Remote arylalkylation of unactivated alkenes via 6- or 7-membered nickelacycles with excellent diastereofidelity

Abstract

Herein, we report a nickel-catalyzed remote arylalkylation of unactivated γ,δ- and δ,ε-alkenes in alkenyl carbonyl compounds with arylboronic acids and alkyl halides. Kinetically and thermodynamically disfavored 6- and 7-membered nickelacycles were stabilized by the 8-aminoquinoline directing group and subsequent intercepted by the alkyl halides to achieve remote arylalkylation. The practical protocol was compatible with α- or β-substituted terminal alkenes and internal alkenes, providing rapid access to branched molecules bearing two skipped and vicinal stereocenters with high diastereoselectivity (most >20 : 1 dr). Moreover, the radical-based Ni^I–Ni^III–Ni^I catalytic cycle was suggested by combined experimental and density functional theory (DFT) computational studies to understand the mechanism and diastereoselectivity.