Rhodium catalyzed template-assisted distal para-C-H olefination.

Rhodium catalysis has been extensively used for ortho-C-H functionalization reactions, and successfully extended to meta-C-H functionalization. Its application to para-C-H activation remains an unmet challenge. Herein we disclose the first example of such a reaction, with the Rh-catalyzed para-C-H olefination of arenes. The use of a Si-linked cyanobiphenyl unit as a traceless directing group leads to highly para-selective arene-olefin couplings.