Abstract Enyne cross metathesis of terminal 1, 3-diynes with various alkenes afforded two products of distinctive connectivity, as the result of a uniform mode of initiation but different modes of termination events with or without metallotropic [1, 3]-shift. Steric and electronic factors of the substituents on the 1, 3-diynes play an important role in controlling the metallotropic [1, 3]-shift of the propagating alkylidene intermediates and their ...