Origin of ligand-controlled regioselectivity in Co-catalyzed borylation of fluorinated arenes

Abstract

The mechanism and origins of regioselectivity in cobalt-catalyzed borylation of fluorinated arenes were computationally investigated. The results reveal that cobalt catalysts bearing two distinct pincer ligands exhibit different regioselectivity-determining steps. The ortho-selective borylation observed with the (PNP)Co catalyst is attributed to stronger electronic interactions in the σ-bond metathesis transition state. In contrast, the meta-selective borylation favored by the (CNC)Co catalyst arises from weaker electrostatic repulsion and enhanced charge transfer effects in the C–H oxidative addition transition state.