Dual Role of Sulfenamides in Iodine/Oxone-Catalyzed Three-Component Coupling of 2-Mercaptobenzoxazoles, Amines, and Ketones: Route toward α-Thioenamines and 2-Iminothiazolines.

A novel iodine/oxone-mediated three-component coupling reaction of 2-mercaptobenzoxazoles, amines, and ketones is reported. This transformation proceeds through the intermediacy of highly reactive sulfenamides, which serve a dual role as electrophilic sulfenylating agents and internal amine donors, enabling the efficient synthesis of valuable α-thioenamines and 2-iminothiazoline scaffolds. Using inexpensive, readily accessible, and environmentally benign reagents, this strategy offers a practical and sustainable approach to access highly functionalized 2-iminothiazolines with a broad substrate scope, excellent functional group tolerance, and operational simplicity.