Unequivocal Characterization of an Osmium Complex with a Terminal Sulfide Ligand and Its Transformation into Hydrosulfide and Methylsulfide.

Deprotonation of the thioamidate group of [OsH{κ-,-[NHC(CH)S]}(≡CPh)(IPr)(PPr)]OTf [; IPr = 1,3-bis(2,6-diisopropylphenyl)imidazolylidene; OTf = CFSO] results in the release of acetonitrile and formation of the terminal sulfide complex OsH(S)(≡CPh)(IPr)(PPr) (), which has been transformed into the hydrosulfide [OsH(SH)(≡CPh)(IPr)(PPr)]OTf () and the methylsulfide [OsH(SMe)(≡CPh)(IPr)(PPr)]OTf () through protonation and methylation reactions, respectively. The structure, spectroscopic characteristics, and reactivity of these compounds are compared. Reactions of and with 2-hydroxypyridine and 2-mercaptopyridine afford [OsH{κ-,-[X-py]}(≡CPh)(IPr)(PPr)]OTf [X = O (), S()].

Osmathiazole Ring: Extrapolation of an Aromatic Purely Organic System to Organometallic Chemistry.

An osmathiazole skeleton has been generated starting from the cation of the salt [OsH(OH)(≡CPh)(IPr)(PPr)]OTf (; IPr = 1,3-bis(2,6-diisopropylphenyl)imidazolylidene; OTf = CFSO) and thioacetamide; its aromaticity degree was compared with that of thiazole, and its aromatic reactivity was confirmed through a reaction with phenylacetylene. Salt reacts with the thioamide to initially afford the synthetic intermediate [OsH{κ--[NHC(CH)S]}(≡CPh)(IPr)(PPr)]OTf (). Thioamidate and alkylidyne ligands of couple in acetonitrile at 70 °C, forming a 1:1 mixture of the salts [OsH{κ--[C(Ph)NHC(CH)S]}(CHCN)(IPr)(PPr)]OTf () and [Os{κ--[CH(Ph)NHC(CH)S]}(CHCN)(IPr)]OTf ().

Dissimilarity in the Chemical Behavior of Osmaoxazolium Salts and Osmaoxazoles: Two Different Aromatic Metalladiheterocycles.

The preparation of aromatic hydride-osmaoxazolium and hydride-oxazole compounds is reported and their reactivity toward phenylacetylene investigated. Complex [OsH(OH)(≡CPh)(IPr)(PPr)]OTf (; IPr = 1,3-bis(2,6-diisopropylphenyl)imidazolylidene, OTf = CFSO) reacts with acetonitrile and benzonitrile to give [OsH{κ--[C(Ph)NHC(R)O]}(NCR)(IPr)(PPr)]OTf (R = Me (), Ph ()) via amidate intermediates, which are generated by addition of the hydroxide ligand to the nitrile. In agreement with this, the addition of 2-phenylacetamide to acetonitrile solutions of gives [OsH{κ--[C(Ph)NHC(CHPh)O]}(NCCH)(IPr)(PPr)]OTf ().