COUPLING OF ALKYNYL LIGANDS AT A QUADRUPLY BONDED MOLYBDENUM DIMER

The complex 2(C=CSiMe(3))(3)(mu,eta(2):eta(2)-HC=CSiMe(3)){mu, (SiMe(3 ))-eta(2)-C=CSiMe(3)}(mu-dmpm)(2)][Li(dme)] ([1][Li(dme)]; dmpm = 1,2- bis(dimethylphosphino)methane, dme = 1,2-dimethoxyethane) was prepared in 32% yield from the reaction between Mo2Cl4(dmpm)(2), LiCCSiMe(3), and HCCSiMe(3) in dme. A single-crystal X-ray diffraction study of [1] [Li(dme)(0.5)-(OEt(2))(0.5)] revealed that 1 contains an alkynylvinyli dene ligand derived from the head-to-tail coupling of two alkynyl liga nds.