Carbonylcyanometalates as building blocks:: heterometallic complexes containing Mn(μ-C=N)M (M = Cu, Au, Ni, Pd or Pt), Mn(μ-C=;N)Pd(μ-dppm)2Mn and Mn(μ-C=N)M(μ-dppm)2Pd(μ-N=C)Mn (M = Pt or Pd) chains of atoms and crystal structure of the mixed-metal cluster [Ru3{(μ3-NC)MnCp(CO)2}(μ-AuPPh3)(CO)10]

A comparison between the products obtained by reaction of the isosteric metalates [MoCp(CO)(3)](-) (Cp=eta(5)-C5H5) and [MnCp(or Cp')(CN)(CO)(2)](-) (Cp'=eta(5)-C5H4Me) with various mono- or poly-nuclear complexes of Cu, Au, Ni, Pd, Pt or Ru showed that the metal-centered basicity of the former leads to metal-metal bonding whereas the dominant sigma-donor properties of the CN ligand in the latter preferentially lead to the formation of cyanide bridges between the metal centres. Only in the case of the unusual heterometallic octanuclear cluster [(OC)Pd(mu-NC)MnCp'(CO)(2)](4) were direct metal-metal bonding and CN-bridge formation observed. The crystal structure of [Ru-3{(mu(3)-NC)MnCp(CO)(2)}(mu-AuPPh3)(CO)(10)] was shown by X-ray diffraction to consist of a Ru3Au butterfly whose Ru-Ru hinge is bridged by the N-bonded NCMnCp(CO)(2) fragment. Controlled thermolysis of the octanuclear cluster [(OC)Pd(mu-NC)MnCp'(CO)(2)](4) led to the formation of bimetallic particles.