Mesomorphic dithiooxamide complexes of platinum(II)

Complexation of non-mesomorphic dithiooxamide ligands to Pt(II) leads to square planar complexes which exhibit mesomorphic properties. The synthesis of these complexes was accomplished in three steps: the formation of bisamides, starting from conveniently substituted anilines, their conversion into dithiooxamides and the reaction of these sulfur derivatives with [PtCl2(dmso)(2)]. Four, eight and twelve-chained complexes were obtained and their behaviour as potentially mesomorphic material was studied. The eight-chained complexes 21 (n = 12-16) and the twelve-chained complexes 22 (n = 8,11,13) exhibit columnar mesophases which have been characterised by optical microscopy, X-ray scattering and related miscibility studies.