Triosmium carbonyl complexes containing bridging ligands derived from ortho-functionalized anilines

Abstract

The trinuclear carbonyl clusters [Os 3)( μ-H( μ, η 2- o-HNC 6H 2Me 2NH 2)(CO) 9] (1) ( o-H 2NC 6H 2Me 2NH 2 = 1,2-diamino-4,5-dimethylbenzene), [Os 3( μ-H)( μ, η 2- o-OC 6H 4NH 2)(CO) 9] (2) ( o-HOC 6H 4NH 2 = 2-aminophenol) and [Os 3( μ-H)( μ, η 1- o-SC 6H 4NH 2)(CO) 10] (3) ( o-HSC 6H 4NH 2 = 2-aminothiophenol) have been prepared by reacting [Os 3(CO) 10(MeCN) 2] with the appropriate ortho-functionalized aniline in THF solvent. Compounds 1 and 2 are isostructural, having an Os-Os edge spanned by a hydride ligand and by the amido (1) or alkoxy (2) fragment of the monodeprotonated 1,2-diamino-4,5-dimethylbenzene or 2-aminophenol ligands. In both complexes, one of the metal atoms of the bridged Os-Os edge is also attached to the NH 2 group of the organic ligand. The structure of complex 3 is related to those of 1 or 2, in that an Os-Os edge is spanned by a three-electron donor ligand (the thiolate fragment of monodeprotonated 2-aminothiophenol), but differs in that the NH 2 group is uncoordinated. The X-ray structure of compound 3 is also reported. The results are discussed taking into account the hard-soft character of the bridging ligands.