The reactivity of palladacycle dimeric complexes with substituted triarylphosphito ligands P(OR)(3) (R = Ph, m-MeC6H4, o-MeC6H4, C6H3-2,4-tBu(2)) as well as their non-orthometallated analogues PdCl2[P(OR)(3)](2) was tested in a copper-free Sonogashira reaction with iodobenzene and phenylacetylene as substrates and imidazolium ionic liquids as the reaction medium. The ionic liquids [bmim][PF6], [bmim][BF4] and [emim][SO4Et] were chosen. The palladium complexes studied showed high activity, and the yield of diphenylacetylene ranged from 31 to 98% in 1 h. The best results were obtained in [bmim][PF6] for PdCl2[P(O-m-MeC6H4)(3)](2) (84%) and for orthopalladated dimer with the same phosphite (98%).