TBHP-mediated photochemical coupling/cyclization of -arylacrylamides with thiols

The effective photoredox-mediated oxidative thiolation and cyclization of N -arylacrylamides with thiols leads to biologically interesting 3-thionated oxindoles through C-S and C-C bond formation. This process represents a straightforward reaction that starts from non-prefunctionalized thiolating reagents. Mechanistic studies demonstrated that the TBHP serves as a key radical initiator with visible-light catalysis. TBHP-mediated thiyl couplings: A mild and metal-free visible-light-induced system allows sequential thiolation/cyclization of N -aryl acrylamides and mercaptans and provides an access to thionated oxindoles with potential biological activity.