A novel pyridine-bridged bis-benzimidazolylidene pincer palladium complex:: Synthesis and catalytic properties

A novel pyridine-bridged bis-benzimidazolylidene CNC pincer complex 1 was synthesized from cheap, commercially available precursors under microwave assistance in moderate yield. It catalyzes cross-coupling reactions of aryl halides with alkyl acrylates (Heck reaction) and phenylboronic acid (Suzuki reaction) under aerobic conditions with extremely high turn-over numbers (frequencies) indicating that a planar extension of the pi-system by henzannelation significantly increases the catalytic activity even with trace amounts of catalyst loading.