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

摘要

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).