The reaction of [Os3(CO)10(MeCN)2], with heterocyclic thioamides. The crystal and molecular structure of [Os3(µ-H)(CO)10(µ-SCNCH2CH2S)]

Abstract

The reaction of [Os₃(CO)₁₀(MeCN)₂] with the heterocyclic thioamides HL yields products which are formulated as [Os₃H(CO)₁₀L](L being the deprotonated thioamide co-ordinated via the exocyclic sulphur atom). The structure of [Os₃H (CO)₁₀(S[graphic omitted])] has been established by an X-ray analysis. The crystals are monoclinic, space group P2₁/c, a= 19.387(8), b= 9.528(2), c= 24.420(7)Å, = 111.20(2)°, and Z= 8. The structure was refined to R= 0.0825 for 5 390 unique diffractometer data. The osmium atoms define a triangle with the thioamide ligand bridging one edge via the exocyclic sulphur atom. Spectroscopic data on the complexes, supported by the X-ray structure of [Os3H (CO)10(S[graphic omitted])], indicate the thioamide ligands are binding in the thiolate form. The [Os₃H (CO)₁₀L] complexes are decarbonylated to yield [Os₃H (CO)₉L] complexes upon reaction with trimethylamine oxide or by refluxing in octane. Further thermolysis of [Os₃H(CO)₉(S[graphic omitted])] affords the sulphur capped species [Os₃H(CO)₉(µ₃-S)L](L = thiazolinyl ligand formed from the desulphurization of (S[graphic omitted]).