The dimerization of terminal alkynes is one of the most useful and economical reactions to give conjugated enyne compounds, which are important for the synthesis of natural products. 1 However, only a limited number of highly selective syntheses of conjugated enynes by a dimerization have been reported 2 due to the competitive formation of undesired isomers (Scheme 1). In particular, the (E)-head-to-head dimerization is limited to aryl acetylene, 2a silyl ...
