MeOH-Triggered Halogen-Atom Transfer of Unactivated Alkyl Bromides Enabling the Photoredox Giese Addition
Xian-Chen He1, Yan-Ling Liu1, Jie Gao1
1College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, P. R. China.
Abstract:
Herein, a nickel-catalyzed, photoredox Giese addition reaction with readily accessible alkyl bromides, driven by readily available feedstock MeOH as the halogen-atom transfer (XAT) reagent, was successfully achieved under mild conditions. The versatility of this protocol was demonstrated through a range of structurally varied alkyl bromides and Giese-type acceptors with moderate to good yields. Mechanistic investigation highlights that the formation of alkyl radicals through the XAT of alkyl bromides was tentatively prompted by •CH2OH, which was derived from the sequential photo-oxidation/1,2-hydrogen-atom transfer of MeOH.
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