Carbido ligands

Fig. 16. Structures of the clusters (Cu2Ru6C(CO) 16(NCMe)2] and [Cu2Ru6(CO),8-(C6H5Me)2], with the CO ligands omitted for clarity, showing the change in skeletal geometry when an interstitial carbido ligand is formally replaced by two CO groups. [Reprinted with permission of Freund Publishing House Ltd. (11).]...

MoFe-Protein contains a second cluster, the M-cluster. [33] This is covalently bonded to cysteine and histidine of the a-suhunit. A homocitrate anion R)-2-Hydroxyhutane-l,2,4-tricarhoxylic acid) is complexed as a bidentate ligand with molybdenum (Fig. 4.5). On the basis of better resolved X-ray structural analysis and quantum mechanical calculations, initially it was thought, a nitrogen atom is located in the centre of the Fe/Mo complex, [34] but more recent results gave evidence for an interstitial carbido ligand [35,36], which is unprecedent in bioinorganic chemistry. 

The alkylisothiocyanates RN=C=S (R = Et, Bu", Cy) react with the alkylidyne WCl3(sCBu )(dme) to form insoluble polymeric products. Partially hydrolysed tetrameric units are identifiable through X-ray crystallography. X-ray crystallography shows that the carbido ligands of (Bu 0)3WsC-CsW(0Bu )3 are linear and that the central C-C bond is 1.38 A long, close to the... 

The chemistry of metal cluster carbonyls containing carbido ligands dates back to the discovery and characterization of the first example, Fc5C(CO)i5, in 1962. For the metal ruthenium, many examples of clusters with different nuclearity are... 

---