The ketenylidene route to mixed-metal carbide clusters: -, -, 2-, 2-, -, 2- and -

Article abstract of DOI:10.1016/0022-328X(90)87229-7

Redox-condensation reactions between the ketenylidene clusters ^2- (M = Ru, Os) and electrophilic transition-metal reagents provide a convenient route to the new carbido clusters , -, 2, 2(Mo2Ru3C(CO)16>, , 2 and .These clusters have been characterized by elemental analysis, IR and variable-temperature 13C NMR spectroscopy, and, in the case of and 2 by single-crystal X-ray diffraction studies.The ^- cluster consists of a butterfly array of metal atoms with the manganese occupying a hinge position.The structure of the ^2- is a distorted (opened) octahedron of metal atoms, with the three rhutenium atoms forming one closed face of the octahedron, and the carbide ligand occupying an interstitial site. 13C NMR data indicate the octahedron closes in solution.For and , the carbide ligands show variable temperature NMR behavior, which is best interpreted in terms of a two-bond spin-spin coupling of the carbide to the two endo carbonyls on the wingtip Ru or Os atoms.A similar two-bond coupling process may possibly also be operating in the ^2- cluster.