Palladium-Catalyzed γ-C(sp3)-H Arylation of Thiols by a Detachable Protecting/Directing Group

Reported herein is a palladium-catalyzed, directed gamma-C(sp(3))-H arylation of protected thiols. The key is to utilize Michael acceptors as a dual reagent to install a protecting/directing group on thiols by a thiol-Michael click reaction, and remove it later under basic conditions. The C-H arylation proceeds with high functional-group tolerance and the deprotected thiols can be further transformed into other sulfur-containing compounds. This unique mode of activation could open the door for site-selective functionalization of thiols or other sulfur-containing compounds at unactivated positions.