SYNTHESIS AND CHEMISTRY OF HETEROBIMETALLIC FULVALENE COMPLEXES CONTAINING W, MO, AND RH

The photo- and thermal chemistry of the heterobimetallic fulvalene (Fv ) complex Fv[W(CO)3Me][Rh(CO)2] (1) was investigated, and compounds Fv (CO)2MeWRh(CO)[mu-CO] (2), Fv(CO)3WRh(CO)Me (3), and Fv(CO)3WRh(CO)C(O )Me (4) were characterized. Reaction mechanisms were studied by labeli ng experiments using (CO)-C-13 and by analogy to the Mo-Rh system. The complexes Fv(CO)3MoRh(CO)C(O)Me (7) and Fv(CO)3MoRh(CO)Me (8) were ch aracterized. Reaction of 3 and 4 with PMe3 gave the zwitterionic speci es Fv[W(CO)3][Rh(PMe3)2Me] (16) and Fv[W(CO)3][Rh(PMe3)2C(O)Me] (17), respectively. An excess of PMe3 led to the mononuclear compounds FvRh( PMe3)2Me (18) and FvRh(PMe3)2C(O)Me (19). The latter was reacted with Mo(CO)3(EtCN)3 to give zwitterionic Fv[Mo(CO)3][Rh(PMe3)2C(O)Me] (20). The X-ray structures of the acyl complexes 4 and 17 were obtained. X- ray data of 4: P1BAR, a = 13.529(3) angstrom, b = 15.813(3) angstrom, c = 16.164(3) angstrom alpha = 62.72(1)-degrees, beta = 87.24(1), gamm a = 86.32(1)-degrees, V = 3065.9(11) angstrom3, Z = 8, R(w) = 0.045. X -ray data of 17: P2(1)/n, a = 15.412(4) angstrom, b = 9.745(2) angstro m, c = 18.209(6) angstrom, alpha = 90.0-degrees, beta = 93.46(2)-degre es, gamma = 90.0-degrees, V = 2730.0(22) angstrom3, Z = 4, R(w) = 0.03 03.