Mechanistic insights into Ni-catalyzed hydrogen atom transfer (HAT)-triggered hydrodefluorination of CF3-substituted
Jiandong Guo1, Dongju Zhang2, Xiaotai Wang3
1Hoffmann Institute of Advanced Materials, Postdoctoral Innovation Practice Base, Shenzhen Polytechnic, 7098 Liuxian Boulevard, Nanshan District, Shenzhen 518055, P. R. China and Institute of Theoretical Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China.
Abstract:
We report the first computational study on a nickel hydride HAT-initiated catalytic reaction, a novel hydrodefluorination of CF3-substituted aryl alkenes to afford gem-difluoroalkenes. This study provides detailed mechanistic insights into the reaction, including HAT from NiH to C[double bond, length as m-dash]C, a carbon radical rebound to nickel to facilitate chemoselective defluorination, and a two-state reactivity of Ni(ii) enabling σ-bond metathesis with PhSiH3 to regenerate the catalyst. The findings can have implications for developing new metal hydride HAT-initiated reactions.
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