Highly efficient and versatile synthesis of polyarylfluorenes via Pd-catalyzed C-H bond activation.

A facile protocol for the Pd-catalyzed preparative synthesis of fluorene derivatives has been developed. While a wide range of fluorenes were easily obtained with high efficiency and selectivity under mild conditions, excellent functional group tolerance was also demonstrated. On the basis of Hammett and KIE studies, the present reaction is proposed to proceed via a base-assisted deprotonative metalation pathway.