Palladium-catalyzed direct C-H silylation and germanylation of benzamides and carboxamides
A palladium-catalyzed regioselective activation of C(sp2)-H and C(sp3)-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.