Triosmium complexes with alkyne ligands

The reactions of H20s3(GO)io and Os3(GO)io(MeGN)2 with l,4-dipyridylbuta-l,3-diyne afford a variety of products, ranging from triosmium complexes with a parallel alkyne to clusters with the ligand rearranged to form a... 

In contrast, when thiophenes react with triosmium carbonyl clusters it is C-H bond activation that occurs in preference to C-S bond cleavage. The direct reaction of [Os3(CO)i2], or the -acetonitrile complex [Os3(CO)io(NCMe)2], with thio-phene results in the oxidative addition of a C-H bond to give the exo- and endo isomers of the n, -thienyl hydrido cluster [Os3(//-H)(/z-C4H3S)(CO)io] (21a, 22a) (Scheme 7). These isomers are in rapid equilibrium at room temperature. The complex [Os3(/i-H)2(/X3-C4H2S)(CO)9] (23a) also results from his reaction, presumably by additional thermal C-H bond activation and decarbonylation of the thienyl complex. This cluster contains a triply bridging cyclic alkyne ligand related to /i3-benzyne. " ... 

Triruthenium and triosmium complexes obtained from functionalized alkynes Complexes containing ligands with methoxycarbonyl (or acetato) groups Complexes obtained upon CO insertion into M-C bonds Hydration-dehydration reactions of alkynols promofed by silica or alumina Osmium derivafives obfained from oxygenafed ligands... 

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