Vinylideneruthenium-Catalyzed Homo and Cross Dimerization of Acetylenes

Significance

Homo dimerization of terminal acetylenes was achieved by using a catalytic amount of vinylideneruthenium and N-methylpyrrolidine. Moderate to excellent yield can be obtained with aromatic acetylenes showing excellent regio- and geometrical selectivity. A mixture of an aromatic acetylene and a trialkylsilyl acetylene (large excess) under the same conditions resulted in a cross-dimerization product in good to excellent yield and excellent regio- and geometrical selectivity.