Insights into the mechanism and regioselectivity in Ni-catalysed redox-relay migratory hydroarylation of alkenes with arylborons.

DFT studies reveal that Ni-catalysed redox-relay hydroarylation of alkenes occurs via concerted hydronickelation, iterative β-H elimination/migratory insertion and reductive elimination to yield the α-substituted product. The driving force for the redox-relay migratory hydroarylation arises from the stability of the LArNi(II)CHPhPr intermediate, which only allows its C-C elimination pathway to be opened up.