gem-Selective Cross-Dimerization and Cross-Trimerization of Alkynes with Silylacetylenes Promoted by a Rhodium-Pyridine-N-Heterocyclic Carbene Catalyst
The gem-selective cross-dimerization and -trimerization of silylacetylenes with alkynes through CH activation using a rhodium(I)-pyridine-N-heterocyclic carbene catalyst have been developed. This reaction is applied to various aliphatic or aromatic terminal alkynes, internal alkynes, and gem-1,3-disubsituted enynes to afford the corresponding enynes and dienynes with high regio- and stereoselectivities and in good isolated yields (up to 91%).