IRIDIUM(III)-PROMOTED AND RHODIUM(III)-PROMOTED BIONUCLEAR C-H BOND ACTIVATION OF PI-COMPLEXED PLATINUM(0) ETHYLENE AND PHENYLACETYLENE AND FORMATION OF HETEROBIMETALLIC COMPLEXES - X-RAY CRYSTAL-STRUCTURES OF [(ETA(5)-C(5)ME(5))(PME(3))IR(MU-H)(MU-ETA(2)ETA(1)-CH2==CH)PT(PPH(3))(2)](2+)-[(OSO2CF3)-O--](2) AND [(ETA(5)-C(5)ME(5))(PME(3))RH(MU-H)(MU-ETA(2)ETA(1)-PHC-C)PT(PPH(3))(2)](2+)-[(OSO2CF3)-O--](2)

Reactions of [(eta(5)-C(5)Me(5))(PMe(3))Ir(OSO2CF3)(2)], 1, and [(eta(5)-C(5)Me(5))(PMe(3))Rh(OSO2CF3)2], 2, with [(PPh(3))(2)Pt(pi-CH2=CH2)], 3, and [(PPh(3))(2)Pt(pi-HC=CPh)], 4, affords the complexes [(eta(5)-C(5)Me(5))(PMe(3))M(mu-H)(mu-eta(2):eta(1)-CH2=CH)Pt(PPh(3))(2)](2+)[(OSO2CF3)-O--](2) (M: Ir, 5; Rh, 6) and [(eta(5)-C(5)Me(5))(PMe(3))M(mu-H)(mu-eta(2):eta(1)-PhC=C)Pt(PPh(3) (2)](2+)[(OSO2CF3)-O--](2) (M: Ir, 7; Rh, 8). The formation of the Ir-Pt (5; 7) and Rh-Pt (6; 8) heterobimetallic complexes was promoted by C-H bond activation at ambient temperatures in CH2Cl2. These complexes have been fully characterized by NMR spectroscopy; particularly distinct are the upfield chemical shifts of the mu-hydride ligand between the two metallic centers. The structures of 5 and 8 have been determined by X-ray crystallographic analysis. Crystallographic data with Mo K alpha radiation (lambda = 0.70930 Angstrom): 5, PtIrC54H60P3S2O6F6Cl2, monoclinic, space group P2(1)/n, a = 14.053(2) Angstrom, b = 20.725(8) Angstrom, c = 20.509(5) Angstrom, beta = 103.80(1)degrees, Z = 4, R = 0.0419; 8, PtRhC59H60P3S2O6F(6), monoclinic, space group P2(1)/n, a = 14.455(4) Angstrom, b = 18.575(3) Angstrom; c = 22.626(4) Angstrom, beta = 104.54(2)degrees, Z = 4, R = 0.0337.