Synthesis and structure of dithizonato complexes of antimony(III), copper(II) and tin(IV)

Abstract

In view of the important role of dithizone in trace metal analyses, new structural aspects and approaches used to probe metal complexes of dithizone are of interest. Three X-ray diffraction structures are reported, dichloro-bis(dithizonato)tin(IV), dichloro-(dithizonato)antimony(III) and bis(dithizonato)copper(II). During synthesis of the tin complex, autooxidationof SnIICl2 to SnIV occurred without chloride liberation. The SbIII complex revealed a unique distorted seesaw geometry which is, as for the other complexes, conveniently explained by DFT calculated molecular orbital orientations. Computed lowest reaction energies are in agreement with experimentally obtained reaction products, which, together with molecular orbital renderings serve as a suitable tool towards the prediction of modes of coordination in these complexes. The S-M-N bond angle in the 5-membered coordination ring shows a linear relationship with the corresponding metal ionic radii.