Indenyl complexes of ruthenium(II). Crystal structure of [Ru(CO)(PPh3)2(η5-C9H7)]ClO4·CH2Cl2

The compound [RuCl(PPh3)2(η5-C9H7)] (I) has been made in high yield by reaction of [RuCl2(PPh3)3] with indene and potassium hydroxide in ethanol and its reactions have been examined. Complex I reacts with appropriate nucleophiles to give the complexes [RuX(PPh3)2(η5-C9H7)] (X = H, CH3, I, SnCl3, C2Ph) and [RuCl(dppe)(η5-C9H7)]. Heating of complex I with methanol in a sealed tube leads to the elimination of the indenyl group and decarbonylation of methanol. Cationic complexes of formulae [RuL(PPh3)2(η5-C9H7)]ClO4 (L = CH3CN, 2-ClC6H4CN, CH2CHCN, 1,2-(CN)2C6H4, C2H4(CN)2, N2H4, CNBut, CO, CCHPh, and C2H4) and [Ru(L-L)PPh3(η5-C9H7)]ClO4 (L-L = 2,5-norbornadiene (nbd), tetrafluorobenzobarrelene (tfb), ethylenediamine (en), propylenediamine (pn), biimidazole (Hbim), 2,2′-bipyridine (bipy) and 1,10-phenanthroline (phen)) are obtained by treatment of complex I with the appropriate ligand and sodium perchlorate in methanol. Reaction of the vinylideneruthenium complex [Ru(η1-CCHPh) (PPh3)2(η5-C9H7)]ClO4 with oxygen gives [Ru(CO)(PPh3)2(η5-C9H7)]ClO4. The structure of [Ru(CO)(PPh3)2(η5-C9H7)]ClO4·12CH2Cl2 has been determined by X-ray diffraction. The space group is P1 with lattice constants a 18.5513(14), b 12.9165(5), and c 9.6898(5) Å, and α 80.942(5), β 104.998(7) and γ 111.130(4)°. Final R and Rw factors are 0.039 and 0.043, respectively, for the 6836 observed data (3σ(I) criterion). The metal is bonded to an indenyl group through the five-membered ring, and hexacoordination of the ruthenium atom is completed by two triphenylphosphine ligands and a carbonyl group.