Fluoroarylation of gem-difluorostyrenes through a Pd-catalysed aryl C–H bond activation cascade

Abstract

We describe here a novel fluoroarylation of gem-difluorostyrenes with AgF and (hetero)arenes through a Pd(II)-catalysed C(aryl)–H activation cascade. 9-CF₃-substituted fluorenes could be readily obtained through an intramolecular C–H activation/annulation. The challenging intermolecular fluoroarylation of gem-difluorostyrenes could also be achieved with AgF and thiophenes. The reaction obviates the use of pre-functionalised arylating reagents and external ligands, providing an efficient method to access CF₃-substituted 1,1-diarylmethanes.