Metal-Catalyzed Cross-Coupling of Terminal Alkynes with Different Carbene Precursors

Metal carbene-involved C-H insertion reaction is among the most useful and efficient method for the construction of C-C bonds. While C(sp3)-H insertion and C(sp2)-H insertion have been intensively studied during the past several decades, C(sp)-H insertion of terminal alkynes with metal carbenes has only received great attention from the synthetic community recently. This cross-coupling reaction between terminal alkynes with different metal carbene precursors offers a versatile strategy for the synthesis of different types of alkynes or allenes, which are very useful synthetic intermediates in organic synthesis. This type of cross-coupling reaction, in which a migratory insertion step of alkynylsubstituted metal carbene species is generally involved, also offers new opportunities for the development of related cascade or multicomponent reactions.