CLUSTER CHEMISTRY .92. DIRECTED SYNTHESES AND CRYSTAL-STRUCTURES OF [(RU3(CO)11)(MU-PPH2[C2CO2(CO)6]C2)(RU2-(MU-PPH2)(CO)6)]CENTER-DOT-CH2CL2, [(OS3(CO)11)(MU-PPH2C2C2)(CO2OS3-(MU-PPH2)(CO)13)] AND [CO2OS3RE(MU-6-C2C=CH(PPH2))-(MU-PPH2)(MU-CO)2(CO)14]CENTER-DOT-CH2CL2

Reactions of (Co2(CO)8] with [{Mn(CO)11}2(mu-bdpp)] [M(n) = Ru3, Os3, Re3(mu-H)3, or Ru4(mu-H)4; bdpp = PPh2C2C2PPh2] afforded [{Mn(CO)11}2(mu-PPh2[C2Co2(CO)6]C2PPh2}] [M(n) = Ru3 1, Os3 2, Re3(mu-H)3 3 or Ru4(mu-H)4 4] in which the Co2(CO)6 moiety bonds to one of the C=C triple bonds of the bridging bdpp ligand. Pyrolysis of 1 yielded [{Ru3(CO)11}{mu-PPh2[C2Co2(CO)6]C2}{RU2(mu-PPh2)(CO)6}] 5, which is formed by concomitant addition of a P-C(sp) bond to one Ru3 cluster and elimination of a Ru(CO)4 fragment. In [{Os3(CO)11)(mu-PPh2C2C2){Co2Os3(mu-PPh2) (CO)13}] 8, obtained by heating 2, the Co2Os3 cluster consists of three edge-sharing triangles; the C2 fragment interacts with all five metal atoms. Reaction of the mixed-metal complex [{Os3(CO)11}(mu-bdpp){Re3(mu-H)3(CO)11)] 10 with [Co2(CO)8] yielded a 1:1 isomeric mixture of [{Os3(CO)11}{mu-PPh2[C2Co2(CO)6]C2PPh2}{Re3(mu-H)3(CO)11}] 11a and [{Re3(mu-H)3(CO)11)(mu-PPh2[C2Co2(CO)6]C2PPh2}{Os3(CO)11)] 11b. Pyrolysis of 11a afforded [Co2Os3Re{mu6-C2C=CH(PPh2)}(mu-PPh2)(mu-CO)2(CO)14] 12 in which all three transition metals form a cluster about the C4P fragment of the original bdpp ligand, which has also added one H atom to the carbon adjacent to the PPh2 group. The second PPh2 group bridges an Os-Os bond. Molecular structures of 5, 8 and 12 were determined by X-ray crystallography.