PdCl2(P(OPh)3)2 catalyzed coupling and carbonylative coupling of phenylacetylenes with aryl iodides in organic solvents and in ionic liquids

Efficient cross-coupling and carbonylative coupling of terminal alkynes with aryl iodides catalyzed by PdCl2(P(OPh)(3))(2) in the presence of NEt3 in toluene and in ionic liquids is described. In imidazolium ionic liquids, [bmim]PF6 or [mokt]PF6 (bmim = 1-butyl-3-methyl imidazolium cation, mokt = 1-methyl-3-octyl imidazolium cation) catalyst was recycled and used in four concecutive catalytic cycles with high activity. In the absence of aryl iodide the same catalytic system catalyzed head-to-tail dimerization of phenylacetylene to the 1,3-diphenyl enyne, trans-PhC C-C(Ph)=CH2, with a yield of 85%.