Novel Z-Selective Head-to-Head Dimerization of Terminal Alkynes Catalyzed by Lanthanide Half-Metallocene Complexes.

Reports on a novel organolanthanide catalyst system for the regio- and stereoselective head-to-head (Z)-dimerization of terminal alkynes. Recovery and reuse of the catalyst system; Reactivity of a series of half-metallocene alkyl complexes; High head-to-head (Z)-selectivity for the dimerization of of phenylacetylene by the lutetium anilido complexes.