Scaled-up Negishi-Coupling of Aryl Halides Bearing Unprotected Amides with Knochel-Type Organozinc Reagents

Abstract

Without the need of any protecting groups, aryl halides bearing acidic amides were coupled with several Knochel-type organozinc reagents by using Pd(OAc)2 as catalyst and 2-dicyclohexylphosphino-2’,6'-dimethoxy biphenyl (S-Phos) as ligand. The reactions were carried out on a large scale (30 mmol), furnishing the desired coupling products smoothly in excellent yields (70–98%).