Cyclopentadienyl-ruthenium and -osmium chemistry. Part 15. Some cyanocarbon and cyanonitrogen complexes: crystal and molecular structures of [Ru{NCC(CN)C(CN)C(CN)2}{P(OMe)3}(PPh3)(η-C5H5)]

Abstract

A series of cyanocarbon and cyanonitrogen derivatives [RuR(PPh₃)₂(η-C₅H₅)]{R = CH(CN)₂, C(CN)₃, N(CN)₂, C₃(CN)₅, and N[C₂(CN)₃]₂} have been prepared from reactions between [RuCl(PPh₃)₂(η-C₅H₅)] and the appropriate cyano-substituted anion. The R groups are probably attached via Ru–N bonds, i.e. they are keteniminato-complexes; this was confirmed for R = C₃(CN)₅ by an X-ray diffraction study of the complex [Ru{NCC(CN)C(CN)C(CN)₂}{P(OMe)₃}(PPh₃)(η-C₅H₅)]. Crystals are monoclinic, space group C2/c, a= 18.845(8), b= 20.967(6), c= 19.336(7)Å, β= 118.54(3)°, and Z= 8, the structure being refined to a residual of 0.042 for 3 646 ‘observed’ reflections. The ruthenium atom is pseudo-octahedrally co-ordinated by the cyclopentadienyl ring [Ru–C 2.160(12)–2.236(6)Å], the two phosphine ligands [Ru–PPh₃ 2.322(2), Ru–P (OMe)₃ 2.239(2)Å], and the ligand nitrogen atom [Ru–N 2.033(6)Å].