En Route to N -α-Silylated Thioureas via Iridium-Catalyzed C(sp ³ )–H Silylation

Despite recent advances in the C(sp³)-H bond functionalization of ureas, the targeted C(sp³)-H bond functionalization of thioureas remains a challenge. Herein, we report a simple iridium catalytic system that facilitates the silylation of primary and secondary N-α-C(sp³)-H bonds in thiourea derivatives using hydrosilanes, affording a broad range of mono- and bis-α-silyl-functionalized thioureas in moderate to excellent yields. The directing effect of the intrinsic thiocarbonyl group was pivotal to this silylation. The synthetic potential was demonstrated by a gram-scale reaction and the derivatization of α-silylated thioureas.