A Dimorphic Os(IV) Complex with Pyramidal Sulfur Inversion in a Sulfanyl Chelating Ligand

Abstract

Coordination compound [Os(SC6F4H-4)2(SC6F3H-4(SC6F4H)-2)(C6H5)] is obtained during the thermolysis of [Os(SC6F4H-4)4(PPh3)] in non-dried toluene, as a product of C–F bond cleavage. The complex presents the expected trigonal–bipyramidal coordination geometry, with a thiolate-sulfanyl κ2 S,S’-ligand chelating the metal center in axial and equatorial sites. The complex was crystallized in the centrosymmetric space group C2/c and in the non-centrosymmetric space group Pna21. In both forms, the crystal is a RS racemate, with the chiral center being the axially coordinated sulfanyl S atom. In the case of the non centrosymmetric space group, the asymmetric unit retained for the refinement consists of two independent molecules related by a pyramidal sulfur inversion at the stereogenic center. Cell parameters: form I, C2/c, a = 20.8459(14) A, b = 12.2646(12) A, c = 25.253(3) A, β = 91.582(7)°; form II, Pna21, a = 16.208(2) A, b = 16.500(3) A, c = 23.604(3) A. An Os(IV) coordination complex bearing a thiolate-sulfanyl κ2 S,S’-ligand was crystallized in two spaces groups, C2/c with one molecule in the asymmetric unit, and Pna21 with two enantiomeric molecules in the asymmetric unit.