SESMic: A Reagent for the Synthesis of 5-Membered Heteroaryl Masked Sulfinates.

Sulfur(VI) functionalities are found in numerous value-added products; however, methods for the synthesis of heterocyclic sulfonyl fluorides are limited. 4-Substituted sulfonyl fluoride azoles could be useful synthons in drug discovery and biochemical applications due to their enhanced stability derived from their electron-rich nature. In this study, we develop an isocyanide reagent, SESMic, that contains a sulfinate protecting group allowing for synthesis of a variety of heterocycles followed by sulfinate unmasking and further functionalization. SESMic specifically allows access to 4-substituted sulfonyl fluorides, which were shown to be more stable than their aryl congeners.