1
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Tu JL, Huang B. Direct C(sp 3)-H functionalization with aryl and alkyl radicals as intermolecular hydrogen atom transfer (HAT) agents. Chem Commun (Camb) 2024; 60:11450-11465. [PMID: 39268687 DOI: 10.1039/d4cc03383c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/17/2024]
Abstract
Recent years have witnessed the emergence of direct intermolecular C(sp3)-H bond functionalization using in situ generated aryl/alkyl radicals as a unique class of hydrogen atom transfer (HAT) agents. A variety of precursors have been exploited to produce these radical HAT agents under photocatalytic, electrochemical or thermal conditions. To date, viable aryl radical precursors have included aryl diazonium salts or aryl azosulfones, diaryliodonium salts, O-benzoyl oximes, aryl sulfonium salts, aryl thioesters, and aryl halides; and applicable alkyl radical sources have included tetrahalogenated methanes (e.g., CCl3Br, CBr4 and CF3I), N-hydroxyphthalimide esters, alkyl bromides, and acetic acid. This review summarizes the current advances in direct intermolecular C(sp3)-H functionalization through key HAT events with in situ generated aryl/alkyl radicals and categorizes the procedures by the specific radical precursors applied. With an emphasis on the reaction conditions, mechanisms and representative substrate scopes of these protocols, this review aims to demonstrate the current trends and future challenges of this emerging field.
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Affiliation(s)
- Jia-Lin Tu
- Faculty of Arts and Sciences, Beijing Normal University, Zhuhai 519085, China.
- School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China
| | - Binbin Huang
- Faculty of Arts and Sciences, Beijing Normal University, Zhuhai 519085, China.
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2
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Qu HT, Zhou LS, Yang JX, Hong JH, Teng F, Xu K, Feng CT. I 2-Mediated [3 + 3] Annulation for the Construction of Indole-Pyrimidine-Pyrazole-Fused Tetracyclic Heteroarenes. J Org Chem 2024. [PMID: 39375821 DOI: 10.1021/acs.joc.4c01934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/09/2024]
Abstract
An I2-mediated annulation of 3-aminopyrazoles with indole-3-carboxaldehydes has been demonstrated for the first time. This tandem strategy allows the facile construction of indole-pyrimidine-pyrazole-fused tetracyclic heteroarenes that are otherwise inaccessible by the existing methods. These fused heterocycles exhibited enhanced antifungal activities against Valsa mali and Botryosphaeria dothidea compared with commercial Xemium fungicide.
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Affiliation(s)
- Heng-Tong Qu
- School of Pharmacy, Anhui University of Chinese Medicine; Anhui academy of Chinese medicine, Hefei 230012, China
| | - Long-Sheng Zhou
- School of Pharmacy, Anhui University of Chinese Medicine; Anhui academy of Chinese medicine, Hefei 230012, China
| | - Jia-Xin Yang
- School of Pharmacy, Anhui University of Chinese Medicine; Anhui academy of Chinese medicine, Hefei 230012, China
| | - Jia-Hui Hong
- School of Pharmacy, Anhui University of Chinese Medicine; Anhui academy of Chinese medicine, Hefei 230012, China
| | - Fan Teng
- School of Pharmacy, Anhui University of Chinese Medicine; Anhui academy of Chinese medicine, Hefei 230012, China
| | - Kun Xu
- College of Chemistry and Life Science, Beijing University of Technology, Beijing 100124, China
| | - Cheng-Tao Feng
- School of Pharmacy, Anhui University of Chinese Medicine; Anhui academy of Chinese medicine, Hefei 230012, China
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3
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Nan H, Cheng B, Zhang D, Wang K, Wang S, Xu B, Zhang S, König B, Zhang G. Direct Diazoarylation of [1.1.1]Propellane with Arenediazonium Salts: A Modular Assembly of Arylated Diazo Bicyclo[1.1.1]pentanes. Org Lett 2024; 26:8424-8429. [PMID: 39311486 DOI: 10.1021/acs.orglett.4c03316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/05/2024]
Abstract
A mild and concise diazoarylation of [1.1.1]propellane is described, which provides a modular approach to arylated diazo bicyclopentanes (BCPs). This reaction proceeds smoothly under basic conditions without requiring other additives or catalysts. The substrate scope shows that various electron-withdrawing and electron-donating groups are tolerated, and the subsequent modifications provide a novel avenue for assembling arylamino-BCP analogs.
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Affiliation(s)
- Hailing Nan
- School of Chemistry and Chemical Engineering, Yangzhou University, Siwangting Road 180, Yangzhou, Jiangsu 225002, China
| | - Beiyi Cheng
- Fakultät für Chemie und Pharmazie, Universität Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Duo Zhang
- Medicine Center, Guangxi University of Science and Technology, Liushi Road 257, Liuzhou, Guangxi 545006, China
| | - Kaiping Wang
- School of Chemistry and Chemical Engineering, Yangzhou University, Siwangting Road 180, Yangzhou, Jiangsu 225002, China
| | - Shuli Wang
- School of Chemistry and Chemical Engineering, Yangzhou University, Siwangting Road 180, Yangzhou, Jiangsu 225002, China
| | - Bingxin Xu
- Medicine Center, Guangxi University of Science and Technology, Liushi Road 257, Liuzhou, Guangxi 545006, China
| | - Shuwei Zhang
- School of Chemistry and Chemical Engineering, Yangzhou University, Siwangting Road 180, Yangzhou, Jiangsu 225002, China
| | - Burkhard König
- Fakultät für Chemie und Pharmazie, Universität Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Guodong Zhang
- School of Chemistry and Chemical Engineering, Yangzhou University, Siwangting Road 180, Yangzhou, Jiangsu 225002, China
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4
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Zhang TZ, Shen MQ, Zhang Q, Fu MC. Alcohols as Alkyl Electrophiles for Deoxygenative Heck Reaction Enabled by Excited State Pd Catalysis. Org Lett 2024. [PMID: 39356970 DOI: 10.1021/acs.orglett.4c03343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2024]
Abstract
Here, we present a general method for the photoinduced Pd-catalyzed deoxygenative Heck reaction of vinyl arenes with ortho-iodophenyl-thionocarbonate derived from alcohols. Mechanistic studies reveal that the deoxygenation involves a 5-endo-trig cyclization and fragmentation process, with radical addition identified as the rate-determining step in this transformation. This one-pot procedure demonstrates excellent selectivity for less hindered hydroxyl groups in diols, facilitating late-stage functionalization of complex molecules and scalability to gram-scale synthesis. The protocol highlights significant synthetic potential and can be extended to the cascade 1,1-difunctionalization of isocyanides and the intermolecular radical cascade cyclization of N-arylacrylamides.
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Affiliation(s)
- Tian-Zhen Zhang
- School of Chemistry and Chemical Engineering, Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, Department Flexible Composite Materials Key Technology Center, Hefei University of Technology, Hefei 230009, China
| | - Meng-Qi Shen
- School of Chemistry and Chemical Engineering, Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, Department Flexible Composite Materials Key Technology Center, Hefei University of Technology, Hefei 230009, China
| | - Qi Zhang
- School of Chemistry and Chemical Engineering, Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, Department Flexible Composite Materials Key Technology Center, Hefei University of Technology, Hefei 230009, China
| | - Ming-Chen Fu
- School of Chemistry and Chemical Engineering, Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, Department Flexible Composite Materials Key Technology Center, Hefei University of Technology, Hefei 230009, China
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5
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Zeng X. The Strategies Towards Electrochemical Generation of Aryl Radicals. Chemistry 2024; 30:e202402220. [PMID: 39012680 DOI: 10.1002/chem.202402220] [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: 06/09/2024] [Revised: 07/13/2024] [Accepted: 07/15/2024] [Indexed: 07/17/2024]
Abstract
The advancement in electrochemical techniques has unlocked a new path for achieving unprecedented oxidations and reductions of aryl radical precursors in a controlled and selective manner. This approach facilitates the construction of aromatic carbon-carbon and carbon-heteroatom bonds. In light of the green merits and the growing importance of this technique in aryl radical chemistry, this review aims to provide an overview of the recent advance in the electrochemical generation of aryl radicals organized by the aryl radical precursor type, with a focus on the substrate scope, limitation, and underlying mechanism, thereby inspiring future work on electrochemical aryl radical generation.
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Affiliation(s)
- Xiaobao Zeng
- School of Pharmacy and Nantong Key Laboratory of Small Molecular Drug Innovation, Nantong University, Nantong, 226019, People's Republic of China
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6
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Zeng L, Ouyang XH, He DL, Li JH. Synthesis of Diarylalkanes by Photoreductive 1,2-Diarylation of Alkenes with Aryl Halides and Cyanoaromatics. J Org Chem 2024; 89:13641-13653. [PMID: 39235129 DOI: 10.1021/acs.joc.4c01830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/06/2024]
Abstract
We report a visible light-induced photoreductive strategy for three-component diarylation of alkenes with aryl halides and cyanoaromatics. Upon photoredox catalysis and with tertiary alkyl amines as the electron transfer agent, aryl halides selectively undergo halogen atom transfer to generate the aryl radicals and two C(sp2)-C(sp3) bonds between the cabron atoms are created in a radical addition and radical-radical coupling fashion to rapidly assemble diverse functionalized polyarylalkanes with high regio- and chemoselectivity. This method can be applied to broad feedstocks, including terminal alkenes, internal alkenes, aryl iodides, aryl bromides, aryl chlorides, electron-deficient benzonitriles, and isonicotinonitriles.
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Affiliation(s)
- Liang Zeng
- 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
| | - Xuan-Hui Ouyang
- State Key Laboratory Base of Eco-Chemical Engineering, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, 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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7
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Wang XX, Jiao L. Dual Ligand Enabled Pd-Catalyzed Ortho-Alkylation of Iodoarenes. J Am Chem Soc 2024; 146:25552-25561. [PMID: 39236317 DOI: 10.1021/jacs.4c06544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/07/2024]
Abstract
The synthesis of complex polysubstituted aromatic molecules from simple precursors is a central goal in organic chemistry. In this study, we developed an approach for the ortho-alkylation of iodoarenes utilizing a dual ligand catalytic system. By combining Pd/olefin ligand cooperative catalysis with bulky trialkylphosphine ligand-promoted C(sp2)-I reductive elimination, we have established an ortho-alkylative Catellani-type reaction with the aryl-iodine bond reconstruction as the final step, which opens new synthetic opportunities within the Catellani-type reactions. Through in-depth mechanistic investigations, we have isolated and characterized key organopalladium intermediates, revealing the synergistic interaction of the dual ligands in merging the Catellani-type process with C(sp2)-I reductive elimination. The present study showcases the unique advantages of Pd/olefin ligand catalysis and emphasizes the effectiveness of the dual ligand system in expanding the chemical space of the Catellani chemistry.
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Affiliation(s)
- Xiao-Xia Wang
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Lei Jiao
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China
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8
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Chen Y, Chen Q, Zhang S, Feng K, Xu YQ, Chen X, Cao ZY, Kong X. Electrochemically Driven Denitrative Cyanation of Nitroarenes. Org Lett 2024; 26:7555-7559. [PMID: 39226075 DOI: 10.1021/acs.orglett.4c02552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
A practical denitrative cyanation of feedstock nitroarenes under mild and transition metal-free reaction conditions has been developed. The key to success lies in the use of electrochemically driven, inexpensive ionic liquid N-methylimidazolium p-toluenesulfonate-promoted selective cathode reduction of nitroarenes to anilines, followed by diazoation, cathode reduction to form the aryl radical, and the essential radical cyanation process in one pot. Our protocol shows broad functional group tolerance and can be applied for the modification of bioactive targets.
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Affiliation(s)
- Yiyi Chen
- School of Chemical Engineering and Materials, Changzhou Institute of Technology, No. 666 Liaohe Road, Changzhou 213032, China
| | - Qisheng Chen
- School of Chemical Engineering and Materials, Changzhou Institute of Technology, No. 666 Liaohe Road, Changzhou 213032, China
| | - Shuangquan Zhang
- School of Chemical Engineering and Materials, Changzhou Institute of Technology, No. 666 Liaohe Road, Changzhou 213032, China
| | - Kun Feng
- School of Chemical Engineering and Materials, Changzhou Institute of Technology, No. 666 Liaohe Road, Changzhou 213032, China
| | - Yuan-Qing Xu
- College of Chemistry and Chemical Engineering, Henan University, Kaifeng 475004, China
| | - Xiaohui Chen
- School of Chemical Engineering and Materials, Changzhou Institute of Technology, No. 666 Liaohe Road, Changzhou 213032, China
| | - Zhong-Yan Cao
- College of Chemistry and Chemical Engineering, Henan University, Kaifeng 475004, China
| | - Xianqiang Kong
- School of Chemical Engineering and Materials, Changzhou Institute of Technology, No. 666 Liaohe Road, Changzhou 213032, China
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9
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Das S, Kundu S, Metya A, Maji MS. A toolbox approach to revealing a series of naphthocarbazoles to showcase photocatalytic reductive syntheses. Chem Sci 2024; 15:13466-13474. [PMID: 39183925 PMCID: PMC11339970 DOI: 10.1039/d4sc03438d] [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: 05/26/2024] [Accepted: 07/14/2024] [Indexed: 08/27/2024] Open
Abstract
The development of highly reducing photocatalysts to functionalize arenes via the generation of reactive aryl radicals under mild and environmentally benign reaction conditions has emerged as a noteworthy approach in the realm of organic synthesis. Herein, we report a readily synthesized series of novel naphthocarbazole derivatives (NCs) as organo-photocatalysts, which, upon irradiation under 390 nm light, acquire high reducing power to catalyze several reductive transformations. The promising properties revealed by in depth photophysical and electrochemical studies ( = -1.9 V to -2.07 V vs. SCE, τ = 5.59 to 7.12 ns) demonstrate NCs to be versatile catalysts, and notably, rational variation of the substituents (NC1-NC6) modulates their success as efficient photoreductants. Detailed DFT calculations of the frontier MO diagrams and energy levels revealed them to be non-donor-acceptor type molecular scaffolds. The applicability of the NCs as catalysts was demonstrated in reductive dehalogenative borylation, phosphorylation, and dehydrohalide intramolecular C-C coupling reactions, as well as the dimerization of carbonyls and imines. Visible-light-irradiated selective reductive desulfonylation from heteroaromatics and peptides further enhances their synthetic utility.
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Affiliation(s)
- Sharmila Das
- Department of Chemistry, Indian Institute of Technology Kharagpur Kharagpur 721302 WB India
| | - Samrat Kundu
- Department of Chemistry, Indian Institute of Technology Kharagpur Kharagpur 721302 WB India
| | - Abhisek Metya
- Department of Chemistry, Indian Institute of Technology Kharagpur Kharagpur 721302 WB India
| | - Modhu Sudan Maji
- Department of Chemistry, Indian Institute of Technology Kharagpur Kharagpur 721302 WB India
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10
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Janaagal A, Kushwaha A, Jhaldiyal P, Dhilip Kumar TJ, Gupta I. Photoredox Catalysis by 21-Thiaporphyrins: A Green and Efficient Approach for C-N Borylation and C-H Arylation. Chemistry 2024; 30:e202401623. [PMID: 38825798 DOI: 10.1002/chem.202401623] [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: 04/24/2024] [Revised: 05/27/2024] [Accepted: 05/31/2024] [Indexed: 06/04/2024]
Abstract
Photoredox catalysis provides a green and sustainable alternative for C-H activation of organic molecules that eludes harsh conditions and use of transition metals. The photocatalytic C-N borylation and C-H arylation mostly depend on the ruthenium and iridium complexes or eosin Y and the use of porphyrin catalysts is still in infancy. A series of novel 21-thiaporphyrins (A2B2 and A3B type) were synthesized having carbazole/phenothiazine moieties at their meso-positions and screened as catalysts for C-N borylation and C-H arylation. This paper demonstrates the 21-thiaporphyrin catalyzed C-N borylation and het-arylation of anilines under visible light. The method utilizes only 0.1 mol % of 21-thiaporphyrin catalyst under blue light for the direct C-N borylation and het-arylation reactions. A variety of substituted anilines were used as source for expensive and unstable aryl diazonium salts in the reactions. The heterobiaryls and aryl boronic esters were obtained in decent yields (up to 88 %). Versatility of the 21-thiaporphyrin catalyst was tested by thiolation and selenylation of anilines under similar conditions. Mechanistic insight was obtained from DFT studies, suggesting that 21-thiaporphyrin undergo an oxidative quenching pathway. The photoredox process catalyzed by 21-thiaporphyrins offers a mild, efficient and metal-free alternative for the formation of C-C, C-S, and C-Se bonds in aryl compounds; it can also be extended to borylation reaction.
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Affiliation(s)
- Anu Janaagal
- Indian Institute of Technology Gandhinagar, Palaj, Gandhinagar, Gujarat, 382055, India
| | - Apoorv Kushwaha
- Department of Chemistry, Indian Institute of Technology, Ropar, Rupnagar, 140001, India
| | - Pranjali Jhaldiyal
- Indian Institute of Technology Gandhinagar, Palaj, Gandhinagar, Gujarat, 382055, India
| | - T J Dhilip Kumar
- Department of Chemistry, Indian Institute of Technology, Ropar, Rupnagar, 140001, India
| | - Iti Gupta
- Indian Institute of Technology Gandhinagar, Palaj, Gandhinagar, Gujarat, 382055, India
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11
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Spiller TE, Donabauer K, Brooks AF, Witek JA, Bowden GD, Scott PJH, Sanford MS. Room-Temperature Photochemical Copper-Mediated Fluorination of Aryl Iodides. Org Lett 2024; 26:6433-6437. [PMID: 39024514 PMCID: PMC11316249 DOI: 10.1021/acs.orglett.4c02227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
This report describes a method for the photochemical Cu-mediated fluorination of aryl iodides with AgF via putative aryl radical (Ar•) intermediates. It involves irradiating an aryl iodide with UVB light (λmax = 313 nm) in the presence of a mixture of CuI and CuII salts and AgF. Under these conditions, fluorination proceeds at room temperature for substrates containing diverse substituents, including alkoxy and alkyl groups, ketones, esters, sulfonate esters, sulfonamides, and protected amines. This method has been translated to radiofluorination using a combination of K18F, K3PO4, and AgOTf.
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Affiliation(s)
- Taylor E. Spiller
- Department of Chemistry, University of Michigan, 930 North Avenue, Ann Arbor, Michigan, 48104, United States
| | - Karsten Donabauer
- Department of Chemistry, University of Michigan, 930 North Avenue, Ann Arbor, Michigan, 48104, United States
| | - Allen F. Brooks
- Department of Radiology, University of Michigan Medical School, 1301 Catherine Street, Ann Arbor, Michigan 48109, United States
| | - Jason A. Witek
- Department of Radiology, University of Michigan Medical School, 1301 Catherine Street, Ann Arbor, Michigan 48109, United States
| | - Gregory D. Bowden
- Department of Radiology, University of Michigan Medical School, 1301 Catherine Street, Ann Arbor, Michigan 48109, United States
| | - Peter J. H. Scott
- Department of Radiology, University of Michigan Medical School, 1301 Catherine Street, Ann Arbor, Michigan 48109, United States
| | - Melanie S. Sanford
- Department of Chemistry, University of Michigan, 930 North Avenue, Ann Arbor, Michigan, 48104, United States
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12
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Zhou Y, Yang WH, Dai NN, Feng JY, Yang MQ, Gao W, Li Q, Deng C, Lu Z, Wei WT. Dual Nickel/Photoredox-Catalyzed Arylsulfonylation of Allenes. Org Lett 2024; 26:5074-5081. [PMID: 38857312 DOI: 10.1021/acs.orglett.4c01258] [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 nickel/photoredox dual catalysis system is an efficient conversion platform for the difunctionalization of unsaturated hydrocarbons. Herein, we disclose the first dual nickel/photoredox-catalyzed intramolecular 1,2-arylsulfonylation of allenes, which can accurately construct a C(sp2)-C(sp2) bond and a C(sp3)-S bond. The reaction exhibits excellent chemoselectivity and regioselectivity, allowing modular conformations of a diverse series of 3-sulfonylmethylbenzofuran derivatives. Control experiments showed that the bipyridine ligand is crucial for the formation of a stable σ-alkyl nickel intermediate, providing the possibility for sulfonyl radical insertion. Meanwhile, the electrophilic sulfonyl radical facilitates further oxidative addition of the σ-alkyl nickel intermediate and inhibits addition with allenes. In addition, control experiments, cyclic voltammetry tests, Stern-Volmer experiments, and density functional theory calculations afford evidence for the Ni(0)/Ni(I)/Ni(II)/Ni(III) pathway in this 1,2-arylsulfonylation.
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Affiliation(s)
- Yu Zhou
- School of Materials Science and Chemical Engineering, Ningbo University, Zhejiang 315211, China
| | - Wen-Hui Yang
- School of Materials Science and Chemical Engineering, Ningbo University, Zhejiang 315211, China
| | - Nan-Nan Dai
- School of Materials Science and Chemical Engineering, Ningbo University, Zhejiang 315211, China
| | - Jia-Yao Feng
- School of Materials Science and Chemical Engineering, Ningbo University, Zhejiang 315211, China
| | - Ming-Qi Yang
- School of Materials Science and Chemical Engineering, Ningbo University, Zhejiang 315211, China
| | - Wenqing Gao
- School of Materials Science and Chemical Engineering, Ningbo University, Zhejiang 315211, China
| | - Qiang Li
- Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng, Shandong 252000, China
| | - Chao Deng
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Zhan Lu
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Wen-Ting Wei
- School of Materials Science and Chemical Engineering, Ningbo University, Zhejiang 315211, China
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13
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Wang JZ, Mao E, Nguyen JA, Lyon WL, MacMillan DWC. Triple Radical Sorting: Aryl-Alkylation of Alkenes. J Am Chem Soc 2024; 146:15693-15700. [PMID: 38820134 DOI: 10.1021/jacs.4c05744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2024]
Abstract
The cross-coupling of aryl bromides with alkenes can provide access to diverse combinatorial chemical space. Two-component couplings between these partners are well-known, but three-component aryl-functionalizations of unactivated alkenes remain underdeveloped. In particular, the aryl-alkylation of unactivated alkenes would allow for rapid construction of molecular complexity and the expedient exploration of a pharmaceutically relevant and C(sp3)-rich structural landscape. Herein, we report a general approach toward the aryl-alkylation of alkenes through a triple radical sorting mechanism. Over the course of the reaction, a high energy aryl radical, a primary radical, and a hindered alkyl radical are simultaneously formed. Through mediation by a nickel-based catalyst, the three radicals are sorted into productive bond-forming pathways toward the efficient aryl-alkylation of alkenes. A wide range of electronically and sterically differentiated alkenes and aryl radical precursors can be used to access complex scaffolds. This method was further applied to the synthesis of highly substituted semisaturated fused heterocycles.
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Affiliation(s)
- Johnny Z Wang
- Merck Center for Catalysis at Princeton University, Princeton, New Jersey 08544, United States
| | - Edna Mao
- Merck Center for Catalysis at Princeton University, Princeton, New Jersey 08544, United States
| | - Jennifer A Nguyen
- Merck Center for Catalysis at Princeton University, Princeton, New Jersey 08544, United States
| | - William L Lyon
- Merck Center for Catalysis at Princeton University, Princeton, New Jersey 08544, United States
| | - David W C MacMillan
- Merck Center for Catalysis at Princeton University, Princeton, New Jersey 08544, United States
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14
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Bryden MA, Crovini E, Comerford T, Studer A, Zysman-Colman E. Organic Donor-Acceptor Thermally Activated Delayed Fluorescence Photocatalysts in the Photoinduced Dehalogenation of Aryl Halides. Angew Chem Int Ed Engl 2024; 63:e202405081. [PMID: 38600037 DOI: 10.1002/anie.202405081] [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: 03/14/2024] [Revised: 04/02/2024] [Accepted: 04/10/2024] [Indexed: 04/12/2024]
Abstract
We report a family of donor-acceptor thermally activated delayed fluorescent (TADF) compounds based on derivatives of DMAC-TRZ, that are strongly photoreducing. Both Eox and thus E*ox could be tuned via substitution of the DMAC donor with a Hammett series of p-substituted phenyl moieties while Ered remained effectively constant. These compounds were assessed in the photoinduced dehalogenation of aryl halides, and analogues bearing electron withdrawing groups were found to produce the highest yields. Substrates of up to Ered=-2.72 V could be dehalogenated at low PC loading (1 mol %) and under air, conditions much milder than previously reported for this reaction. Spectroscopic and chemical studies demonstrate that all PCs, including literature reference PCs, photodegrade, and that it is these photodegradation products that are responsible for the reactivity.
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Affiliation(s)
- Megan Amy Bryden
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, United Kingdom
| | - Ettore Crovini
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, United Kingdom
| | - Thomas Comerford
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, United Kingdom
| | - Armido Studer
- Organisch-Chemisches Institut, University of Münster, Corrensstaße 40, 48149, Münster, Germany
| | - Eli Zysman-Colman
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, United Kingdom
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15
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Yamamoto K, Arita K, Kuriyama M, Onomura O. Transition-metal-catalyst-free electroreductive alkene hydroarylation with aryl halides under visible-light irradiation. Beilstein J Org Chem 2024; 20:1327-1333. [PMID: 38887578 PMCID: PMC11181238 DOI: 10.3762/bjoc.20.116] [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: 03/21/2024] [Accepted: 05/22/2024] [Indexed: 06/20/2024] Open
Abstract
The radical hydroarylation of alkenes is an efficient strategy for accessing linear alkylarenes with high regioselectivity. Herein, we report the electroreductive hydroarylation of electron-deficient alkenes and styrene derivatives using (hetero)aryl halides under mild reaction conditions. Notably, the present hydroarylation proceeded with high efficiency under transition-metal-catalyst-free conditions. The key to success is the use of 1,3-dicyanobenzene as a redox mediator and visible-light irradiation, which effectively suppresses the formation of simple reduction, i.e., hydrodehalogenation, products to afford the desired products in good to high yields. Mechanistic investigations proposed that a reductive radical-polar crossover pathway is likely to be involved in this transformation.
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Affiliation(s)
- Kosuke Yamamoto
- Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Kazuhisa Arita
- Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Masami Kuriyama
- Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Osamu Onomura
- Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
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16
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Supranovich VI, Levin VV, Dilman AD. One-Step Transformation of Aryl Diazonium Salts into Aryl Indium(III) Reagents. Org Lett 2024; 26:4537-4541. [PMID: 38771980 DOI: 10.1021/acs.orglett.4c01448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2024]
Abstract
A method for the conversion of diazonium salts into intrinsically nucleophilic aryl indium reagents is described. The reaction is performed using indium(I) bromide with the C-In bond being formed by the interaction of aryl radicals with the indium salt. The obtained aryl indium(III) reagents work well in the Liebeskind-Srogl cross-coupling with thioesters, affording a wide variety of aryl ketones. This two-step transformation is a general method for the acylation of diazonium salts.
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Affiliation(s)
- Vyacheslav I Supranovich
- N. D. Zelinsky Institute of Organic Chemistry, Leninsky Prospekt 47, 119991 Moscow, Russian Federation
| | - Vitalij V Levin
- N. D. Zelinsky Institute of Organic Chemistry, Leninsky Prospekt 47, 119991 Moscow, Russian Federation
| | - Alexander D Dilman
- N. D. Zelinsky Institute of Organic Chemistry, Leninsky Prospekt 47, 119991 Moscow, Russian Federation
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17
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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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18
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Zubkov MO, Dilman AD. Radical reactions enabled by polyfluoroaryl fragments: photocatalysis and beyond. Chem Soc Rev 2024; 53:4741-4785. [PMID: 38536104 DOI: 10.1039/d3cs00889d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Polyfluoroarenes have been known for a long time, but they are most often used as fluorinated building blocks for the synthesis of aromatic compounds. At the same time, due to peculiar fluorine effect, they have unique properties that provide applications in various fields ranging from synthesis to materials science. This review summarizes advances in the radical chemistry of polyfluoroarenes, which have become possible mainly with the advent of photocatalysis. Transformations of the fluorinated ring via the C-F bond activation, as well as use of fluoroaryl fragments as activating groups and hydrogen atom transfer agents are discussed. The ability of fluoroarenes to serve as catalysts is also considred.
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Affiliation(s)
- Mikhail O Zubkov
- N. D. Zelinsky Institute of Organic Chemistry, Leninsky prosp. 47, 119991 Moscow, Russian Federation.
| | - Alexander D Dilman
- N. D. Zelinsky Institute of Organic Chemistry, Leninsky prosp. 47, 119991 Moscow, Russian Federation.
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19
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Maillot B, Audibert JF, Miomandre F, Brasiliense V. Nanometrology based control: taming radical grafting reactions with attoliter precision. NANOSCALE 2024; 16:7594-7602. [PMID: 38506368 DOI: 10.1039/d3nr06324k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
Precisely controlled micropatterning with organic moieties is a promising route for designing smart surfaces, enabling the development of microsensors and actuators with optimal usage of reactants. Such applications require fine control over the surface modification process, which in turn demands detailed knowledge about the surface modification process. As complex surface kinetics often emerge as a result of even slight modifications of the grafting entity, non-invasive, sensitive and precise closed loop control strategies are highly desirable. In this paper we demonstrate that a nanometrology approach based on quantitative phase imaging (QPI) fulfill all these requirements. We first use the technique to monitor surface photografting kinetics of aryl radicals, comprehensively analyzing the effect of substituents on surface addition reactions. We demonstrate that several aspects of the grafting process are affected in complex ways, rendering open-loop strategies impossible to implement precisely. Then, we show that the operando optical phase signal can be used as a direct feedback, guiding the grafting reaction process. Using relatively simple instrumentation, we demonstrate that general and precise control strategies can be designed and used to control the volume of the grafting material with attoliter precision, in spite of radically different surface modification kinetics spanning several orders of magnitude.
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Affiliation(s)
- Baptiste Maillot
- Université Paris-Saclay, ENS Paris-Saclay, CNRS, PPSM, 4 avenue des sciences, 91190 Gif-sur-Yvette, France.
| | - Jean-Frédéric Audibert
- Université Paris-Saclay, ENS Paris-Saclay, CNRS, PPSM, 4 avenue des sciences, 91190 Gif-sur-Yvette, France.
| | - Fabien Miomandre
- Université Paris-Saclay, ENS Paris-Saclay, CNRS, PPSM, 4 avenue des sciences, 91190 Gif-sur-Yvette, France.
| | - Vitor Brasiliense
- Université Paris-Saclay, ENS Paris-Saclay, CNRS, PPSM, 4 avenue des sciences, 91190 Gif-sur-Yvette, France.
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20
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Li M, Deng YH, Chang Q, Li J, Wang C, Wang L, Sun TY. Photoinduced Site-Selective Aryl C-H Borylation with Electron-Donor-Acceptor Complex Derived from B 2Pin 2 and Isoquinoline. Molecules 2024; 29:1783. [PMID: 38675603 PMCID: PMC11052414 DOI: 10.3390/molecules29081783] [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: 03/26/2024] [Revised: 04/08/2024] [Accepted: 04/08/2024] [Indexed: 04/28/2024] Open
Abstract
Due to boron's metalloid properties, aromatic boron reagents are prevalent synthetic intermediates. The direct borylation of aryl C-H bonds for producing aromatic boron compounds offers an appealing, one-step solution. Despite significant advances in this field, achieving regioselective aryl C-H bond borylation using simple and readily available starting materials still remains a challenge. In this work, we attempted to enhance the reactivity of the electron-donor-acceptor (EDA) complex by selecting different bases to replace the organic base (NEt3) used in our previous research. To our delight, when using NH4HCO3 as the base, we have achieved a mild visible-light-mediated aromatic C-H bond borylation reaction with exceptional regioselectivity (rr > 40:1 to single isomers). Compared with our previous borylation methodologies, this protocol provides a more efficient and broader scope for aryl C-H bond borylation through the use of N-Bromosuccinimide. The protocol's good functional-group tolerance and excellent regioselectivity enable the functionalization of a variety of biologically relevant compounds and novel cascade transformations. Mechanistic experiments and theoretical calculations conducted in this study have indicated that, for certain arenes, the aryl C-H bond borylation might proceed through a new reaction mechanism, which involves the formation of a novel transient EDA complex.
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Affiliation(s)
- Manhong Li
- Key Lab of Computational Chemistry and Drug Design, State Key Laboratory of Chemical Oncogenomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China; (M.L.); (Y.-H.D.); (C.W.)
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, No. 66, Gongchang Road, Shenzhen 518107, China;
- Institute of Molecular Chemical Biology, Shenzhen Bay Laboratory, Shenzhen 518132, China
- Department of Pharmacy and Pharmaceutical Sciences, Faculty of Science, National University of Singapore, Block S4A, Level 3, 18 Science Drive 4, Singapore 117543, Singapore
| | - Yi-Hui Deng
- Key Lab of Computational Chemistry and Drug Design, State Key Laboratory of Chemical Oncogenomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China; (M.L.); (Y.-H.D.); (C.W.)
| | - Qianqian Chang
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, No. 66, Gongchang Road, Shenzhen 518107, China;
| | - Jinyuan Li
- Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China;
| | - Chao Wang
- Key Lab of Computational Chemistry and Drug Design, State Key Laboratory of Chemical Oncogenomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China; (M.L.); (Y.-H.D.); (C.W.)
| | - Leifeng Wang
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, No. 66, Gongchang Road, Shenzhen 518107, China;
| | - Tian-Yu Sun
- Key Lab of Computational Chemistry and Drug Design, State Key Laboratory of Chemical Oncogenomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China; (M.L.); (Y.-H.D.); (C.W.)
- Institute of Molecular Chemical Biology, Shenzhen Bay Laboratory, Shenzhen 518132, China
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21
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Cai Y, Gaurav G, Ritter T. 1,4-Aminoarylation of Butadienes via Photoinduced Palladium Catalysis. Angew Chem Int Ed Engl 2024; 63:e202311250. [PMID: 38334292 DOI: 10.1002/anie.202311250] [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: 08/03/2023] [Revised: 02/01/2024] [Accepted: 02/02/2024] [Indexed: 02/10/2024]
Abstract
A visible-light-induced, three-component palladium-catalyzed 1,4-aminoarylation of butadienes with readily available aryl halides and aliphatic amines has been developed, affording allylamines with excellent E-selectivity. The reaction exhibits exceptional control over chemo-, regio-, and stereoselectivity, a broad substrate scope, and high functional group compatibility, as demonstrated by the late-stage functionalization of bioactive molecules. Mechanistic investigations are consistent with a photoinduced radical Pd(0)-Pd(I)-Pd(II)-Pd(0) Heck-Tsuji-Trost allylation cascade.
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Affiliation(s)
- Yuan Cai
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470, Mülheim an der Ruhr, Germany
| | - Gaurav Gaurav
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470, Mülheim an der Ruhr, Germany
| | - Tobias Ritter
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470, Mülheim an der Ruhr, Germany
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22
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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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23
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Azpilcueta-Nicolas CR, Lumb JP. Mechanisms for radical reactions initiating from N-hydroxyphthalimide esters. Beilstein J Org Chem 2024; 20:346-378. [PMID: 38410775 PMCID: PMC10896223 DOI: 10.3762/bjoc.20.35] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 01/29/2024] [Indexed: 02/28/2024] Open
Abstract
Due to their ease of preparation, stability, and diverse reactivity, N-hydroxyphthalimide (NHPI) esters have found many applications as radical precursors. Mechanistically, NHPI esters undergo a reductive decarboxylative fragmentation to provide a substrate radical capable of engaging in diverse transformations. Their reduction via single-electron transfer (SET) can occur under thermal, photochemical, or electrochemical conditions and can be influenced by a number of factors, including the nature of the electron donor, the use of Brønsted and Lewis acids, and the possibility of forming charge-transfer complexes. Such versatility creates many opportunities to influence the reaction conditions, providing a number of parameters with which to control reactivity. In this perspective, we provide an overview of the different mechanisms for radical reactions involving NHPI esters, with an emphasis on recent applications in radical additions, cyclizations and decarboxylative cross-coupling reactions. Within these reaction classes, we discuss the utility of the NHPI esters, with an eye towards their continued development in complexity-generating transformations.
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Affiliation(s)
| | - Jean-Philip Lumb
- Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, Quebec H3A 0B8, Canada
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24
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Mao X, Li MM, Wang P, Cao Q, Zhou W, Ding W. Transition-Metal-Free Anti-Markovnikov Hydroarylation of Alkenes with Aryl Chlorides through Consecutive Photoinduced Electron Transfer. Org Lett 2024; 26:1265-1270. [PMID: 38319734 DOI: 10.1021/acs.orglett.4c00106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2024]
Abstract
The hydroarylation of alkenes has emerged as a powerful strategy for arene functionalization. However, aryl chlorides remain a large challenge in this type of reaction due to the chemical inertness of the C(sp2)-Cl bond and high negative reduction potential. Herein, we report an anti-Markovnikov radical hydroarylation of alkenes with aryl chlorides via visible-light photoredox catalysis. The key reactive aryl radicals can be efficiently achieved from aryl chlorides by consecutive photoinduced electron transfer. This transition-metal-free protocol features mild conditions, a wide substrate scope, and functional group tolerance, producing a diverse range of linear alkylarenes in moderate to good yields. The reaction is proposed to proceed through a radical-polar crossover pathway.
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Affiliation(s)
- Xudong Mao
- Division of Molecular Catalysis and Synthesis, Henan Institute of Advanced Technology, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Miao-Miao Li
- Division of Molecular Catalysis and Synthesis, Henan Institute of Advanced Technology, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Pengfei Wang
- Technology Center of China Tobacco Henan Industrial Co., Ltd, Zhengzhou 450000, P. R. China
| | - Qingzhi Cao
- Division of Molecular Catalysis and Synthesis, Henan Institute of Advanced Technology, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Wei Zhou
- Department of Orthopedics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, P. R. China
| | - Wei Ding
- Division of Molecular Catalysis and Synthesis, Henan Institute of Advanced Technology, Zhengzhou University, Zhengzhou 450001, P. R. China
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25
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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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26
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Gentile G, Bartolomei B, Dosso J, Demitri N, Filippini G, Prato M. Synthesis of a novel tetra-phenol π-extended phenazine and its application as an organo-photocatalyst. Chem Commun (Camb) 2024; 60:602-605. [PMID: 38099872 DOI: 10.1039/d3cc05176e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Abstract
In this paper, the synthesis of a novel tetra-phenol π-extended dihydrophenazine is reported. The obtained derivative presents marked reducing properties in the excited state and was exploited as an organo-photocatalyst in dehalogenation and C-C bond formation reactions. These results underline the great potential of functionalized π-extended dihydrophenazines as organo-photocatalysts.
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Affiliation(s)
- Giuseppe Gentile
- Department of Chemical and Pharmaceutical Sciences, CENMAT, Centre of Excellence for Nanostructured Materials, INSTM UdR Trieste, University of Trieste, via Licio Giorgieri 1, 34127 Trieste, Italy.
| | - Beatrice Bartolomei
- Department of Chemical and Pharmaceutical Sciences, CENMAT, Centre of Excellence for Nanostructured Materials, INSTM UdR Trieste, University of Trieste, via Licio Giorgieri 1, 34127 Trieste, Italy.
| | - Jacopo Dosso
- Department of Chemical and Pharmaceutical Sciences, CENMAT, Centre of Excellence for Nanostructured Materials, INSTM UdR Trieste, University of Trieste, via Licio Giorgieri 1, 34127 Trieste, Italy.
| | - Nicola Demitri
- Elettra-Sincrotrone, Trieste S.S. 14 Km 163.5, Area Science Park, 34149 Basovizza, Trieste, Italy
| | - Giacomo Filippini
- Department of Chemical and Pharmaceutical Sciences, CENMAT, Centre of Excellence for Nanostructured Materials, INSTM UdR Trieste, University of Trieste, via Licio Giorgieri 1, 34127 Trieste, Italy.
| | - Maurizio Prato
- Department of Chemical and Pharmaceutical Sciences, CENMAT, Centre of Excellence for Nanostructured Materials, INSTM UdR Trieste, University of Trieste, via Licio Giorgieri 1, 34127 Trieste, Italy.
- Centre for Cooperative Research in Biomaterials (CIC BiomaGUNE), Basque Research and Technology Alliance (BRTA), Paseo de Miramón 194, 20014, Donostia San Sebastián, Spain
- Basque Fdn Sci, Ikerbasque, 48013 Bilbao, Spain
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27
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Dawson G, Spielvogel EH, Diao T. Nickel-Catalyzed Radical Mechanisms: Informing Cross-Coupling for Synthesizing Non-Canonical Biomolecules. Acc Chem Res 2023; 56:3640-3653. [PMID: 38033206 PMCID: PMC10734253 DOI: 10.1021/acs.accounts.3c00588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 10/30/2023] [Accepted: 11/03/2023] [Indexed: 12/02/2023]
Abstract
Nickel excels at facilitating selective radical chemistry, playing a pivotal role in metalloenzyme catalysis and modern cross-coupling reactions. Radicals, being nonpolar and neutral, exhibit orthogonal reactivity to nucleophilic and basic functional groups commonly present in biomolecules. Harnessing this compatibility, we delve into the application of nickel-catalyzed radical pathways in the synthesis of noncanonical peptides and carbohydrates, critical for chemical biology studies and drug discovery.We previously characterized a sequential reduction mechanism that accounts for chemoselectivity in cross-electrophile coupling reactions. This catalytic cycle begins with nickel(I)-mediated radical generation from alkyl halides, followed by carbon radical capture by nickel(II) complexes, and concludes with reductive elimination. These steps resonate with mechanistic proposals in nickel-catalyzed cross-coupling, photoredox, and electrocatalytic reactions. Herein, we present our insights into each step involving radicals, including initiation, propagation, termination, and the nuances of kinetics, origins of selectivity, and ligand effects.Radical generation from C(sp3) electrophiles via one-electron oxidative addition with low-valent nickel radical intermediates provides the basis for stereoconvergent and cross-electrophile couplings. Our electroanalytical studies elucidate a concerted halogen atom abstraction mechanism, where electron transfer is coupled with halide dissociation. Using this pathway, we have developed a nickel-catalyzed stereoselective radical addition to dehydroalanine, facilitating the synthesis of noncanonical peptides. In this application, chiral ligands modulate the stereochemical outcome through the asymmetric protonation of a nickel-enolate intermediate.The capture of the alkyl radical by nickel(II) expands the scope of cross-coupling, promotes reductive elimination through the formation of high-valent nickel(III) species, and governs chemo- and stereoselectivity. We discovered that nickel(II)-aryl efficiently traps radicals with a barrier ranging from 7 to 9 kcal/mol, followed by fast reductive elimination. In contrast, nickel(II)-alkyl captures radicals to form a nickel(III) species, which was characterized by EPR spectroscopy. However, the subsequent slow reductive elimination resulted in minimal product formation. The observed high diastereoselectivity of radical capture inspired investigations into C-aryl and C-acyl glycosylation reactions. We developed a redox auxiliary that readily couples with natural carbohydrates and produces glycosyl radicals upon photoredox activation. Nickel-catalyzed cross-coupling of the glycosyl radical with bromoarenes and carboxylic acids leads to diverse non-natural glycosides that can facilitate drug discovery.Stoichiometric studies on well-defined d8-nickel complexes have showcased means to promote reductive elimination, including ligand association, oxidation, and oxidative addition.In the final section, we address the influence of auxiliary ligands on the electronic structure and redox activity of organonickel intermediates. Synthesis of a series of low-valent nickel radical complexes and characterization of their electronic structures led us to a postulate that ligand redox activity correlates with coordination geometry. Our data reveal that a change in ligand redox activity can shift the redox potentials of reaction intermediates, potentially altering the mechanism of catalytic reactions. Moreover, coordinating additives and solvents may stabilize nickel radicals during catalysis by adjusting ligand redox activity, which is consistent with known catalytic conditions.
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Affiliation(s)
- Gregory
A. Dawson
- Department
of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, United States
| | - Ethan H. Spielvogel
- Department
of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, United States
| | - Tianning Diao
- Department
of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, United States
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28
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Heppe BJ, Dzombic N, Keil JM, Sun XL, Ao G. Solvent Isotope Effects on the Creation of Fluorescent Quantum Defects in Carbon Nanotubes by Aryl Diazonium Chemistry. J Am Chem Soc 2023; 145:25621-25631. [PMID: 37971308 DOI: 10.1021/jacs.3c07341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2023]
Abstract
The integration of aryl diazonium and carbon nanotube chemistries has offered rich and versatile tools for creating nanomaterials of unique optical and electronic properties in a controllable fashion. The diazonium reaction with single-wall carbon nanotubes (SWCNTs) is known to proceed through a radical or carbocation mechanism in aqueous solutions, with deuterated water (D2O) being the frequently used solvent. Here, we show strong water solvent isotope effects on the aryl diazonium reaction with SWCNTs for creating fluorescent quantum defects using water (H2O) and D2O. We found a deduced reaction constant of ∼18.2 times larger value in D2O than in H2O, potentially due to their different chemical properties. We also observed the generation of new defect photoluminescence over a broad concentration range of diazonium reactants in H2O, as opposed to a narrow window of reaction conditions in D2O under UV excitation. Without UV light, the physical adsorption of diazonium on the surface of SWCNTs led to the fluorescence quenching of nanotubes. These findings provide important insights into the aryl diazonium chemistry with carbon nanotubes for creating promising material platforms for optical sensing, imaging, and quantum communication technologies.
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Affiliation(s)
- Brandon J Heppe
- Department of Chemical and Biomedical Engineering, Washkewicz College of Engineering, Cleveland State University, 2121 Euclid Avenue, Cleveland, Ohio 44115, United States
| | - Nina Dzombic
- Department of Chemical and Biomedical Engineering, Washkewicz College of Engineering, Cleveland State University, 2121 Euclid Avenue, Cleveland, Ohio 44115, United States
| | - Joseph M Keil
- Department of Chemistry, Center for Gene Regulation in Health and Disease (GRHD), Cleveland State University, 2121 Euclid Avenue, Cleveland, Ohio 44115, United States
| | - Xue-Long Sun
- Department of Chemical and Biomedical Engineering, Washkewicz College of Engineering, Cleveland State University, 2121 Euclid Avenue, Cleveland, Ohio 44115, United States
- Department of Chemistry, Center for Gene Regulation in Health and Disease (GRHD), Cleveland State University, 2121 Euclid Avenue, Cleveland, Ohio 44115, United States
| | - Geyou Ao
- Department of Chemical and Biomedical Engineering, Washkewicz College of Engineering, Cleveland State University, 2121 Euclid Avenue, Cleveland, Ohio 44115, United States
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29
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Meher P, Panda SP, Mahapatra SK, Thombare KR, Roy L, Murarka S. A General Electron Donor-Acceptor Photoactivation Platform of Diaryliodonium Reagents: Arylation of Heterocycles. Org Lett 2023; 25:8290-8295. [PMID: 37962249 DOI: 10.1021/acs.orglett.3c03365] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
We report a photoredox system comprising sodium iodide, triphenyl phosphine, and N,N,N',N'-tetramethylethylenediamine (TMEDA) that can form a self-assembled tetrameric electron donor-acceptor (EDA) complex with diaryliodonium reagents (DAIRs) and furnish aryl radicals upon visible light irradiation. This practical mode of activation of DAIRs enables arylation of an array of heterocycles under mild conditions to provide the respective heteroaryl-(hetero)aryl assembly in moderate to excellent yields. Detailed mechanistic investigations comprising photophysical and DFT studies provided insight into the reaction mechanism.
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Affiliation(s)
- Prahallad Meher
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Rajasthan 342037, India
| | - Satya Prakash Panda
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Rajasthan 342037, India
| | - Sanat Kumar Mahapatra
- Institute of Chemical Technology Mumbai, IOC Odisha Campus Bhubaneswar, Bhubaneswar 751013, India
| | - Karan Ramdas Thombare
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Rajasthan 342037, India
| | - Lisa Roy
- Institute of Chemical Technology Mumbai, IOC Odisha Campus Bhubaneswar, Bhubaneswar 751013, India
| | - Sandip Murarka
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Rajasthan 342037, India
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30
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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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31
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Kong X, Chen Y, Chen X, Ma C, Chen M, Wang W, Xu YQ, Ni SF, Cao ZY. Organomediated electrochemical fluorosulfonylation of aryl triflates via selective C-O bond cleavage. Nat Commun 2023; 14:6933. [PMID: 37907478 PMCID: PMC10618246 DOI: 10.1038/s41467-023-42699-0] [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: 06/03/2023] [Accepted: 10/19/2023] [Indexed: 11/02/2023] Open
Abstract
Although aryl triflates are essential building blocks in organic synthesis, the applications as aryl radical precursors are limited. Herein, we report an organomediated electrochemical strategy for the generation of aryl radicals from aryl triflates, providing a useful method for the synthesis of aryl sulfonyl fluorides from feedstock phenol derivatives under very mild conditions. Mechanistic studies indicate that key to success is to use catalytic amounts of 9, 10-dicyanoanthracene as an organic mediator, enabling to selectively active aryl triflates to form aryl radicals via orbital-symmetry-matching electron transfer, realizing the anticipated C-O bond cleavage by overcoming the competitive S-O bond cleavage. The transition-metal-catalyst-free protocol shows good functional group tolerance, and may overcome the shortages of known methods for aryl sulfonyl fluoride synthesis. Furthermore, this method has been used for the modification and formal synthesis of bioactive molecules or tetraphenylethylene (TPE) derivative with improved quantum yield of fluorescence.
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Affiliation(s)
- Xianqiang Kong
- School of Chemical Engineering and Materials, Changzhou Institute of Technology, No. 666 Liaohe Road, 213032, Changzhou, China.
| | - Yiyi Chen
- School of Chemical Engineering and Materials, Changzhou Institute of Technology, No. 666 Liaohe Road, 213032, Changzhou, China
| | - Xiaohui Chen
- School of Chemical Engineering and Materials, Changzhou Institute of Technology, No. 666 Liaohe Road, 213032, Changzhou, China
| | - Cheng Ma
- Department of Chemistry, Shantou University, 515063, Shantou, Guangdong, China
| | - Ming Chen
- Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology, School of Petrochemical Engineering, Changzhou University, 21 Gehu Road, 213164, Changzhou, China
| | - Wei Wang
- School of Chemical Engineering and Materials, Changzhou Institute of Technology, No. 666 Liaohe Road, 213032, Changzhou, China
| | - Yuan-Qing Xu
- College of Chemistry and Molecular Sciences, Henan University, 475004, Kaifeng, China
| | - Shao-Fei Ni
- Department of Chemistry, Shantou University, 515063, Shantou, Guangdong, China.
| | - Zhong-Yan Cao
- College of Chemistry and Molecular Sciences, Henan University, 475004, Kaifeng, China.
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32
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Muralirajan K, Kancherla R, Maity B, Karuthedath S, Laquai F, Cavallo L, Rueping M. Mechanistic insights into excited-state palladium catalysis for C-S bond formations and dehydrogenative sulfonylation of amines. Nat Commun 2023; 14:6622. [PMID: 37857662 PMCID: PMC10587301 DOI: 10.1038/s41467-023-42392-2] [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: 01/31/2023] [Accepted: 10/10/2023] [Indexed: 10/21/2023] Open
Abstract
Photocatalytic selective C(sp3)-H activation/cross-coupling reactions are appealing in organic synthesis. In this manuscript, we describe the development of photoexcited-state Pd-catalyzed dehydrogenative β-sulfonylation reactions using amines and aryl sulfonyl chlorides via intermolecular hydrogen atom transfer and C-S cross-coupling processes at room temperature. The transformation can be achieved by the direct generation of two distinct Pd-radical hybrid species and their capability to promote two different reactivities from Pd(0) and aryl sulfonyl chlorides, allowing for the efficient conversion of readily available amines into stable sulfonyl-substituted enamines at room temperature. The in-depth experimental, computational, and transient optical spectroscopic study and catalytic applications of a dehydrogenative functionalization event provide evidence for both static and dynamic quenching, as well as inner-sphere and outer-sphere mechanisms.
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Affiliation(s)
- Krishnamoorthy Muralirajan
- KAUST Catalysis Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Rajesh Kancherla
- KAUST Catalysis Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Bholanath Maity
- KAUST Catalysis Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Safakath Karuthedath
- KAUST Solar Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Frédéric Laquai
- KAUST Solar Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia.
| | - Luigi Cavallo
- KAUST Catalysis Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia.
| | - Magnus Rueping
- KAUST Catalysis Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia.
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33
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Antolinc K, Brodnik H, Grošelj U, Štefane B, Petek N, Svete J. Catalytic Photoredox C-H Arylation of 4-Oxo-4 H-pyrido[1,2- a]pyrimidine-3-diazonium Tetrafluoroborates and Related Heteroaryl Diazonium Salts. J Org Chem 2023; 88:13934-13945. [PMID: 37676813 PMCID: PMC10563132 DOI: 10.1021/acs.joc.3c01517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Indexed: 09/09/2023]
Abstract
Irradiation of mixtures of title diazonium salts and heteroarenes with green light (510 nm) in the presence of eosin Y disodium salt (EY-Na2) as a photocatalyst furnished the corresponding arylation products in 8-63% yields. The proposed photocatalytic cycle is analogous to that proposed previously for closely related photoredox C-H arylations with aryl diazonium salts as aryl radical sources. This method has a broad substrate scope and represents a metal-free alternative for the synthesis of 3-heteroaryl-substituted 4H-quinolizin-4-ones and azino- and azolo-fused pyrimidones with a bridgehead nitrogen atom.
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Affiliation(s)
- Kris Antolinc
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna Pot 113, SI-1000 Ljubljana, Slovenia
| | - Helena Brodnik
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna Pot 113, SI-1000 Ljubljana, Slovenia
| | - Uroš Grošelj
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna Pot 113, SI-1000 Ljubljana, Slovenia
| | - Bogdan Štefane
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna Pot 113, SI-1000 Ljubljana, Slovenia
| | - Nejc Petek
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna Pot 113, SI-1000 Ljubljana, Slovenia
| | - Jurij Svete
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna Pot 113, SI-1000 Ljubljana, Slovenia
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34
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Liu S, Robert F, Landais Y. Dual photoredox nickel-catalyzed silylation of aryl/heteroaryl bromides using hydrosilanes. Chem Commun (Camb) 2023; 59:11369-11372. [PMID: 37665260 DOI: 10.1039/d3cc03246a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Dual Ni and Ir catalysis enables the preparation of arylsilanes having a (TMS)3Si substituent from the corresponding aryl bromides and (TMS)3SiH at 30 °C using visible-light irradiation. This protocol avoids strong bases, high temperature and air and moisture sensitive silyl reagents, providing the expected arylsilanes in moderate to good yields. The reaction was shown to proceed through a silyl radical, likely generated by hydrogen atom abstraction from (TMS)3SiH by a bromide radical.
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Affiliation(s)
- Shuai Liu
- University Bordeaux, CNRS, Bordeaux INP, ISM, UMR 5255, F-33400 Talence, France.
| | - Frédéric Robert
- University Bordeaux, CNRS, Bordeaux INP, ISM, UMR 5255, F-33400 Talence, France.
| | - Yannick Landais
- University Bordeaux, CNRS, Bordeaux INP, ISM, UMR 5255, F-33400 Talence, France.
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35
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Audet F, Donnard M, Panossian A, Bernier D, Pazenok S, Leroux FR. New Chemical Transformations Involving SO 2 F 2 -Mediated Alcohol Activation. CHEM REC 2023; 23:e202300107. [PMID: 37236146 DOI: 10.1002/tcr.202300107] [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: 03/27/2023] [Revised: 05/02/2023] [Indexed: 05/28/2023]
Abstract
Sulfuryl fluoride is a gas produced on a multi-ton scale for its use as a fumigant. In the last decades, it has gained interest in organic synthesis as a reagent with unique properties in terms of stability and reactivity when compared to other sulfur-based reagents. Sulfuryl fluoride has not only been used for sulfur-fluoride exchange (SuFEx) chemistry but also encountered applications in classic organic synthesis as an efficient activator of both alcohols and phenols, forming a triflate surrogate, namely a fluorosulfonate. A long-standing industrial collaboration in our research group drove our work on the sulfuryl fluoride-mediated transformations that will be highlighted below. We will first describe recent works on metal-catalyzed transformations from aryl fluorosulfonates while emphasizing the one-pot processes from phenol derivatives. In a second section, nucleophilic substitution reactions on polyfluoroalkyl alcohols will be discussed and the value of polyfluoroalkyl fluorosulfonates in comparison to alternative triflate and halide reagents will be brought to light.
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Affiliation(s)
- Florian Audet
- Laboratoire d'Innovation Moléculaire et Applications (UMR7042), Université de Strasbourg, Université de Haute-Alsace, CNRS, 25 rue Becquerel, 67000, Strasbourg, France
| | - Morgan Donnard
- Laboratoire d'Innovation Moléculaire et Applications (UMR7042), Université de Strasbourg, Université de Haute-Alsace, CNRS, 25 rue Becquerel, 67000, Strasbourg, France
| | - Armen Panossian
- Laboratoire d'Innovation Moléculaire et Applications (UMR7042), Université de Strasbourg, Université de Haute-Alsace, CNRS, 25 rue Becquerel, 67000, Strasbourg, France
| | - David Bernier
- Bayer S.A.S., 14 impasse Pierre Baizet, 69263, Lyon, France
| | - Sergii Pazenok
- Bayer CropScience AG, Alfred Nobel Straße 50, 40789, Monheim, Germany
| | - Frédéric R Leroux
- Laboratoire d'Innovation Moléculaire et Applications (UMR7042), Université de Strasbourg, Université de Haute-Alsace, CNRS, 25 rue Becquerel, 67000, Strasbourg, France
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36
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Maity A, Studer A. 1,2-Aminoxyalkylation of alkenes with alkyl iodides and TEMPONa through SET- and XAT-processes. Chem Sci 2023; 14:7675-7680. [PMID: 37476718 PMCID: PMC10355098 DOI: 10.1039/d3sc02544f] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 06/23/2023] [Indexed: 07/22/2023] Open
Abstract
1,2-Aminoxyalkylation of alkenes with alkyl iodides and TEMPONa in combination with an aryldiazonium salt as an XAT mediator is reported. Various primary, secondary and tertiary alkyl iodides engage as C-radical precursors in the 1,2-aminoxyalkylation with electrophilic alkenes as radical acceptors. The product alkoxyamines are readily transformed to the corresponding alcohols or ketones upon reduction or oxidation, respectively. Mechanistic investigations reveal that aryl radicals, generated through SET-reduction of the aryl diazonium salt with TEMPONa, engage in XAT from unactivated alkyl halides to give alkyl radicals that can add to alkenes. Trapping of the adduct radicals with TEMPO provides the 1,2-aminoxyalkylation products. Transition metals are not required for these transformations that are conducted under mild conditions. Perfluoroalkyl halides directly react with TEMPONa and an aryldiazonium salt as XAT-mediator is not required for alkene 1,2-aminoxyperfluoroalkylation.
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Affiliation(s)
- Anirban Maity
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Corrensstraße 40 48149 Munster Germany
| | - Armido Studer
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Corrensstraße 40 48149 Munster Germany
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37
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van Dalsen L, Brown RE, Rossi‐Ashton JA, Procter DJ. Sulfonium Salts as Acceptors in Electron Donor-Acceptor Complexes. Angew Chem Int Ed Engl 2023; 62:e202303104. [PMID: 36959098 PMCID: PMC10952135 DOI: 10.1002/anie.202303104] [Citation(s) in RCA: 28] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 03/22/2023] [Accepted: 03/23/2023] [Indexed: 03/25/2023]
Abstract
The photoactivation of electron donor-acceptor complexes has emerged as a sustainable, selective and versatile strategy for the generation of radical species. Electron donor-acceptor (EDA) complexation, however, imposes electronic constraints on the donor and acceptor components and this can limit the range of radicals that can be generated using the approach. New EDA complexation strategies exploiting sulfonium salts allow radicals to be generated from native functionality. For example, aryl sulfonium salts, formed by the activation of arenes, can serve as the acceptor components in EDA complexes due to their electron-deficient nature. This "sulfonium tag" approach relaxes the electronic constraints on the parent substrate and dramatically expands the range of radicals that can be generated using EDA complexation. In this review, these new applications of sulfonium salts will be introduced and the areas of chemical space rendered accessible through this innovation will be highlighted.
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Affiliation(s)
| | - Rachel E. Brown
- Department of ChemistryThe University of ManchesterManchesterUK
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38
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Vincent CA, Ripak A, Troian-Gautier L, Tambar UK. Photocatalytic conversion of aryl diazonium salts to sulfonyl fluorides. Tetrahedron 2023; 139:133364. [PMID: 38404686 PMCID: PMC10887421 DOI: 10.1016/j.tet.2023.133364] [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] [Indexed: 02/27/2024]
Abstract
Sulfonyl fluorides have emerged as powerful tools in chemical biology for the selective labelling of proteins. A photocatalytic method is described for the conversion of aryl diazonium salts to aryl sulfonyl fluorides. The diazonium substrates are easily obtained in one step from functionalized anilines. We present the optimization of this mild method for the synthesis of sulfonyl fluorides, the scope of the transformation with a series of functionalized diazonium salts, and we discuss photophysical measurements that provide detailed information about the mechanism of the photochemical process.
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Affiliation(s)
- Cooper A. Vincent
- Department of Biochemistry, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-9038, United States
| | - Alexia Ripak
- Université Catholique de Louvain (UCLouvain), Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST), Place Louis Pasteur 1, bte L4.01.02, 1348, Louvain-la-Neuve, Belgium
| | - Ludovic Troian-Gautier
- Université Catholique de Louvain (UCLouvain), Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST), Place Louis Pasteur 1, bte L4.01.02, 1348, Louvain-la-Neuve, Belgium
| | - Uttam K. Tambar
- Department of Biochemistry, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-9038, United States
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39
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Piedra HF, Valdés C, Plaza M. Shining light on halogen-bonding complexes: a catalyst-free activation mode of carbon-halogen bonds for the generation of carbon-centered radicals. Chem Sci 2023; 14:5545-5568. [PMID: 37265729 PMCID: PMC10231334 DOI: 10.1039/d3sc01724a] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 05/03/2023] [Indexed: 06/03/2023] Open
Abstract
The discovery of new activation modes for the creation of carbon-centered radicals is a task of great interest in organic chemistry. Classical activation modes for the generation of highly reactive radical carbon-centered intermediates typically relied on thermal activation of radical initiators or irradiation with unsafe energetic UV light of adequate reaction precursors. In recent years, photoredox chemistry has emerged as a leading strategy towards the catalytic generation of C-centered radicals, which enabled their participation in novel synthetic organic transformations which is otherwise very challenging or even impossible to take place. As an alternative to these activation modes for the generation of C-centered radicals, the pursuit of greener, visible-light initiated reactions that do not necessitate a photoredox/metal catalyst has recently caught the attention of chemists. In this review, we covered recent transformations, which rely on photoactivation with low-energy light of a class of EDA complexes, known as halogen-bonding adducts, for the creation of C-centered radicals.
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Affiliation(s)
- Helena F Piedra
- Departamento de Química Orgánica e Inorgánica, Instituto Universitario de Química Organometálica "Enrique Moles" and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Oviedo Julián Clavería 8 33006 Oviedo Spain
| | - Carlos Valdés
- Departamento de Química Orgánica e Inorgánica, Instituto Universitario de Química Organometálica "Enrique Moles" and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Oviedo Julián Clavería 8 33006 Oviedo Spain
| | - Manuel Plaza
- Departamento de Química Orgánica e Inorgánica, Instituto Universitario de Química Organometálica "Enrique Moles" and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Oviedo Julián Clavería 8 33006 Oviedo Spain
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40
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Botla V, Fontana M, Voronov A, Maggi R, Motti E, Maestri G, Della Ca' N. Closing the Cycle as It Begins: Synthesis of
ortho
‐Iodobiaryls via Catellani Reaction. Angew Chem Int Ed Engl 2023. [DOI: 10.1002/ange.202218928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
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41
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Lin Q, Spielvogel EH, Diao T. Carbon-centered radical capture at nickel(II) complexes: Spectroscopic evidence, rates, and selectivity. Chem 2023. [DOI: 10.1016/j.chempr.2023.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/15/2023]
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42
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Zhang X, Shen Y, Rovis T. Photoinduced Nickel-Catalyzed Selective N-Demethylation of Trialkylamines Using C(sp 2)-Bromides as HAT Reagents. J Am Chem Soc 2023; 145:3294-3300. [PMID: 36724205 PMCID: PMC9997100 DOI: 10.1021/jacs.2c12767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
N-Demethylation of trialkylamines is a useful transformation, but typically requires harsh reaction conditions and stepwise procedures, as well as judicious protection of labile functional groups. Herein we report a mild, catalytic approach for the demethylation of trialkylamines by utilizing photoinduced nickel catalysis wherein C(sp2)-bromides serve as hydrogen-atom transfer (HAT) reagents. This method achieves direct demethylation of trialkylamines with wide functional group compatibility, making it highly suitable for late-stage derivatization of complex molecules. Mechanistic investigations provide evidence that C(sp2) radicals generated via photoinduced Ni-C(sp2) bond homolysis are involved in hydrogen atom abstraction from trialkylamines. Utilizing steric control of the C(sp2)-bromides, our HAT approach achieves demethylation with excellent site selectivity in the presence of benzyl-substituted amines, which is complementary to the selectivity of classical approaches that afford debenzylation product instead.
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Affiliation(s)
- Xiao Zhang
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Yangyang Shen
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Tomislav Rovis
- Department of Chemistry, Columbia University, New York, New York 10027, United States
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Majhi J, Granados A, Matsuo B, Ciccone V, Dhungana RK, Sharique M, Molander GA. Practical, scalable, and transition metal-free visible light-induced heteroarylation route to substituted oxindoles. Chem Sci 2023; 14:897-902. [PMID: 36755706 PMCID: PMC9890556 DOI: 10.1039/d2sc05918e] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 12/19/2022] [Indexed: 01/04/2023] Open
Abstract
The synthetic application of (hetero)aryl radicals in organic synthesis has been known since the last century. However, their applicability has significantly suffered from ineffective generation protocols. Herein, we present a visible-light-induced transition metal-free (hetero)aryl radical generation from readily available (hetero)aryl halides for the synthesis of 3,3'-disubstituted oxindoles. This transformation is amenable to a wide range of (hetero)aryl halides as well as several easily accessible acrylamides, and it is also scalable to multigram synthesis. Finally, the versatility of the oxindole products is demonstrated through their conversion to a variety of useful intermediates applicable to target-directed synthesis.
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Affiliation(s)
- Jadab Majhi
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104-6323 USA
| | - Albert Granados
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104-6323 USA
| | - Bianca Matsuo
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104-6323 USA
| | - Vittorio Ciccone
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104-6323 USA
| | - Roshan K Dhungana
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104-6323 USA
| | - Mohammed Sharique
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104-6323 USA
| | - Gary A Molander
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104-6323 USA
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Das R, Kundu T, Basumatary J. Visible light mediated organocatalytic dehydrogenative aza-coupling of 1,3-diones using aryldiazonium salts. RSC Adv 2023; 13:3147-3154. [PMID: 36756411 PMCID: PMC9853514 DOI: 10.1039/d2ra07807d] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 01/03/2023] [Indexed: 01/21/2023] Open
Abstract
An efficient protocol for diazenylation of 1,3-diones under photoredox conditions is presented herein. C-N bond forming Csp3 -H functionalization of cyclic and alkyl diones by unstable aryl diazenyl radicals is achieved through reaction with aryldiazonium tetrafluoroborates by organocatalysts under visible light irradiation. The reaction has wide substrate scope, gives excellent yields, and is also efficient in water as a green solvent. This method provides an easy access to aryldiazenyl derivatives that are useful key starting materials for the synthesis of aza heterocycles as well as potential pharmacophores.
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Affiliation(s)
- Ramanand Das
- Department of Chemistry, National Institute of Technology Sikkim Ravangla, South Sikkim PIN 737139 India
| | - Taraknath Kundu
- Department of Chemistry, National Institute of Technology Sikkim Ravangla, South Sikkim PIN 737139 India
| | - Joneswar Basumatary
- Department of Chemistry, Sikkim University Tadong, Daragaon, East Sikkim Gangtok PIN 737102 India
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Cai Y, Ritter T. Meerwein-type Bromoarylation with Arylthianthrenium Salts. Angew Chem Int Ed Engl 2022; 61:e202209882. [PMID: 36070220 PMCID: PMC9828184 DOI: 10.1002/anie.202209882] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Indexed: 01/12/2023]
Abstract
Herein, we report a photocatalyzed Meerwein-type bromoarylation of alkenes with stable arylthianthrenium salts, formed by site-selective C-H thianthrenation. This protocol can be applied to late-stage functionalization of a variety of biomolecules that are difficult to access by other aryl coupling reagents. Halogen introduction allows for a variety of follow-up transformations, affording numerous biologically active skeletons.
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Affiliation(s)
- Yuan Cai
- Max-Planck-Institut für KohlenforschungKaiser-Wilhelm-Platz 145470Mülheim an der RuhrGermany
| | - Tobias Ritter
- Max-Planck-Institut für KohlenforschungKaiser-Wilhelm-Platz 145470Mülheim an der RuhrGermany
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46
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Panferova LI, Zubkov MO, Kosobokov MD, Dilman AD. Light-Promoted Dearylation of Perfluorinated Aryl Sulfides with N-Heterocyclic Carbene–Borane. Org Lett 2022; 24:8559-8563. [DOI: 10.1021/acs.orglett.2c03585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Liubov I. Panferova
- N.D. Zelinsky Institute of Organic Chemistry, Leninsky Prospekt 47, 119991 Moscow, Russian Federation
| | - Mikhail O. Zubkov
- N.D. Zelinsky Institute of Organic Chemistry, Leninsky Prospekt 47, 119991 Moscow, Russian Federation
| | - Mikhail D. Kosobokov
- N.D. Zelinsky Institute of Organic Chemistry, Leninsky Prospekt 47, 119991 Moscow, Russian Federation
| | - Alexander D. Dilman
- N.D. Zelinsky Institute of Organic Chemistry, Leninsky Prospekt 47, 119991 Moscow, Russian Federation
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47
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Marchese AD, Durant AG, Reid CM, Jans C, Arora R, Lautens M. Pd(0)/Blue Light Promoted Carboiodination Reaction – Evidence for Reversible C–I Bond Formation via a Radical Pathway. J Am Chem Soc 2022; 144:20554-20560. [DOI: 10.1021/jacs.2c09716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Austin D. Marchese
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario Canada, M5S 3H6
| | - Andrew G. Durant
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario Canada, M5S 3H6
| | - Cian M. Reid
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario Canada, M5S 3H6
| | - Clara Jans
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario Canada, M5S 3H6
| | - Ramon Arora
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario Canada, M5S 3H6
| | - Mark Lautens
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario Canada, M5S 3H6
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48
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Folgueiras‐Amador AA, Teuten AE, Salam‐Perez M, Pearce JE, Denuault G, Pletcher D, Parsons PJ, Harrowven DC, Brown RCD. Cathodic Radical Cyclisation of Aryl Halides Using a Strongly-Reducing Catalytic Mediator in Flow. Angew Chem Int Ed Engl 2022; 61:e202203694. [PMID: 35790060 PMCID: PMC9543573 DOI: 10.1002/anie.202203694] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Indexed: 11/13/2022]
Abstract
Electro-reductive radical cyclisation of aryl halides affords the corresponding hetero- and carbo-cycles in an undivided flow reactor equipped with steel and carbon electrodes using an organic mediator. A dissolving metal anode is not needed, and the mediator can be employed in a sub-stoichiometric amount (0.05 equiv), increasing the practical utility of cathodic radical cyclisation. The methodology is applied to O-, N-, and C-tethers, yielding tricyclic fused and spiro systems. In the absence of mediator, the major pathway is hydrogenolysis of the C-X bond, a 2 e- process occurring at the cathode. Predominance of the radical pathway in presence of a strongly reducing mediator (M) is consistent with homogeneous electron-transfer in a reaction layer detached from the cathode surface, where the flux of M.- leaving the electrode is such that little aryl halide reaches the cathode.
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Affiliation(s)
| | | | - Mateo Salam‐Perez
- School of ChemistryUniversity of SouthamptonHighfieldSouthamptonSO17 1BJUK
| | - James E. Pearce
- School of ChemistryUniversity of SouthamptonHighfieldSouthamptonSO17 1BJUK
| | - Guy Denuault
- School of ChemistryUniversity of SouthamptonHighfieldSouthamptonSO17 1BJUK
| | - Derek Pletcher
- School of ChemistryUniversity of SouthamptonHighfieldSouthamptonSO17 1BJUK
| | - Philip J. Parsons
- Department of ChemistryImperial College LondonWhite City CampusLondonW12 0BZUK
| | - David C. Harrowven
- School of ChemistryUniversity of SouthamptonHighfieldSouthamptonSO17 1BJUK
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Visible-Light Photocatalytic Reduction of Aryl Halides as a Source of Aryl Radicals. Molecules 2022; 27:molecules27175364. [PMID: 36080129 PMCID: PMC9458128 DOI: 10.3390/molecules27175364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 08/19/2022] [Accepted: 08/20/2022] [Indexed: 11/17/2022] Open
Abstract
Aryl- and heteroaryl units are present in a wide variety of natural products, pharmaceuticals, and functional materials. The method for reduction of aryl halides with ubiquitous distribution is highly sought after for late-stage construction of various aromatic compounds. The visible-light-driven reduction of aryl halides to aryl radicals by electron transfer provides an efficient, simple, and environmentally friendly method for the construction of aromatic compounds. This review summarizes the recent progress in the generation of aryl radicals by visible-light-driven reduction of aryl halides with metal complexes, organic compounds, semiconductors as catalysts, and alkali-assisted reaction system. The ability and mechanism of reduction of aromatic halides in various visible light induced systems are summarized, intending to illustrate a comprehensive introduction of this research topic to the readers.
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Samanta RK, Meher P, Murarka S. Visible Light Photoredox-Catalyzed Direct C-H Arylation of Quinoxalin-2(1 H)-ones with Diaryliodonium Salts. J Org Chem 2022; 87:10947-10957. [PMID: 35925769 DOI: 10.1021/acs.joc.2c01234] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A photoredox-catalyzed direct arylation of quinoxalin-2-(1H)-ones using diaryliodonium triflates as the convenient, stable, and cheap aryl source is described. A broad variety of quinoxalin-2-(1H)-ones are shown to react with structurally and electronically diverse diaryliodonium triflates, allowing efficient access to a wide variety of pharmaceutically important 3-arylquinoxalin-2-(1H)-ones. The presented method is attractive with regard to operational simplicity, mild conditions, broad scope, scalability, and high functional group tolerance.
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Affiliation(s)
- Raj K Samanta
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Rajasthan 342037, India
| | - Prahallad Meher
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Rajasthan 342037, India
| | - Sandip Murarka
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Rajasthan 342037, India
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