Efficient Route to 1,3-Di-<i>N</i>-imidazolylbenzene. A Comparison of Monodentate vs Bidentate Carbenes in Pd-Catalyzed Cross Coupling

Abstract

A new bis(carbene) ligand architecture has been developed and was evaluated in the Suzuki-Miyaura cross-coupling reaction of various aryl halides with phenylboronic acid. Several new bis(carbene) ligands were tested in different carbene:Pd ratios. Pd(OAc)(2) and Pd(2)(dba)(3) were compared for efficiency as a Pd source. It was found that the Pd(OAc)(2)/bis(carbene) system formed a catalyst for the activation of chlorobenzene. [reaction: see text]