Redox-Neutral Nickel(II) Catalysis: Hydroarylation of Unactivated Alkenes with Arylboronic Acids
Dao-Ming Wang1, Wang Feng1, Yichen Wu1
1State key laboratory of organometallic chemistry, Center for excellence in molecular synthesis, Shanghai Institute of Organic Chemistry, CAS, 345 Lingling Road, Shanghai, 200032, P. R. China.
Abstract:
Reported here is the discovery of a redox-neutral NiII /NiII catalytic cycle which is capable of the linear-selective hydroarylation of unactivated alkenes with arylboronic acids for the first time. This novel catalytic cycle, enabled by the use of an electron-rich diimine ligand, features broad substrate scope, and excellent functional-group and heterocycle compatibility under mild reaction conditions in the absence of additional oxidants and reductants. Mechanistic investigations using kinetic analysis and deuterium-labelling experiments revealed the protonation to be the rate-determining step in this redox-neutral catalysis, and the reversible chain-walking nature of the newly developed diimine-Ni catalyst.
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