Expedient, Directed Ir-Catalyzed Diborylation of (Hetero)Biaryls via a Tridentate Ligand

Abstract The expedient iridium-catalyzed diborylation of 2-aryl pyridines and isoquinolines with bis(pinacolato)diboron (B2pin2) is reported. Utilizing [Ir(OMe)(COD)]2 and a terpyridine derivate as tridentate ligand, which are rarely used for directed C─H borylation, the heterobiaryls were selectively diborylated in the 2,6-position of the carbocycle. The developed method shows exceptional high activity as well as regioselectivity with low catalyst loading.