An Efficient and General Microwave‐Assisted Copper‐Catalyzed Conia‐Ene Reaction of Terminal and Internal Alkynes Tethered to a Wide Variety of Carbonucleophiles

This paper describes a highly efficient, microwave‐assisted, Conia‐ene reaction of alkynes bearing a stabilizing carbon nucleophile. The reaction, catalyzed by a commercially available copper catalyst, proceeds under neutral conditions and is generally applicable even to less reactive nucleophiles such as malonate, cyanoacetate, and sulfonylacetate derivatives. This copper‐mediated cycloisomerization is also applicable to internal unactivated alkynes leading exclusively to the corresponding 5‐membererd products having an E‐olefinic chemistry.