FORMATION OF [COPT2CL2(PPH(3))(4)(MU(3)-S)(2)] FROM FACILE HETEROMETALLATION OF [PT-2(PPH(3))(4)(MU-S)(2)] AND ITS FACILE DEHETEROMETALLATION VIA CARBONYLATIVE DESULFURIZATION TO GIVE PT-PT BONDED [PT-2(CO)(2)(PPH(3))(2)(MU-S)]

Metallation of [Pt-2(PPh(3))(4)(mu-S)(2)] 1 with CoCl2 gave [CoPt2Cl2( PPh(3))(4)(mu(3)-S)(2)] 2 at room temperature. Treatment of 2 with CO in an autoclave resulted in a binuclear compound [Pt-2(CO)(2)(PPh(3))( 2)(mu-S)] 3, via a reductive desulfurization mechanism with the remova l of the heterometal fragment and formation of a Pt-Pt bond. Complexes 2 and 3 have been characterized by single-crystal X-ray crystallograp hy. The structure of 2 shows a trigonal-bipyramidal arrangement of a { CoPt2S2} core with non-bonding Pt-Pt and Co-Pt distances at 3.197(4) a nd 3.066(1) Angstrom respectively. Complex 3 contains a {Pt2S} triangu lar core with two PPh(3) ligands trans and two CO cis to the Pt-Pt bon d [2.600(1) Angstrom]. Some theoretical aspects of the strength of the Pt-Pt bond in relation to the ligands on the {Pt2S} core are discusse d.