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![[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
Photoredox/Copper Catalysis Enables C(sp3)-S Coupling of Alkyl Boronic Esters via Aminyl Radical Transfer
Swapan Shil1, Bishnu Pada Patra1, Srikrishna Bera1
1Department of Chemistry, Indian Institute of Technology Tirupati, Tirupati 517619, Andhra Pradesh, India.
Abstract:
A dual photoredox/copper catalytic strategy for C(sp3)-S coupling between alkyl boronic esters (alkyl Bpins) and sulfenamides via aminyl radical transfer (ART) is described. The strategy achieves chemoselective C-S bond formation while suppressing competing S-N coupling pathways and enables the streamlined access to valuable sulfilimine products. A broad range of primary, secondary, tertiary, and strained alkyl boronic esters are compatible substrates. Mechanistic studies support a radical transmetalation pathway involving ART activation and copper-mediated coupling.
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