Palladium-Catalyzed Direct C-H Silylation and Germanylation of Benzamides and Carboxamides

A palladium-catalyzed regioselective activation of C(sp(2))-H and C(sp(3))-H bonds of benzamides and carboxamides, followed by coupling with disilanes to afford organosilanes in moderate to high yields, with the aid of 8-aminoquinoline as a directing group, is reported. Catalytic C(sp(2))-H germanylation of benzamides also proceeds under the same palladium catalysis. The reaction tolerates a wide variety of functional groups and is scalable without yield reduction. The bidentate directing group is readily removed and recovered by the reaction with a hydrazine, with concominant generation of an acyl hydrazide.