzed by surface-stabilized radicals are rarely reported. Herein, we describe a class of inter-molecular radical transfer reactions on metal surfaces. With the assistance of aryl halide precursors, the coupling of terminal alkynes is steered from non-dehydrogenated to dehydrogenated products, resulting in alkynyl-Ag-alkynyl bonds. Dehalogenated molecules are fully passivated by detached hydrogen atoms. The reaction mechanism is unraveled by various surface-sensitive technologies and density functional theory calculations. Moreover, we reveal the universality of this mechanism on metal surfaces. Our studies enrich the on-surface synthesis toolbox and develop a pathway for producing low-dimensional organic materials.
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Affiliation(s)
- Junbo Wang
- School of Physics and Information Technology, Shaanxi Normal University, Xi'an, 710119, China
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, 215123, China
| | - Kaifeng Niu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, 215123, China
- Department of Physics, Chemistry and Biology, IFM, Linköping University, Linköping, 58183, Sweden
| | - Huaming Zhu
- School of Physics and Information Technology, Shaanxi Normal University, Xi'an, 710119, China
| | - Chaojie Xu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, 215123, China
| | - Chuan Deng
- School of Physics and Information Technology, Shaanxi Normal University, Xi'an, 710119, China
| | - Wenchao Zhao
- Physics Department E20, Technical University of Munich, James-Franck-Str. 1, 85748, Garching, Germany
| | - Peipei Huang
- School of Physics and Information Technology, Shaanxi Normal University, Xi'an, 710119, China
| | - Haiping Lin
- School of Physics and Information Technology, Shaanxi Normal University, Xi'an, 710119, China
| | - Dengyuan Li
- Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, State Key Laboratory of Chemical Engineering, School of Chemistry and Molecular Engineering, East China University of Science & Technology, Shanghai, 200237, China
| | - Johanna Rosen
- Department of Physics, Chemistry and Biology, IFM, Linköping University, Linköping, 58183, Sweden
| | - Peinian Liu
- Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, State Key Laboratory of Chemical Engineering, School of Chemistry and Molecular Engineering, East China University of Science & Technology, Shanghai, 200237, China
| | - Francesco Allegretti
- Physics Department E20, Technical University of Munich, James-Franck-Str. 1, 85748, Garching, Germany
| | - Johannes V Barth
- Physics Department E20, Technical University of Munich, James-Franck-Str. 1, 85748, Garching, Germany
| | - Biao Yang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, 215123, China.
- Physics Department E20, Technical University of Munich, James-Franck-Str. 1, 85748, Garching, Germany.
| | - Jonas Björk
- Department of Physics, Chemistry and Biology, IFM, Linköping University, Linköping, 58183, Sweden.
| | - Qing Li
- School of Physics and Information Technology, Shaanxi Normal University, Xi'an, 710119, China.
| | - Lifeng Chi
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, 215123, China.
- Department of Materials Science and Engineering, Macau University of Science and Technology, Macau, 999078, China.
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17
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Joly N, Colella A, Mendy ME, Mbaye MD, Gaillard S, Poater A, Renaud JL. Blue-Light Induced Iron-Catalyzed Synthesis of γ,δ-Unsaturated Ketones. CHEMSUSCHEM 2024; 17:e202301472. [PMID: 38010264 DOI: 10.1002/cssc.202301472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 11/24/2023] [Accepted: 11/24/2023] [Indexed: 11/29/2023]
Abstract
A visible-light-induced iron-catalyzed α-alkylation of ketones with allylic and propargylic alcohols as pro-electrophiles is reported. The diaminocyclopentadienone iron tricarbonyl complex plays a dual role by harvesting light and facilitating dehydrogenation and reduction steps without the help of any exogenous photosensitizer. γ,δ-Unsaturated ketones can now be accessed through this borrowing hydrogen methodology at room temperature. Mechanistic investigations revealed that the steric hindrance on the δ-position of either the dienone or ene-ynone intermediate is the key feature to prevent or decrease the competitive 1,6-reduction (and consequently the formation of the saturated ketone) and to favor the synthesis of a set of non-conjugated enones and ynones.
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Affiliation(s)
- Nicolas Joly
- Normandie Univ., LCMT, ENSICAEN, UNICAEN, CNRS, 6 boulevard du Maréchal Juin, 14000, Caen, France
- Departament de Química, Institut de Química Computacional i Catàlisi (IQCC), University of Girona, c/ Mª Aurèlia Capmany 69, 17003, Girona, Catalonia, Spain
| | - Alessandro Colella
- Normandie Univ., LCMT, ENSICAEN, UNICAEN, CNRS, 6 boulevard du Maréchal Juin, 14000, Caen, France
| | - Monique-Edwige Mendy
- Normandie Univ., LCMT, ENSICAEN, UNICAEN, CNRS, 6 boulevard du Maréchal Juin, 14000, Caen, France
- Université Assane Seck de Ziguinchor BP 523, Ziguinchor, Sénégal
| | | | - Sylvain Gaillard
- Normandie Univ., LCMT, ENSICAEN, UNICAEN, CNRS, 6 boulevard du Maréchal Juin, 14000, Caen, France
| | - Albert Poater
- Departament de Química, Institut de Química Computacional i Catàlisi (IQCC), University of Girona, c/ Mª Aurèlia Capmany 69, 17003, Girona, Catalonia, Spain
| | - Jean-Luc Renaud
- Normandie Univ., LCMT, ENSICAEN, UNICAEN, CNRS, 6 boulevard du Maréchal Juin, 14000, Caen, France
- Sorbonne Université, CNRS, Institut Parisien de Chimie Moléculaire, UMR 8232, 75005, Paris, France
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18
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Tripathy A, Bisoyi A, P A, Venugopal S, Yatham VR. Synergistic Merger of Ketone, Halogen Atom Transfer (XAT), and Nickel-Mediated C(sp 3)-C(sp 2) Cross-Electrophile Coupling Enabled by Light. ACS ORGANIC & INORGANIC AU 2024; 4:229-234. [PMID: 38585508 PMCID: PMC10996044 DOI: 10.1021/acsorginorgau.3c00062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 11/30/2023] [Accepted: 12/01/2023] [Indexed: 04/09/2024]
Abstract
In the present manuscript, we have developed a unique catalytic system by merging photoexcited ketone catalysis, halogen atom transfer (XAT), and nickel catalysis to forge C(sp3)-C(sp2) cross-electrophile coupling products from unactivated iodoalkanes and (hetero)aryl bromides. The synergistic catalytic system works under mild reaction conditions and tolerates a variety of functional groups; moreover, this strategy allows the late-stage modification of medicinally relevant molecules. Preliminary mechanistic studies reveal the role of the α-aminoalkyl radical, which further participates in the XAT process with alkyl iodides to generate the desired alkyl radical, which eventually intercepts with the nickel catalytic cycle to liberate the products in good to excellent yields.
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Affiliation(s)
- Alisha
Rani Tripathy
- School
of Chemistry, Indian Institute of Science
Education and Research, Thiruvananthapuram 695551, India
| | - Akash Bisoyi
- School
of Chemistry, Indian Institute of Science
Education and Research, Thiruvananthapuram 695551, India
| | - Arya P
- School
of Chemistry, Indian Institute of Science
Education and Research, Thiruvananthapuram 695551, India
| | - Sreelakshmi Venugopal
- School
of Chemistry, Indian Institute of Science
Education and Research, Thiruvananthapuram 695551, India
| | - Veera Reddy Yatham
- School
of Chemistry, Indian Institute of Science
Education and Research, Thiruvananthapuram 695551, India
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19
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Fan Y, Blenko AL, Labalme S, Lin W. Metal-Organic Layers with Photosensitizer and Pyridine Pairs Activate Alkyl Halides for Photocatalytic Heck-Type Coupling with Olefins. J Am Chem Soc 2024; 146:7936-7941. [PMID: 38477710 DOI: 10.1021/jacs.4c00258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2024]
Abstract
Photochemical generation of alkyl radicals from haloalkanes often requires strong energy input from ultraviolet light or a strong photoreductant. Haloalkanes can alternatively be activated with nitrogen-based nucleophiles through a sequential SN2 reaction and single-electron reduction to access alkyl radicals, but these two reaction steps have opposite steric requirements on the nucleophiles. Herein, we report the design of Hf12 metal-organic layers (MOLs) with iridium-based photosensitizer bridging ligands and secondary-building-unit-supported pyridines for photocatalytic alkyl radical generation from haloalkanes. By bringing the photosensitizer and pyridine pairs in proximity, the MOL catalysts allowed facile access to the pyridinium salts from SN2 reactions between haloalkanes and pyridines and at the same time enhanced electron transfer from excited photosensitizers to pyridinium salts to facilitate alkyl radical generation. Consequentially, the MOLs efficiently catalyzed Heck-type cross-coupling reactions between haloalkanes and olefinic substrates to generate functionalized alkenes. The MOLs showed 4.6 times higher catalytic efficiency than the homogeneous counterparts and were recycled and reused without a loss of catalytic activity.
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Affiliation(s)
- Yingjie Fan
- Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, United States
| | - Abigail L Blenko
- Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, United States
| | - Steven Labalme
- Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, United States
| | - Wenbin Lin
- Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, United States
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20
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Hossain MM, Shaikh AC, Kaur R, Gianetti TL. Red Light-Blue Light Chromoselective C(sp 2)-X Bond Activation by Organic Helicenium-Based Photocatalysis. J Am Chem Soc 2024; 146:7922-7930. [PMID: 38498938 DOI: 10.1021/jacs.3c13380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
Chromoselective bond activation has been achieved in organic helicenium (nPr-DMQA+)-based photoredox catalysis. Consequently, control over chromoselective C(sp2)-X bond activation in multihalogenated aromatics has been demonstrated. nPr-DMQA+ can only initiate the halogen atom transfer (XAT) pathway under red light irradiation to activate low-energy-accessible C(sp2)-I bonds. In contrast, blue light irradiation initiates consecutive photoinduced electron transfer (conPET) to activate more challenging C(sp2)-Br bonds. Comparative reaction outcomes have been demonstrated in the α-arylation of cyclic ketones with red and blue lights. Furthermore, red-light-mediated selective C(sp2)-I bonds have been activated in iodobromoarenes to keep the bromo functional handle untouched. Finally, the strength of the chromoselective catalysis has been highlighted with two-fold functionalization using both photo-to-transition metal and photo-to-photocatalyzed transformations.
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Affiliation(s)
- Md Mubarak Hossain
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721, United States
| | - Aslam C Shaikh
- Department of Chemistry, Indian Institute of Technology Ropar, Rupnagar, Punjab 140001, India
| | - Ramandeep Kaur
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721, United States
| | - Thomas L Gianetti
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721, United States
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21
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Zeng L, Ren HZ, Lv GF, Ouyang XH, He DL, Li JH. Electroreductive Remote Benzylic C(sp 3)-H Arylation of Aliphatic Ethers Using Cyanoarenes for the Synthesis of α-(Hetero)aryl Ethers. Org Lett 2024. [PMID: 38502576 DOI: 10.1021/acs.orglett.4c00615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
An iodoarene-driven electroreductive remote C(sp3)-H arylation of unsymmetrical 1-(o-iodoaryl)alkyl ethers with cyanoarenes for the site selective synthesis of α-(hetero)aryl ethers is developed. With the introduction of cyanoarenes as both aryl sources and electron transfer mediators, this method includes an iodoarene-driven strategy to enable the regiocontrollable formation of two new bonds, one C(sp2)-H bond, and one C(sp2)-C(sp3) bond, in a single reaction step through the sequence of halogen atom transfer (XAT), hydrogen atom transfer (HAT), radical-radical coupling, and decyanation.
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Affiliation(s)
- Liang Zeng
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, China
- State Key Laboratory Base of Eco-Chemical Engineering, College of Chemistry and Molecular Engineering, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, China
| | - Hua-Zhan Ren
- State Key Laboratory Base of Eco-Chemical Engineering, College of Chemistry and Molecular Engineering, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
| | - Gui-Fen Lv
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, China
| | - Xuan-Hui Ouyang
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, China
| | - De-Liang He
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, China
| | - Jin-Heng Li
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, China
- State Key Laboratory Base of Eco-Chemical Engineering, College of Chemistry and Molecular Engineering, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, China
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
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22
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Glogowski MP, Cercizi N, Lynch-Colameta T, Ridgers LH, Phelan JP, Rowley AM, Rauch MP. Utilization of High-Throughput Experimentation (HTE) and ChemBeads Toward the Development of an Aryl Bromide and Benzyl Bromide Photoredox Cross-Electrophile Coupling. Org Lett 2024. [PMID: 38498905 DOI: 10.1021/acs.orglett.4c00577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
The discussion herein describes a metallaphotoredox reaction that allows for efficient exploration of benzyl structure-activity relationships in medicinal chemistry. The use of HTE (high-throughput experimentation) and ChemBeads allows for rapid reaction optimization. The formation of di(hetero)arylmethanes via cross-electrophile coupling between aryl bromides and benzyl bromides provides access to diverse chemical space. The breadth of the substrate scope will be discussed, along with the utilization of batch photochemistry for the preparation of this di(hetero)arylmethane motif on a larger scale.
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Affiliation(s)
- Michal P Glogowski
- GSK, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
| | - Noel Cercizi
- GSK, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
| | - Tessa Lynch-Colameta
- GSK, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
| | - Lance H Ridgers
- GSK, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
| | - James P Phelan
- GSK, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
| | - Ann M Rowley
- GSK, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
| | - Martin P Rauch
- GSK, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
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23
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Li W, Huang Z, Zhong D, Li H. Photocatalyst-Free Activation of Sulfamoyl Chlorides for Regioselective Sulfamoyl-Oximation of Alkenes via Hydrogen Atom Transfer (HAT) and Halogen-Atom Transfer (XAT) Relay Strategy. Org Lett 2024; 26:2062-2067. [PMID: 38451173 DOI: 10.1021/acs.orglett.4c00314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2024]
Abstract
The use of readily available and diverse sulfamoyl chlorides for synthesizing sulfonamide compounds presents an intriguing, yet significantly underexplored strategy. Activating sulfamoyl chlorides via single-electron reduction poses challenges due to their high reduction potential. Alternatively, the SO2-Cl bond in sulfamoyl chlorides could be readily cleaved by XAT. However, the existing methodologies have been limited to either the use of photocatalyst or the monofunctionalization of activated alkenes. Here, we report a regioselective sulfamoyl-oximation of alkenes by involving the activation of sulfamoyl chlorides through a HAT and XAT relay strategy in a photocatalyst-free way. The key to this success lies in the dual roles of tert-butyl nitrite (TBN), which not only serves as the source of oximes but also acts as the HAT reagent to generate the crucial XAT reactive species. The exclusion of metal catalysts or photosensitizers for utilizing light energy renders this protocol versatile and universally applicable for synthesizing a broad range of structurally diverse oxime-containing alkyl sulfonamides.
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Affiliation(s)
- Wei Li
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China
| | - Zhihua Huang
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China
| | - Deliang Zhong
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China
| | - Huaifeng Li
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China
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24
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Zhu J, Wang R, Ma Z, Zuo W, Zhu M. Unleashing the Power of PET-RAFT Polymerization: Journey from Porphyrin-Based Photocatalysts to Combinatorial Technologies and Advanced Bioapplications. Biomacromolecules 2024; 25:1371-1390. [PMID: 38346318 DOI: 10.1021/acs.biomac.3c01356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
The emergence of photoinduced energy/electron transfer-reversible addition-fragmentation chain transfer polymerization (PET-RAFT) not only revolutionized the field of photopolymerization but also accelerated the development of porphyrin-based photocatalysts and their analogues. The continual expansion of the monomer family compatible with PET-RAFT polymerization enhances the range of light radiation that can be harnessed, providing increased flexibility in polymerization processes. Furthermore, the versatility of PET-RAFT polymerization extends beyond its inherent capabilities, enabling its integration with various technologies in diverse fields. This integration holds considerable promise for the advancement of biomaterials with satisfactory bioapplications. As researchers delve deeper into the possibilities afforded by PET-RAFT polymerization, the collaborative efforts of individuals from diverse disciplines will prove invaluable in unleashing its full potential. This Review presents a concise introduction to the fundamental principles of PET-RAFT, outlines the progress in photocatalyst development, highlights its primary applications, and offers insights for future advancements in this technique, paving the way for exciting innovations and applications.
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Affiliation(s)
- Jiaoyang Zhu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, 2999 North Renmin Road, Shanghai 201620, China
| | - Ruili Wang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, 2999 North Renmin Road, Shanghai 201620, China
| | - Zhiyuan Ma
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, 2999 North Renmin Road, Shanghai 201620, China
| | - Weiwei Zuo
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, 2999 North Renmin Road, Shanghai 201620, China
| | - Meifang Zhu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, 2999 North Renmin Road, Shanghai 201620, China
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25
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Zhu WF, Empel C, Pelliccia S, Koenigs RM, Proschak E, Hernandez-Olmos V. Photochemistry in Medicinal Chemistry and Chemical Biology. J Med Chem 2024. [PMID: 38457829 DOI: 10.1021/acs.jmedchem.3c02109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/10/2024]
Abstract
Photochemistry has emerged as a transformative force in organic chemistry, significantly expanding the chemical space accessible for medicinal chemistry. Light-induced reactions enable the efficient synthesis of intricate organic structures and have found applications throughout the different stages of the drug discovery and development processes. Moreover, photochemical techniques provide innovative solutions in chemical biology, allowing precise spatiotemporal drug activation and targeted delivery. In this Perspective, we highlight the already numerous remarkable applications and the even more promising future of photochemistry in medicinal chemistry and chemical biology.
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Affiliation(s)
- W Felix Zhu
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt am Main, Germany
| | - Claire Empel
- RWTH Aachen University, Institute of Organic Chemistry, Landoltweg 1, D-52074 Aachen, Germany
| | - Sveva Pelliccia
- Department of Pharmacy (DoE 2023-2027), University of Naples Federico II, via D. Montesano 49, 80131 Naples, Italy
| | - Rene M Koenigs
- RWTH Aachen University, Institute of Organic Chemistry, Landoltweg 1, D-52074 Aachen, Germany
| | - Ewgenij Proschak
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt am Main, Germany
- Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, Theodor-Stern-Kai 7, 60596 Frankfurt am Main, Germany
| | - Victor Hernandez-Olmos
- Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, Theodor-Stern-Kai 7, 60596 Frankfurt am Main, Germany
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26
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De Jesus IS, Vélez JAC, Pissinati EF, Correia JTM, Rivera DG, Paixao MW. Recent Advances in Photoinduced Modification of Amino Acids, Peptides, and Proteins. CHEM REC 2024; 24:e202300322. [PMID: 38279622 DOI: 10.1002/tcr.202300322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 12/01/2023] [Indexed: 01/28/2024]
Abstract
The chemical modification of biopolymers like peptides and proteins is a key technology to access vaccines and pharmaceuticals. Similarly, the tunable derivatization of individual amino acids is important as they are key building blocks of biomolecules, bioactive natural products, synthetic polymers, and innovative materials. The high diversity of functional groups present in amino acid-based molecules represents a significant challenge for their selective derivatization Recently, visible light-mediated transformations have emerged as a powerful strategy for achieving chemoselective biomolecule modification. This technique offers numerous advantages over other methods, including a higher selectivity, mild reaction conditions and high functional-group tolerance. This review provides an overview of the most recent methods covering the photoinduced modification for single amino acids and site-selective functionalization in peptides and proteins under mild and even biocompatible conditions. Future challenges and perspectives are discussed beyond the diverse types of photocatalytic transformations that are currently available.
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Affiliation(s)
- Iva S De Jesus
- Laboratory for Sustainable Organic Synthesis and Catalysis, Department of Chemistry, Federal University of São Carlos - UFSCar, São Carlos, São Paulo, 13565-905, Brazil
| | - Jeimy A C Vélez
- Laboratory for Sustainable Organic Synthesis and Catalysis, Department of Chemistry, Federal University of São Carlos - UFSCar, São Carlos, São Paulo, 13565-905, Brazil
| | - Emanuele F Pissinati
- Laboratory for Sustainable Organic Synthesis and Catalysis, Department of Chemistry, Federal University of São Carlos - UFSCar, São Carlos, São Paulo, 13565-905, Brazil
| | - Jose Tiago M Correia
- Laboratory for Sustainable Organic Synthesis and Catalysis, Department of Chemistry, Federal University of São Carlos - UFSCar, São Carlos, São Paulo, 13565-905, Brazil
| | - Daniel G Rivera
- Laboratory of Synthetic and Biomolecular Chemistry, Faculty of Chemistry, University of Havana Zapata & G, Havana, 10400, Cuba
| | - Márcio W Paixao
- Laboratory for Sustainable Organic Synthesis and Catalysis, Department of Chemistry, Federal University of São Carlos - UFSCar, São Carlos, São Paulo, 13565-905, Brazil
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27
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Griffiths OM, Esteves HA, Emmet DC, Ley SV. Photoredox-Catalyzed Preparation of Sulfones Using Bis-Piperidine Sulfur Dioxide - An Underutilized Reagent for SO 2 Transfer. Chemistry 2024; 30:e202303976. [PMID: 38116896 DOI: 10.1002/chem.202303976] [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: 11/29/2023] [Revised: 12/15/2023] [Accepted: 12/18/2023] [Indexed: 12/21/2023]
Abstract
Sulfonyl groups are widely observed in biologically relevant molecules and consequently, SO2 capture is an increasingly attractive method to prepare these sulfonyl-containing compounds given the range of SO2 -surrogates now available as alternatives to using the neat gas. This, along with the advent of photoredox catalysis, has enabled mild radical capture of SO2 to emerge as an effective route to sulfonyl compounds. Here we report a photoredox-catalyzed cross-electrophile sulfonylation of aryl and alkyl bromides making use of a previously under-used amine-SO2 surrogate; bis(piperidine) sulfur dioxide (PIPSO). A broad selection of alkyl and aryl bromides were photocatalytically converted to their corresponding sulfinates and then trapped with various electrophiles in a one-pot multistep procedure to prepare sulfones and sulfonamides.
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Affiliation(s)
- Oliver M Griffiths
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, Cambridge, UK
| | - Henrique A Esteves
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, Cambridge, UK
| | - Darcy C Emmet
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, Cambridge, UK
| | - Steven V Ley
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, Cambridge, UK
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28
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Maust MC, Blakey SB. Photoredox-Driven Three-Component Coupling of Aryl Halides, Olefins, and O 2. ACS Catal 2024; 14:2582-2587. [PMID: 38384944 PMCID: PMC10877571 DOI: 10.1021/acscatal.3c05988] [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: 12/09/2023] [Revised: 01/19/2024] [Accepted: 01/22/2024] [Indexed: 02/23/2024]
Abstract
Modern organic synthesis requires methodologies that bring together abundant feedstock chemicals in a mild and efficient manner. To aid in this effort, we have developed a multicomponent radical hydroxyarylation reaction that utilizes aryl halides, olefins, and O2 as the reaction components. Crucial to this advance was an oxidative, rather than a reductive, approach to aryl radical generation, which enables reaction tolerance to O2. This methodology displays a broad functional group tolerance with a variety of functionalized aryl halides and a broad array of olefins. Development of this methodology enables rapid access to biologically relevant hydroxyaryl products from simple, commercially available starting materials.
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Affiliation(s)
- Mark C. Maust
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
| | - Simon B. Blakey
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
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29
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Yu W, Wang H, Zhao K, Li W, Wang T, Fu J. Visible-Light-Induced Three-Component 1,2-Alkylpyridylation of Alkenes via a Halogen-Atom Transfer Process. J Org Chem 2024; 89:1703-1708. [PMID: 38227772 DOI: 10.1021/acs.joc.3c02388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
Visible-light-induced three-component 1,2-alkylpyridylation of alkenes with unactivated alkyl iodides and aryl cyanides is reported via a photocatalytic halogen-atom transfer (XAT) strategy. This metal-free protocol utilizes readily available tertiary alkylamine as the terminal reductant to smoothly convert alkyl iodides into the corresponding carbon radical species. The reaction features a broad substrate scope, excellent functional group tolerance, high efficiency, and mild reaction conditions. The practicability of this methodology is further demonstrated in the late-stage difunctionalization of bioactive molecules.
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Affiliation(s)
- Weijie Yu
- National Research Center for Carbohydrate Synthesis, Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education and Jiangxi Province Key Laboratory of Chemical Biology, Jiangxi Normal University, Nanchang 330022, China
| | - Hongyu Wang
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Department of Chemistry, Northeast Normal University, Changchun 130024, China
| | - Kuang Zhao
- National Research Center for Carbohydrate Synthesis, Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education and Jiangxi Province Key Laboratory of Chemical Biology, Jiangxi Normal University, Nanchang 330022, China
| | - Wendong Li
- National Research Center for Carbohydrate Synthesis, Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education and Jiangxi Province Key Laboratory of Chemical Biology, Jiangxi Normal University, Nanchang 330022, China
| | - Tao Wang
- National Research Center for Carbohydrate Synthesis, Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education and Jiangxi Province Key Laboratory of Chemical Biology, Jiangxi Normal University, Nanchang 330022, China
| | - Junkai Fu
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Department of Chemistry, Northeast Normal University, Changchun 130024, China
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30
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Chatgilialoglu C, Barata-Vallejo S, Gimisis T. Radical Reactions in Organic Synthesis: Exploring in-, on-, and with-Water Methods. Molecules 2024; 29:569. [PMID: 38338314 PMCID: PMC10856544 DOI: 10.3390/molecules29030569] [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: 12/19/2023] [Revised: 01/18/2024] [Accepted: 01/19/2024] [Indexed: 02/12/2024] Open
Abstract
Radical reactions in water or aqueous media are important for organic synthesis, realizing high-yielding processes under non-toxic and environmentally friendly conditions. This overview includes (i) a general introduction to organic chemistry in water and aqueous media, (ii) synthetic approaches in, on, and with water as well as in heterogeneous phases, (iii) reactions of carbon-centered radicals with water (or deuterium oxide) activated through coordination with various Lewis acids, (iv) photocatalysis in water and aqueous media, and (v) synthetic applications bioinspired by naturally occurring processes. A wide range of chemical processes and synthetic strategies under different experimental conditions have been reviewed that lead to important functional group translocation and transformation reactions, leading to the preparation of complex molecules. These results reveal how water as a solvent/medium/reagent in radical chemistry has matured over the last two decades, with further discoveries anticipated in the near future.
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Affiliation(s)
- Chryssostomos Chatgilialoglu
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy
- Center of Advanced Technologies, Adam Mickiewicz University, 61-712 Poznan, Poland
| | - Sebastian Barata-Vallejo
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy
- Facultad de Farmacia y Bioquímica, Departamento de Ciencias Químicas, Universidad de Buenos Aires, Junin 954, Buenos Aires CP 1113, Argentina
| | - Thanasis Gimisis
- Department of Chemistry, National and Kapodistrian University of Athens, 15771 Athens, Greece
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31
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Geniller L, Taillefer M, Jaroschik F, Prieto A. Photocatalyzed Amination of Alkyl Halides to Access Primary Amines. J Org Chem 2024; 89:656-664. [PMID: 38061988 DOI: 10.1021/acs.joc.3c02431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2024]
Abstract
We demonstrate that oxime ester derivatives can be used as both a halogen atom transfer (XAT) agent and an imine source under photocatalytic conditions, allowing the radical amination of alkyl halides, resulting in the formation of a broad scope of imines. Hydrolysis of the latter gives direct access to the corresponding primary amines. Mechanistically, the reaction is believed to proceed through the formation of aryl radical intermediates, which are responsible for the activation of alkyl halides via XAT.
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Affiliation(s)
- Lilian Geniller
- ICGM, Univ Montpellier, CNRS, ENSCM, 34000 Montpellier, France
| | - Marc Taillefer
- ICGM, Univ Montpellier, CNRS, ENSCM, 34000 Montpellier, France
| | | | - Alexis Prieto
- ICGM, Univ Montpellier, CNRS, ENSCM, 34000 Montpellier, France
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32
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Zhang TB, Wang F, Ouyang JY, Luo ZW, Qin JH, Li JH, Ouyang XH. Aryldiazonium-Salt-Triggered Carboxylative Azotization of Pyrroles or Indoles with Polyhalomethanes via Halogen-Atom Transfer (XAT). Org Lett 2024. [PMID: 38175821 DOI: 10.1021/acs.orglett.3c03701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2024]
Abstract
A halogen-atom-transfer (XAT)-based method for carbonylazotization of pyrroles or indoles with aryldiazonium salts and polyhalomethanes via dual C(sp2)-H bond functionalization is described. Using aryldiazonium salts realizes carbonylation/azotization of pyrroles or indoles via polyhalomethyl-radical-mediated and electrophilic substitution, thus providing a green, efficient, and step-economy approach for synthesis of multifunctional pyrroles or indoles from the easily available substrates. Notably, this strategy relies on the use of aryldiazonium salts to extend the well-established iodine atom transfer to bromine or chlorine atom transfer.
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Affiliation(s)
- Tian-Bao Zhang
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, China
| | - Fang Wang
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, China
| | - Jun-Yao Ouyang
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, China
| | - Zhen-Wei Luo
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, China
| | - Jing-Hao Qin
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, China
| | - Jin-Heng Li
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, China
- State Key Laboratory Base of Eco-Chemical Engineering, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Xuan-Hui Ouyang
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, China
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33
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Tian X, Liu Y, Yakubov S, Schütte J, Chiba S, Barham JP. Photo- and electro-chemical strategies for the activations of strong chemical bonds. Chem Soc Rev 2024; 53:263-316. [PMID: 38059728 DOI: 10.1039/d2cs00581f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2023]
Abstract
The employment of light and/or electricity - alternatively to conventional thermal energy - unlocks new reactivity paradigms as tools for chemical substrate activations. This leads to the development of new synthetic reactions and a vast expansion of chemical spaces. This review summarizes recent developments in photo- and/or electrochemical activation strategies for the functionalization of strong bonds - particularly carbon-heteroatom (C-X) bonds - via: (1) direct photoexcitation by high energy UV light; (2) activation via photoredox catalysis under irradiation with relatively lower energy UVA or blue light; (3) electrochemical reduction; (4) combination of photocatalysis and electrochemistry. Based on the types of the targeted C-X bonds, various transformations ranging from hydrodefunctionalization to cross-coupling are covered with detailed discussions of their reaction mechanisms.
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Affiliation(s)
- Xianhai Tian
- Fakultät für Chemie und Pharmazie, Universität Regensburg, 93040 Regensburg, Germany.
| | - Yuliang Liu
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637371, Singapore.
| | - Shahboz Yakubov
- Fakultät für Chemie und Pharmazie, Universität Regensburg, 93040 Regensburg, Germany.
| | - Jonathan Schütte
- Fakultät für Chemie und Pharmazie, Universität Regensburg, 93040 Regensburg, Germany.
| | - Shunsuke Chiba
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637371, Singapore.
| | - Joshua P Barham
- Fakultät für Chemie und Pharmazie, Universität Regensburg, 93040 Regensburg, Germany.
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34
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Ioannou DI, Capaldo L, Sanramat J, Reek JNH, Noël T. Accelerated Electrophotocatalytic C(sp 3 )-H Heteroarylation Enabled by an Efficient Continuous-Flow Reactor. Angew Chem Int Ed Engl 2023; 62:e202315881. [PMID: 37972351 DOI: 10.1002/anie.202315881] [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: 10/20/2023] [Revised: 11/13/2023] [Accepted: 11/16/2023] [Indexed: 11/19/2023]
Abstract
Electrophotocatalytic transformations are garnering attention in organic synthesis, particularly for accessing reactive intermediates under mild conditions. Moving these methodologies to continuous-flow systems, or flow ElectroPhotoCatalysis (f-EPC), showcases potential for scalable processes due to enhanced irradiation, increased electrode surface, and improved mixing of the reaction mixture. Traditional methods sequentially link photochemical and electrochemical reactions, using flow reactors connected in series, yet struggle to accommodate reactive transient species. In this study, we introduce a new flow reactor concept for electrophotocatalysis (EPC) that simultaneously utilizes photons and electrons. The reactor is designed with a transparent electrode and employs cost-effective materials. We used this technology to develop an efficient process for electrophotocatalytic heteroarylation of C(sp3 )-H bonds. Importantly, the same setup can also facilitate purely electrochemical and photochemical transformations. This reactor represents a significant advancement in electrophotocatalysis, providing a framework for its application in flow for complex synthetic transformations.
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Affiliation(s)
- Dimitris I Ioannou
- Flow Chemistry Group, van't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Science Park 904, 1098, XH Amsterdam, The Netherlands
- Supramolecular and Homogeneous Catalysis Group, van't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Science Park 904, 1098, XH Amsterdam, The Netherlands
| | - Luca Capaldo
- Flow Chemistry Group, van't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Science Park 904, 1098, XH Amsterdam, The Netherlands
- SynCat Lab, Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124, Parma, Italy
| | - Jiri Sanramat
- Flow Chemistry Group, van't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Science Park 904, 1098, XH Amsterdam, The Netherlands
| | - Joost N H Reek
- Supramolecular and Homogeneous Catalysis Group, van't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Science Park 904, 1098, XH Amsterdam, The Netherlands
| | - Timothy Noël
- Flow Chemistry Group, van't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Science Park 904, 1098, XH Amsterdam, The Netherlands
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35
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Fernández-García S, Chantzakou VO, Juliá-Hernández F. Direct Decarboxylation of Trifluoroacetates Enabled by Iron Photocatalysis. Angew Chem Int Ed Engl 2023:e202311984. [PMID: 38088503 DOI: 10.1002/anie.202311984] [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: 08/16/2023] [Indexed: 12/30/2023]
Abstract
Trifluoroacetates are the most abundant and accessible sources of trifluoromethyl groups, which are key components in pharmaceuticals and agrochemicals. The generation of trifluoromethyl reactive radicals from trifluoroacetates requires their decarboxylation, which is hampered by their high oxidation potential. This constitutes a major challenge for redox-based methods, because of the need to pair the redox potentials with trifluoroacetate. Here we report a strategy based on iron photocatalysis to promote the direct photodecarboxylation of trifluoroacetates that displays reactivity features that escape from redox limitations. Our synthetic design has enabled the use of trifluoroacetates for the trifluoromethylation of more easily oxidizable organic substrates, offering new opportunities for late-stage derivatization campaigns using chemical feedstocks, Earth-abundant catalysts, and visible-light.
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Affiliation(s)
- Sara Fernández-García
- Departamento de Química Inorgánica, Facultad de Química, Universidad de Murcia, Campus de Espinardo, 30100, Murcia, Spain
| | - Veronika O Chantzakou
- Departamento de Química Inorgánica, Facultad de Química, Universidad de Murcia, Campus de Espinardo, 30100, Murcia, Spain
| | - Francisco Juliá-Hernández
- Departamento de Química Inorgánica, Facultad de Química, Universidad de Murcia, Campus de Espinardo, 30100, Murcia, Spain
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36
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Li H, Qiu X, Zhang X, Wu X. Sulfonyl Group-Induced Remote C(sp 3)-N Bond Construction through Hydrogen Atom Transfer. Org Lett 2023. [PMID: 38054933 DOI: 10.1021/acs.orglett.3c03401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
This work demonstrates sulfonyl group-induced remote C(sp3)-N bond construction using a strategy of merging aryl radical-mediated halogen atom transfer and intramolecularly regioselective hydrogen atom transfer (HAT). A plethora of aliphatic sulfones, sulfonamides, and sulfonates are amenable and undergo regioselective C(sp3)-H amination by utilizing an iron salt at room temperature. This protocol involves iodine atom transfer, a HAT process enabled by an alkyl radical adjacent to a sulfonyl group, and amination mediated by an aryl diazonium salt.
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Affiliation(s)
- 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
| | - Xiancheng Qiu
- 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
| | - Xu 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
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37
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Wu X, Gao B. Hydrosulfonylation of Unactivated Alkenes and Alkynes by Halogen-Atom Transfer (XAT) Cleavage of S VI-F Bond. Org Lett 2023. [PMID: 38019153 DOI: 10.1021/acs.orglett.3c03628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2023]
Abstract
A photochemical halogen-atom transfer (XAT) method for generating sulfonyl radicals from aryl sulfonyl fluorides has been developed. It allows the hydrosulfonylation of unactivated alkenes, which was challenging to achieve through our previous single-electron transfer route. This reaction has excellent functional group tolerance and substrate scope under mild conditions.
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Affiliation(s)
- Xing Wu
- State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Bing Gao
- State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
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38
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Liang F, Chen N, Cheng K, Wang Q. N-Heterocyclic Carbene and Manganese Synergistic Catalysis: A Three-Component Radical Acylmonofluoroalkylation of Alkenes. Org Lett 2023; 25:8168-8172. [PMID: 37922199 DOI: 10.1021/acs.orglett.3c03461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2023]
Abstract
Despite the importance of monofluoroalkyl groups in pharmaceutically relevant molecules, catalytic protocols for their incorporation into alkenes remain limited. We describe herein a three-component acylmonofluoroalkylation of alkenes for the introduction of such moieties through an unprecedented cooperativity between the N-heterocyclic carbene catalyst and earth-abundant Mn(II) complex. This general method can be applied to a variety of alkenes, including styrenes, 1,3-enynes, and allenes, as well as complex substrates containing natural product and drug motifs.
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Affiliation(s)
- Feng Liang
- School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, Guangxi, P. R. China
| | - Ning Chen
- School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, Guangxi, P. R. China
| | - Keguang Cheng
- School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, Guangxi, P. R. China
| | - Quande Wang
- School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, Guangxi, P. R. China
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39
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Arkhypchuk AI, Tran TT, Charaf R, Hammarström L, Ott S. Mechanistic Insights and Synthetic Explorations of the Photoredox-Catalyzed Activation of Halophosphines. Inorg Chem 2023; 62:18391-18398. [PMID: 37853683 PMCID: PMC10647117 DOI: 10.1021/acs.inorgchem.3c01946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Indexed: 10/20/2023]
Abstract
The light-driven activation of halophosphines R2PX (R = alkyl- or aryl, X = Cl, Br) by an IrIII-based photocatalyst is described. It is shown that initially formed secondary phosphines R2PH react readily with the remaining R2PX in a parent-child reaction to form diphosphines R2P-PR2. Aryl-containing diphosphines can be further reduced to secondary phosphines RAr2PH under identical photoredox conditions. Dihalophosphines RPX2 are also activated by the photoredox protocol, giving rise to unusual 3-, 4-, and 5-membered cyclophosphines. Transient absorption studies show that the excited state of the Ir photocatalyst is reductively quenched by the DIPEA (N,N-di-iso-propylethylamine) electron donor. Electron transfer to R2PX is however unexpectedly slow and cannot compete with recombination with the oxidized donor DIPEA•+. As DIPEA is not a perfectly reversible donor, a small proportion of the total IrII population escapes recombination, providing the reductant for the observed transformations.
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Affiliation(s)
- Anna I. Arkhypchuk
- Department of Chemistry—Ångström, Laboratory Uppsala University, P.O. Box 523, 751 20 Uppsala, Sweden
| | - Thuan T. Tran
- Department of Chemistry—Ångström, Laboratory Uppsala University, P.O. Box 523, 751 20 Uppsala, Sweden
| | - Rima Charaf
- Department of Chemistry—Ångström, Laboratory Uppsala University, P.O. Box 523, 751 20 Uppsala, Sweden
| | - Leif Hammarström
- Department of Chemistry—Ångström, Laboratory Uppsala University, P.O. Box 523, 751 20 Uppsala, Sweden
| | - Sascha Ott
- Department of Chemistry—Ångström, Laboratory Uppsala University, P.O. Box 523, 751 20 Uppsala, Sweden
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40
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Cao S, Kim D, Lee W, Hong S. Photocatalytic Enantioselective Hydrosulfonylation of α,β-Unsaturated Carbonyls with Sulfonyl Chlorides. Angew Chem Int Ed Engl 2023; 62:e202312780. [PMID: 37782249 DOI: 10.1002/anie.202312780] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 10/01/2023] [Accepted: 10/02/2023] [Indexed: 10/03/2023]
Abstract
This research explores the enantioselective hydrosulfonylation of various α,β-unsaturated carbonyl compounds via the use of visible light and redox-active chiral Ni-catalysis, facilitating the synthesis of enantioenriched α-chiral sulfones with remarkable enantioselectivity (exceeding 99 % ee). A significant challenge entails enhancing the reactivity between chiral metal-coordinated carbonyl compounds and moderate electrophilic sulfonyl radicals, aiming to minimize the background reactions. The success of our approach stems from two distinctive attributes: 1) the Cl-atom abstraction employed for sulfonyl radical generation from sulfonyl chlorides, and 2) the single-electron reduction to produce a key enolate radical Ni-complex. The latter process appears to enhance the feasibility of the sulfonyl radical's addition to the electron-rich enolate radical. An in-depth investigation into the reaction mechanism, supported by both experimental observations and theoretical analysis, offers insight into the intricate reaction process. Moreover, the versatility of our methodology is highlighted through its successful application in the late-stage functionalization of complex bioactive molecules, demonstrating its practicality as a strategy for producing α-chiral sulfones.
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Affiliation(s)
- Shi Cao
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Doyoung Kim
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Wooseok Lee
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Sungwoo Hong
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
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41
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Zhang T, Huang H. Photocatalyzed Aminomethylation of Alkyl Halides Enabled by Sterically Hindered N-Substituents. Angew Chem Int Ed Engl 2023; 62:e202310114. [PMID: 37721856 DOI: 10.1002/anie.202310114] [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: 07/16/2023] [Revised: 09/16/2023] [Accepted: 09/18/2023] [Indexed: 09/20/2023]
Abstract
The catalytic C(sp3 )-C(sp3 ) coupling of alkyl halides and tertiary amines offers a promising tool for the rapid decoration of amine skeletons. However, this approach has not been well established, partially due to the challenges in precisely distinguishing and controlling the reactivity of amine-coupling partners and their product homologues. Herein, we developed a metal-free photocatalytic system for the aminomethylation of alkyl halides through radical-involved C(sp3 )-C(sp3 ) bond formation, allowing for the synthesis of sterically congested tertiary amines that are of interest in organic synthesis but not easily prepared by other methods. Mechanistic studies disclosed that sterically hindered N-substituents are key to activate the amine coupling partners by tuning their redox potentials to drive the reaction forward.
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Affiliation(s)
- Tianze Zhang
- 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
| | - Hanmin Huang
- 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
- Key Laboratory of Green and Precise Synthetic Chemistry and Applications, Ministry of Education, Huaibei Normal University, Huaibei, 235000, P. R. China
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42
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Mörsdorf JM, Ballmann J. Coordination-Induced Radical Generation: Selective Hydrogen Atom Abstraction via Controlled Ti-C σ-Bond Homolysis. J Am Chem Soc 2023; 145:23452-23460. [PMID: 37861658 DOI: 10.1021/jacs.3c05748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2023]
Abstract
A method for the generation of transient alkyl radicals via homolytic Ti-C bond cleavage was developed by employing a tailor-made organotitanium half-cage complex. In contrast to established metal-mediated radical initiation protocols via thermal or photochemical M-C σ-bond homolysis, radical formation is triggered solely by coordination of a solvent molecule (thf) to a titanium(IV) center. During the reaction, the nonstabilized alkyl radical is formed along with a persistent titanium(III) metalloradical, thus taming the former transient radical (persistent radical effect). Radical coupling and hydrogen atom abstraction (HAT) reactions have been explored not only experimentally but also computationally and by means of kinetic analysis. Exploiting these findings led to the development of selective HAT transformations, for example, with 9,10-dihydroanthracene. Deuterium labeling studies using selectively deuterated alkyls and 9,10-dihydroanthracene-d4 confirmed a radical pathway, which was underpinned by developing a radical-radical cross-coupling reaction for transferring the alkyl radical to a stable Sn-centered radical. To set the stage for an application in organic synthesis, a 5-endo-trig radical cyclization based on our methodology was established, and a dihydroxylated sesquiterpene was thus prepared in high diastereomeric excess.
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Affiliation(s)
- Jean-Marc Mörsdorf
- Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 276, D-69120 Heidelberg, Germany
| | - Joachim Ballmann
- Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 276, D-69120 Heidelberg, Germany
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43
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Hodgson JW, Folgueiras-Amador AA, Pletcher D, Harrowven DC, Denuault G, Brown RCD. Spatio-temporal detachment of homogeneous electron transfer in controlling selectivity in mediated organic electrosynthesis. Faraday Discuss 2023; 247:302-323. [PMID: 37522856 DOI: 10.1039/d3fd00089c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/01/2023]
Abstract
In electrosynthesis, electron transfer (ET) mediators are normally chosen such that they are more easily reduced (or oxidised) than the substrate for cathodic (or anodic) processes; setting the electrode potential to the mediator therefore ensures selective heterogeneous ET with the mediator at the electrode, rather than the substrate. The current work investigates the opposite, and counter intuitive, situation for a successful mediated electroreductive process where the mediator (phenanthrene) has a reduction potential that is negative to that of the substrate, and the cathode potential is set negative to both (Eele < EM < Es). Simulations reveal a complex interplay between mass transport, the relative concentrations of the mediator and substrate as well as the heterogeneous and homogeneous rate constants for multiple steps, which under suitable conditions, leads to separation of the homogeneous chemistry in a reaction layer detached from the electrode. Reaction layer detachment is a spatio-temporal effect arising due to opposing fluxes of the mediator radical anion M˙- and the substrate 1, which ultimately prevents 1 from reaching the electrode, thereby affording a different reaction pathway. Simulations representative of unstirred batch (1D) and flow (2D) electrolysis are presented, which qualitatively reproduce the experimental selectivity outcomes for mediated and unmediated electroreductive cyclisation of aryl iodide 1. The potential to use highly reducing homogeneous ET agents, possessing reduction potentials beyond those of the substrates, offers exciting opportunities in mediated electrosynthesis.
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Affiliation(s)
- Jack W Hodgson
- School of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, UK.
| | | | - Derek Pletcher
- School of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, UK.
| | - David C Harrowven
- School of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, UK.
| | - Guy Denuault
- School of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, UK.
| | - Richard C D Brown
- School of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, UK.
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44
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Sun X, Zheng K. Electrochemical halogen-atom transfer alkylation via α-aminoalkyl radical activation of alkyl iodides. Nat Commun 2023; 14:6825. [PMID: 37884528 PMCID: PMC10603137 DOI: 10.1038/s41467-023-42566-y] [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: 05/21/2023] [Accepted: 10/16/2023] [Indexed: 10/28/2023] Open
Abstract
Alkyl halides, widely recognized as important building blocks and reagents in organic synthesis, can serve as versatile alkyl radical precursors in radical-based transformations. However, generating alkyl radicals directly from unactivated alkyl halides under mild conditions remains a challenge due to their extremely low reduction potentials. To address this issue, α-aminoalkyl radicals were employed as efficient halogen-atom transfer (XAT) reagents in the photoredox activation of unactivated alkyl halides. Here, we report an effective electrooxidation strategy for generating alkyl radicals from unactivated alkyl iodides via an electrochemical halogen-atom transfer (e-XAT) process under mild conditions. The α-aminoalkyl radicals generated by anodic oxidation are demonstrated to be efficient XAT reagents in these transformations. This facile electricity-driven strategy obviates the need for sacrificial anodes and external chemical oxidants. The method successfully applies to a wide variety of alkyl iodides, including primary, secondary, and tertiary, as well as structurally diverse olefins, exhibiting excellent functional group tolerance. Moreover, we further demonstrate the utility of this strategy by rapidly functionalizing complex molecules and biomolecules.
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Affiliation(s)
- Xiang Sun
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, PR China
| | - Ke Zheng
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, PR China.
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45
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Wang W, Yan X, Ye F, Zheng S, Huang G, Yuan W. Nickel/Photoredox Dual-Catalyzed Regiodivergent Aminoalkylation of Unactivated Alkyl Halides. J Am Chem Soc 2023; 145:23385-23394. [PMID: 37824756 DOI: 10.1021/jacs.3c09705] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
A mild and regiodivergent aminoalkylation of unactivated alkyl halides is disclosed via a dual photoredox/nickel catalysis. Bipyridyl-type ligands without an ortho-substituent control the site-selective coupling at the original position, while ortho-disubstituted ligands tune the site-selectivity at a remote, unprefunctionalized position. Mechanistic studies combined with DFT calculations give insight into the mechanism and the origins of the ligand-controlled regioselectivity. Notably, this redox-neutral, regiodivergent alkyl-alkyl coupling features mild conditions, broad substrate scope for both alkyl coupling partners, and excellent site-selectivity and offers a straightforward way for α-alkylation of tertiary amines to synthesize structurally diverse alkylamines and value-added amino acid derivatives.
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Affiliation(s)
- Wenlong Wang
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology (HUST), 1037 Luoyu Road, Wuhan 430074, People's Republic of China
| | - Xueyuan Yan
- Department of Chemistry, School of Science and Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Tianjin University, Tianjin 300072, People's Republic of China
| | - Fu Ye
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology (HUST), 1037 Luoyu Road, Wuhan 430074, People's Republic of China
| | - Songlin Zheng
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology (HUST), 1037 Luoyu Road, Wuhan 430074, People's Republic of China
| | - Genping Huang
- Department of Chemistry, School of Science and Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Tianjin University, Tianjin 300072, People's Republic of China
| | - Weiming Yuan
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology (HUST), 1037 Luoyu Road, Wuhan 430074, People's Republic of China
- Shenzhen Huazhong University of Science and Technology Research Institute, Shenzhen 518000, People's Republic of China
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46
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Zhang ZQ, Wang CQ, Li LJ, Piper JL, Peng ZH, Ma JA, Zhang FG, Wu J. Programmable synthesis of difluorinated hydrocarbons from alkenes through a photocatalytic linchpin strategy. Chem Sci 2023; 14:11546-11553. [PMID: 37886092 PMCID: PMC10599468 DOI: 10.1039/d3sc03951j] [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: 07/31/2023] [Accepted: 09/21/2023] [Indexed: 10/28/2023] Open
Abstract
The introduction of difluoromethylene moieties into organic molecules has garnered significant attention due to their profound influence on the physicochemical and biological properties of compounds. Nonetheless, the existing approaches for accessing difluoroalkanes from readily available feedstock chemicals remain limited. In this study, we present an efficient and modular protocol for the synthesis of difluorinated compounds from alkenes, employing the readily accessible reagent, ClCF2SO2Na, as a versatile "difluoromethylene" linchpin. By means of an organophotoredox-catalysed hydrochlorodifluoromethylation of alkenes, followed by a ligated boryl radical-facilitated halogen atom transfer (XAT) process, we have successfully obtained various difluorinated compounds, including gem-difluoroalkanes, gem-difluoroalkenes, difluoromethyl alkanes, and difluoromethyl alkenes, with satisfactory yields. The practical utility of this linchpin strategy has been demonstrated through the successful preparation of CF2-linked derivatives of complex drugs and natural products. This method opens up new avenues for the synthesis of structurally diverse difluorinated hydrocarbons and highlights the utility of ligated boryl radicals in organofluorine chemistry.
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Affiliation(s)
- Zhi-Qi Zhang
- Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University Binhai New City Fuzhou 350207 P. R. China
- Department of Chemistry, Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University Tianjin 300072 P. R. China
- Department of Chemistry, National University of Singapore 3 Science Drive 3 Singapore 117543 Republic of Singapore
| | - Cheng-Qiang Wang
- Department of Chemistry, National University of Singapore 3 Science Drive 3 Singapore 117543 Republic of Singapore
| | - Long-Ji Li
- Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University Binhai New City Fuzhou 350207 P. R. China
- Department of Chemistry, National University of Singapore 3 Science Drive 3 Singapore 117543 Republic of Singapore
| | - Jared L Piper
- Pfizer Worldwide Research and Development Medicine Eastern Point Rd, Groton CT 06340 USA
| | - Zhi-Hui Peng
- Pfizer Worldwide Research and Development Medicine Eastern Point Rd, Groton CT 06340 USA
| | - Jun-An Ma
- Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University Binhai New City Fuzhou 350207 P. R. China
- Department of Chemistry, Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University Tianjin 300072 P. R. China
| | - Fa-Guang Zhang
- Department of Chemistry, Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University Tianjin 300072 P. R. China
| | - Jie Wu
- Department of Chemistry, National University of Singapore 3 Science Drive 3 Singapore 117543 Republic of Singapore
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47
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Tu YL, Zhang BB, Qiu BS, Wang ZX, Chen XY. Cross-Electrophile C-P III Coupling of Chlorophosphines with Organic Halides: Photoinduced P III and Aminoalkyl Radical Generation Enabled by Pnictogen Bonding. Angew Chem Int Ed Engl 2023; 62:e202310764. [PMID: 37668107 DOI: 10.1002/anie.202310764] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 09/04/2023] [Accepted: 09/05/2023] [Indexed: 09/06/2023]
Abstract
Pnictogen bonding (PnB) has gained recognition as an appealing strategy for constructing novel architectures and unlocking new properties. Within the synthetic community, the development of a straightforward and much simpler protocol for cross-electrophile C-PIII coupling remains an ongoing challenge with organic halides. In this study, we present a simple strategy for photoinduced PnB-enabled cross-electrophile C-PIII couplings using readily available chlorophosphines and organic halides via merging single electron transfer (SET) and halogen atom transfer (XAT) processes. In this photomediated transformation, the PnB formed between chlorophosphines and alkyl amines facilitates the photogeneration of PIII radicals and α-aminoalkyl radicals through SET. Subsequently, the resulting α-aminoalkyl radicals activate C-X bonds via XAT, leading to the formation of carbon radicals. This methodology offers operational simplicity and compatibility with both aliphatic and aromatic chlorophosphines and organic halides.
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Affiliation(s)
- Yong-Liang Tu
- School of Chemical Sciences, University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Bei-Bei Zhang
- School of Chemical Sciences, University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Bing-Sheng Qiu
- School of Chemical Sciences, University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhi-Xiang Wang
- School of Chemical Sciences, University of the Chinese Academy of Sciences, Beijing, 100049, China
- Binzhou Institute of Technology, Weiqiao-UCAS Science and Technology Park, Binzhou, Shandong Province, 256606, China
| | - Xiang-Yu Chen
- School of Chemical Sciences, University of the Chinese Academy of Sciences, Beijing, 100049, China
- Binzhou Institute of Technology, Weiqiao-UCAS Science and Technology Park, Binzhou, Shandong Province, 256606, China
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48
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Wang FD, Wang C, Wang M, Yan H, Jiang J, Li P. Visible-light-induced halocyclization of 2-alkynylthioanisoles with simple alkyl halides towards 3-halobenzo[ b]thiophenes without an external photocatalyst. Org Biomol Chem 2023; 21:8170-8175. [PMID: 37782212 DOI: 10.1039/d3ob00860f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/03/2023]
Abstract
A new strategy for the preparation of 3-halobenzo[b]thiophenes via a photo-driven halocyclization/demethylation of 2-alkynylthioanisoles with simple alkyl halides was developed. The reaction can proceed smoothly at room temperature under visible-light irradiation without any external photocatalyst, and the protocol has a range of advantages, including simplicity and mildness of the reaction conditions, good functional-group tolerance, and excellent yields of the products.
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Affiliation(s)
- Fen-Dou Wang
- College of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, P. R. China.
| | - Chunmiao Wang
- College of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, P. R. China.
| | - Min Wang
- College of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, P. R. China.
- Key Laboratory of Green and Precise Synthetic Chemistry and Applications, Ministry of Education; College of Chemistry and Materials Science, Huaibei Normal University, Huaibei, Anhui 235000, P.R. China.
| | - Han Yan
- College of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, P. R. China.
| | - Jin Jiang
- College of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, P. R. China.
| | - Pinhua Li
- College of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, P. R. China.
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49
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Zhong T, Gu C, Li Y, Huang J, Han J, Zhu C, Han J, Xie J. Manganese/Cobalt Bimetallic Relay Catalysis for Divergent Dehydrogenative Difluoroalkylation of Alkenes. Angew Chem Int Ed Engl 2023; 62:e202310762. [PMID: 37642584 DOI: 10.1002/anie.202310762] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 08/21/2023] [Accepted: 08/29/2023] [Indexed: 08/31/2023]
Abstract
The involvement of manganese radical for halogen atom transfer (XAT) reactions has been esteemed as one reliable method but encountered with limited catalytic models. In this paper, a novel bimetallic relay catalysis of Mn2 (CO)10 and cobaloxime has been developed for divergent dehydrogenative difluoroalkylation of alkenes using commercially available difluoroalkyl bromides. A wide range of structurally diverse terminal, cyclic and internal alkenes as well as tetrasubstituted alkenes are found to be good coupling partners to deliver difluoroalkylated allylic products and difluoromethylated cyclic products, accompanied with the production of H2 as the by-product. This bimetallic relay strategy features broad substrate scope, mild reaction conditions and excellent functional group compatibility. Its success represents an important step-forward to expedite the construction of a rich library of difluoroalkylated products.
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Affiliation(s)
- Tao Zhong
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Chengyihan Gu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Yuhang Li
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Jun Huang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Jian Han
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Chengjian Zhu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Jie Han
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Jin Xie
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
- State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources, College of Chemistry, Xinjiang University, Urumqi, 830017, China
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50
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Zhang Z, Zhu Q, Pyle D, Zhou X, Dong G. Methyl Ketones as Alkyl Halide Surrogates: A Deacylative Halogenation Approach for Strategic Functional Group Conversions. J Am Chem Soc 2023; 145:21096-21103. [PMID: 37712624 PMCID: PMC11102776 DOI: 10.1021/jacs.3c08176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/16/2023]
Abstract
Alkyl halides are versatile precursors to access diverse functional groups (FGs). Due to their lability, the development of surrogates for alkyl halides is strategically important for complex molecule synthesis. Given the stability and ease of derivatization inherent in common alkyl ketones, here we report a deacylative halogenation approach to convert various methyl ketones to the corresponding alkyl chlorides, bromides, and iodides. The reaction is driven by forming an aromatic byproduct, i.e., 1,2,4-triazole, in which N'-methylpicolinohydrazonamide (MPHA) is employed to form a prearomatic intermediate and halogen atom-transfer (XAT) reagents are used to quench the alkyl radical intermediate. The reaction is efficient in yielding primary and secondary alkyl halides from a wide range of methyl ketones with broad FG tolerance. It also works for complex natural-product-derived and fluoro-containing substrates. In addition, one-pot conversions of methyl ketones to various other FGs and annulations with alkenes and alkynes through deacylative halogenation are realized. Moreover, an unusual iterative homologation of alkyl iodides is also demonstrated. Finally, mechanistic studies reveal an intriguing double XAT process for the deacylative iodination reaction, which could have implications beyond this work.
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Affiliation(s)
- Zining Zhang
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Qi Zhu
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Daniel Pyle
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Xukai Zhou
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Guangbin Dong
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
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