Aryl Radical-Initiated Synthesis of Unsymmetrically Bicyclo[1.1.1]pentane Sulfides

Here, we developed an efficient halogen atom transfer (XAT)-enabled multicomponent reaction (MCR) between [1.1.1]propellane, zinc thiolates, and alkyl iodides utilizing aryldiazonium salt as the promoter. Moreover, direct aryl-thiolation of [1.1.1]propellane in the absence of alkyl iodides was also described. Thus, these chemoselective reactions provide a practical approach to construct a variety of aryl- or alkyl-substituted BCP-sulfides under mild reaction conditions. Mechanistic studies support that the aryl radical generated by the interaction between aryldiazonium salt and zinc thiolate undergoes a rapid XAT process to deliver the corresponding alkyl radical. Notably, the bench-stable zinc thiolates play dual roles, including the initiator of aryl radical and coupling partner.