Synthesis of the biaryl moiety of the proteasome inhibitors TMC-95 via a ligandless Pd(OAc)2-catalyzed Suzuki-coupling reaction

The biaryl moiety of proteasome inhibitors TMC-95 was synthesized via a Pd(OAc)2-catalyzed Suzuki-coupling reaction of 7-iodoisatin and a tyrosine-derived arylboronic acid in the absence of phosphine ligands using potassium fluoride as a base.