Directing Group Participated Benzylic C(sp3)-H/C(sp2)-H Cross-Dehydrogenative Coupling (CDC): Synthesis of Azapolycycles.

An efficient method to construct azapolycycles via directing group participated benzylic C(sp3)-H/C(sp2)-H cross-dehydrogenative coupling reactions is described. The reaction proceeded through a palladium catalyzed C(sp3)-H activation followed by coupling with a C(sp2)-H bond of quinoline to afford the azapolycyclic compounds. The reaction works with a broad substrate scope affording the products in moderate to good yields with excellent diastereoselectivities. Control experiments further supported the proposed mechanism.