Copper Nitrate Mediated Regio- and Stereoselective Difunctionalization of Alkynes: A Direct Approach to α‑Chloro-β-nitroolefins

An efficient copper nitrate mediated chloronitration reaction was developed for the direct synthesis of α-chloro-β-nitroolefins with high regio- and stereoselectivity from simple alkynes and low toxic stannous chloride. This protocol provides a direct access to polysubstituted alkenes with operational simplicity, good functional group tolerance, and a wide substrate scope. Various applications of given products allowed the straightforward assembly of molecular complexity and indicated them as promising and valuable building blocks in organic synthesis.