Electrochemical Sulfenamide Synthesis Bypassing Gaseous Amines with Formamide Surrogates

A novel, transition metal- and oxidant-free electrochemical method has been developed for the synthesis of sulfenamides with high atom economy (84.1%). This strategy employs commercially available N,N-dimethylformamide (DMF) and its derivatives as liquid, safe, and convenient surrogates for low-boiling amines, thereby overcoming the handling challenges associated with gaseous amines such as dimethylamine. Under constant current conditions, a variety of thiols and disulfides undergo efficient cross-coupling with formamides to afford the corresponding sulfenamides in good to excellent yields. The reaction features a broad substrate scope, excellent functional group tolerance, mild conditions (50 °C, air atmosphere), and simple workup without the need for column chromatography in many cases. Gram-scale synthesis and preliminary mechanistic studies are also presented, highlighting the practical utility and potential reaction pathway of this sustainable electrocatalytic protocol.