Transmetalation of Ar1ZnX with [Ar2–Pd–X] is the rate-limiting step: kinetic insights from a live Pd-catalyzed Negishi coupling

Abstract

Transmetalation is the rate-limiting step in Negishi coupling: in a live “Pd-catalyzed Negishi coupling of ArI with Ar′ZnX”, the transmetalation was assigned as the rate-limiting step through kinetic investigation. Quantitative measurements of the transmetalation of ArZnX with [Ar–Pd–X] from this live Pd-catalyzed coupling reaction were obtained and the activation enthalpy is 11.3 kcal mol⁻¹.