Iodine-Promoted Thioylation and Dicarbonylation of Enaminone α‑C Sites: Synthesis of Fully Substituted Thiazoles via CC Bond Cleavage

A novel iodine-promoted difunctionalization of α-C sites in enaminones was demonstrated as a means of synthesizing a variety of fully substituted thiazoles by constructing C–C­(CO), C–S, and C–N bonds. This transformation allows the realization of enaminones as unusual aryl C2 synthons and simultaneously allows the thioylation and dicarbonylation of α-C sites. A preliminary mechanistic study was performed and indicated that the cleavage of CC bonds in enaminones involves a bicyclization/ring-opening and oxidative coupling sequence.