Dithiocyanation of Alkynes with N-Thiocyanato-dibenzenesulfonimide and Ammonium Thiocyanate

Organic thiocyanates widely exist in natural products, and act as important precursors for organic synthesis. An efficient dithiocyanation of alkynes with N-thiocyanato-dibenzenesulfonimide (NTSI) as the SCN⁺ cation and ammonium thiocyanate as the SCN^- anion sources has been developed. Highly active electrophilic reagent NTSI could react with various types of alkynes to build C(sp²)−SCN bond to provide a variety of dithiocyanato olefin compounds under simple and mild conditions. Trace amount of water is beneficial to the dissociation of ammonium thiocyanate, which makes the SCN^- anion easier to participate in the reaction. The protocol owns a broad substrates scope including terminal and internal, alkyl and aryl alkynes, excellent functional group tolerance and good regioselectivity.