The first example of cobalt-catalyzed C(sp 2 )ÀH carbonylation of benzylamines using a traceless directing group is reported, which was successfully applied to the synthesis of NÀunprotected iso-indolinones through direct CÀH/NÀH bonds activation. This protocol tolerates a variety of functional groups and provides a facile and efficient method for the formal synthesis of (+)-garenoxacin.

A traceless directing group assisted Co-catalyzed C(sp)-H carbonylation of ortho-arylanilines for the synthesis of free ( NH)-phenanthridinones in metal-based-oxidant-free fashion was accomplished. This protocol employs diisopropyl azodicarboxylate as the CO source and oxygen as the sole oxidant, and provides good yields with various functional tolerance. The methodology has been applied for the total synthesis of PARP inhibitor PJ-34. Furthermore, the kinetic isotopic effect experiments reveal the C-H bond cleavage probably occurred in the rate-determining step.

An eco-friendly electrochemical synthesis of sulfinic esters from thiols and alcohols under mild reaction conditions has been developed.