Activating Effect of AlCl3 in Homocoupling Reaction of Acetylene Derivatives under the Action of Mg–Cp2ZrCl2 Reagent Systems

The activating effect of AlCl₃ in the amount of 10 mol % in the homocoupling of alkyl-, phenyl-, and silyl-substituted acetylenes with the Mg–Cp₂ZrCl₂ reagent system was found for the first time. The unique nature of this activation is indicated by the fact that in the presence of 10 mol % of Lewis acids BF₃⋅Et₂O, Me₃SiCl, InCl₃, and SnCl₄, the reaction with 5-decyne does not occur even after 5 h, while in the presence of AlCl₃, homocoupling products are selectively formed in high yields within 10 min at room temperature.