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

Abstract

Deprotonation of the thioamidate group of [OsH{κ 2 -N,S-[NHC(CH 3 )S]}(�CPh)(IPr)(P i Pr 3 )]OTf [1; IPr = 1,3bis(2,6-diisopropylphenyl)imidazolylidene; OTf = CF 3 SO 3 ] results in the release of acetonitrile and formation of the terminal sulfide complex OsH(S)(�CPh)(IPr)(P i Pr 3 ) (2), which has been transformed into the hydrosulfide [OsH(SH)(�CPh)(IPr)(P i Pr 3 )]OTf (3) and the methylsulfide [OsH(SMe)(�CPh)(IPr)(P i Pr 3 )]OTf (4) through protonation and methylation reactions, respectively. The structure, spectroscopic characteristics, and reactivity of these compounds are compared. Reactions of 3 and 4 with 2hydroxypyridine and 2-mercaptopyridine afford [OsH{κ 2 -X,N-[X-py]}(�CPh)(IPr)(P i Pr 3 )]OTf [X = O (5), S( 6)].