Some cyclic ligands obtained from reactions of polycyanocarbon–metal complexes

Several complexes containing Ru(dppe)Cp* fragments attached to heterocyclic ligands were obtained from polycyanocarbons. Reactions of Ru{Ctriple bond; length of mdashCC(CN)double bond; length as m-dashC(CN)2}(dppe)Cp* with LiCtriple bond; length of mdashCSiMe3 and LiOCHdouble bond; length as m-dashCH2 gave binuclear {[Ru(dppe)Cp*]Ctriple bond; length of mdashC–c-Cdouble bond; length as m-dashC(Ctriple bond; length of mdashCSiMe3)N(H⋯OH2)CCdouble bond; length as m-dashC(CN)}2(Ndouble bond; length as m-dashN) 2 and Ru{c-Cdouble bond; length as m-dashCHC[double bond; length as m-dashC(CN)2]CHdouble bond; length as m-dashCHO}(dppe)Cp* 4 [together with known Ru{Ctriple bond; length of mdashCCMedouble bond; length as m-dashC(CN)2}(dppe)Cp* 3], respectively, while lithiation of Ru(Ctriple bond; length of mdashCCtriple bond; length of mdashCH)(dppe)Cp* and subsequent reaction with TCNE afforded Ru{Ctriple bond; length of mdashC–c-Cdouble bond; length as m-dashC(CN)C(O)NH[double bond; length as m-dashC(CN)2]}(dppe)Cp* 6 and Ru{Ctriple bond; length of mdashC–c-Cdouble bond; length as m-dashCHC[double bond; length as m-dashC(CN)2]NHCMedouble bond; length as m-dashN}(dppe)Cp* 7, as well as known {Ru(dppe)Cp*}2{μ-Ctriple bond; length of mdashCC[double bond; length as m-dashC(CN)2]C[double bond; length as m-dashC(CN)2]Ctriple bond; length of mdashC} 5. A second product from the earlier described reaction between TCNE and Ru(Ctriple bond; length of mdashCCtriple bond; length of mdashCI)(dppe)Cp* was identified as Ru{Ctriple bond; length of mdashC–c-CC(CN)C(CN)double bond; length as m-dashC(NH2)C(CN)2}(dppe)Cp* 9. X-ray determined structures of 2, 4, 6, 7 and 9 are reported together with plausible routes by which they may be formed.