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.