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Lux DM, Lee DJ, Sapkota RR, Giri R. Iron-Mediated Dialkylation of Alkenylarenes with Benzyl Bromides. J Org Chem 2024. [PMID: 38572911 DOI: 10.1021/acs.joc.3c02548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2024]
Abstract
We disclose a method for the dibenzylation of alkenylarenes with benzyl bromides using iron powder. This reaction generates branched alkyl scaffolds adorned with functionalized aryl rings through the formation of two new C(sp3)-C(sp3) bonds at the vicinal carbons of alkenes. This protocol tolerates electron-rich, electron-neutral, and electron-poor benzyl bromides and alkenylarenes. Mechanistic studies suggest the formation of benzylic radical intermediates as a result of single-electron transfer from the iron, which is intercepted by alkenylarenes.
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Affiliation(s)
- Daniel M Lux
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Daniel J Lee
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Rishi R Sapkota
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Ramesh Giri
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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Lu L, Sui J, Huang S, Xiong B, Zeng X, Qiu X, Zhang Y. Nickel-Catalyzed 8-Aminoquinoline Directed Reductive Dialkylcyclization/Homodialkylation of Unactivated Alkenes. Org Lett 2023; 25:7800-7804. [PMID: 37874767 DOI: 10.1021/acs.orglett.3c02955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2023]
Abstract
Chemo and regioselective dialkylation of alkene is an efficient protocol for constructing useful chemicals, but challenges remain in the unrestricted application of alkylating reagents. Alkyl bromide belongs to the easy-to-access and operable alkyl electrophiles that can be used in reductive coupling with alkenes. Here, we reported convenient strategies for dialkylcyclization and homodialkylation of unactivated β,γ- and γ,δ-unsaturated alkenyl amides with 1,3-dibromoalkanes or primary alkyl bromides under nickel-catalyzed reductive conditions that exhibited high regioselectivity and functional-group tolerance.
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Affiliation(s)
- Lingyi Lu
- Nantong Key Laboratory of Small Molecular Drug Innovation, School of Pharmacy, Nantong University, 19 Qixiu Road, Nantong 226001, China
| | - Jing Sui
- Nantong Key Laboratory of Small Molecular Drug Innovation, School of Pharmacy, Nantong University, 19 Qixiu Road, Nantong 226001, China
| | - Shanshan Huang
- Nantong Key Laboratory of Small Molecular Drug Innovation, School of Pharmacy, Nantong University, 19 Qixiu Road, Nantong 226001, China
| | - Biao Xiong
- Nantong Key Laboratory of Small Molecular Drug Innovation, School of Pharmacy, Nantong University, 19 Qixiu Road, Nantong 226001, China
| | - Xiaobao Zeng
- Nantong Key Laboratory of Small Molecular Drug Innovation, School of Pharmacy, Nantong University, 19 Qixiu Road, Nantong 226001, China
| | - Xiaodong Qiu
- Nantong Key Laboratory of Small Molecular Drug Innovation, School of Pharmacy, Nantong University, 19 Qixiu Road, Nantong 226001, China
| | - Yanan Zhang
- Nantong Key Laboratory of Small Molecular Drug Innovation, School of Pharmacy, Nantong University, 19 Qixiu Road, Nantong 226001, China
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3
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Hewitt KA, Herbert CA, Jarvo ER. Synthesis of Vicinal Carbocycles by Intramolecular Nickel-Catalyzed Conjunctive Cross-Electrophile Coupling Reaction. Org Lett 2022; 24:6093-6098. [PMID: 35926218 PMCID: PMC9396665 DOI: 10.1021/acs.orglett.2c02481] [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] [Indexed: 11/30/2022]
Abstract
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A nickel-catalyzed intramolecular conjunctive cross-electrophile
coupling reaction has been established. This method enables the synthesis
of 3,5-vicinal carbocyclic rings found in numerous biologically active
compounds and natural products. We provide mechanistic experiments
that indicate this reaction proceeds through alkyl iodides formed
in situ, initiates at the secondary electrophilic center, and proceeds
through radical intermediates.
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Affiliation(s)
- Kirsten A Hewitt
- Department of Chemistry, University of California, Irvine, California 92617, United States
| | - Claire A Herbert
- Department of Chemistry, University of California, Irvine, California 92617, United States
| | - Elizabeth R Jarvo
- Department of Chemistry, University of California, Irvine, California 92617, United States
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