STRUCTURE OF CIS-DICARBONYL[2-CARBOXYLATO-1-METHOXYCARBONYL-2-(4-METHYL-PHENYL)VINYL]-TRANS-BIS(DIMETHYLPHENYLPHOSPHINE)RUTHENIUM(II), A COMPLEX CONTAINING A BIDENTATE VINYL LIGAND

[Ru(CO)2{C(CO2Me)=C(COO)(C6H4-Me)}(PMe2Ph)2]; [Ru(C12H10O4)(C8H11P)2(CO)2], M(r) = 651.6, orthorhombic, P2(1)2(1)2(1), a = 9.3667 (8), b = 13.6888 (20), c = 23.0421 (20) angstrom, V = 2954.4 angstrom3, Z = 4, D(x) = 1.465 Mg m-3, lambda(Cu K-alpha) = 1. 54184 angstrom, mu = 5.74 mm-1, F(000) = 1336, T = 298 K, R = 0.040 for 4794 observed reflections with F(o) > 3-sigma(F(o)) and 372 parameters. The complex exists as discrete monomeric units in the crystal, and exhibits approximate octahedral geometry around the Ru atom. The five-membered metallacycle ring is essentially planar with Ru-C and Ru-O distances of 2.087 (5) and 2.071 (4) angstrom. The Ru-C(carbonyl) distances of 1.824 (6) and 1.913 (6) angstrom show a marked difference. The average Ru-P distance is 2.384 (2) angstrom.