Preparation, structure and some chemistry of FcCtriple bond; length of mdashCCtriple bond; length of mdashCCtriple bond; length of mdashCRu(dppe)Cp

The synthesis of Fc(Ctriple bond; length of mdashC)3Ru(dppe)Cp (2) from Fc(Ctriple bond; length of mdashC)3SiMe3 and RuCl(dppe)Cp is described, together with its reactions with tcne to give the tetracyano-dienyl FcCtriple bond; length of mdashCCtriple bond; length of mdashC{C[double bond; length as m-dashC(CN)2]}2Ru(dppe)Cp (3) and -cyclobutenyl FcCtriple bond; length of mdashCCtriple bond; length of mdashC{Cdouble bond; length as m-dashCC(CN)2C(CN)2}Ru(dppe)Cp (4), with Co2(μ-dppm)n(CO)8−2n (n = 0, 1) to give FcC2{Co2(CO)6}C2{Co2(CO)6}Ctriple bond; length of mdashCRu(dppe)Cp (5) and FcCtriple bond; length of mdashCCtriple bond; length of mdashCC2{Co2(μ-dppm)(CO)4}Ru(dppe)Cp (6), respectively, and with Os3(CO)10(NCMe)2 to give Os3{μ3-C2Ctriple bond; length of mdashCCtriple bond; length of mdashC[Ru(dppe)Cp]}(CO)10 (7). On standing in solution, the latter isomerises to the cyclo-metallated derivative Os3(μ-H){μ3-C[Ru(dppe)Cp]CCC[(η-C5H3)FeCp]}(CO)8 (8). X-ray structural determinations of 1, 2, 6 and 7 are reported.