Recent Advances in Cu-Catalyzed Transformations of Internal Alkynes to Alkenes and Heterocycles

Numerous metal catalyzed reactions of internal alkynes towards synthetically and pharmacologically important alkenes and heterocycles appear in the literature. Among these the Cu catalyzed reactions have special place and has prompted the investigation and synthesis of carbon–carbon and carbon–heteroatom bond forming reactions. These reactions possess wide scope and during the path of these reactions either stable or in-situ intermediates are formed by the addition of Cu as a core catalyst or synergistic catalyst. In this review, we aim at compiling different contributions in Cu catalyzed reactions of internal alkynes towards the synthesis of different valuable alkenes and heterocycles which appear in the literature since last decade. We anticipate that this appraisal will deliver the basic insights for further advancement of Cu- catalyzed reactions in organic chemistry.