Palladium-Catalyzed C–H Heteroarylation of 2,5-Disubstituted Imidazoles

Abstract

We developed a palladium-catalyzed C–H N-heteroarylation of N-protected-2,5-disubstituted imidazoles at the C4-position using N-heteroaryl halides as a coupling partner. Intensive reaction condition screening led us to identify fluorinated bathophenanthroline 7 as the optimum ligand for the palladium catalyst. This reaction will enhance lead optimization of drug candidates by facilitating the synthesis of heterobiaryl compounds containing an imidazole ring.