Nucleophile Addition von Carbonylmetallaten an kationische Alkin‐Komplexe [CpL 2 M(η 2 ‐RC≡CR)] + (M = Ru, Fe): μ‐η 1 :η 1 ‐Alkin‐verbrückte Komplexe

Hydrocarbon‐Bridged Complexes, XIIII). ‐ Nucleophilic Attack of Carbonylmetallates on Cationic Alkyne Complexes [CpL 2 M(η 2 ‐RC I CR)]+(M = Fe, Ru): μ‐η 1 : η 1 ‐Alkyne‐Bridged Complexes The σ,σ‐alkyne‐bridged complexes Cp(Me 3 P) 2 Ru[μ‐η 1 :η 1 ‐(MeO 2 C)C = C(CO 2 Me)]ML n ( 1 ) [ML n = Ru(CO) 2 Cp, Mn(CO) 5 , Re(CO) 5 ] are formed by addition of [Ru(Cp)(CO) 2 ] ‐ , [Mn‐(CO) 5 ] ‐ , and [Re(CO) 5 ] ‐ to the alkyne ligand of [Cp‐(Me 3 P) 2 Ru(MeO 2 CC≡CCO 2 Me)] + and by addition of [Re‐(CO) 5 ] ‐ to [Cp(OC)(Ph 3 P)Fe(MeC≡CMe)] + . The crystal structure of 1a was determined by X‐ray diffraction and allows the comparison of bimetallic complexes with M–C≡C–M, M–C(R)=C(R)–M, and M – CH 2 CH 2 –M bridges. Addition of [Re(CO) 5 ] ‐ to [Cp(OC)(L)Fe(RC≡CR)] + (L = CO:R = Me; L = P(OPh) 3 , PPh 3 ; R = Et) yields the complexes Cp(OC)‐(L)Fe‐Re(CO) 5 ( 3 ) with metal–metal bond.