We have successfully synthesized the zinc and cadmium complexes containing bis(3-trimethylsilyl-2-thiophenyl)phenylphosphine (SiPS2): [NEt4][(SiPS2)Cd(SC6H5)] (1) , [NEt4][(SiPS2)Cd(SC6H11)] (2) , [NEt4][(SiPS2)Cd(SCH2C6H5)] (3) , [NEt4][(SiPS2)Zn(SC6H5)] (4) , [NEt4][(SiPS2)Zn(SC6H11)] (5) and [NEt4][(SiPS2)Zn(SCH2C6H5)] (6) , and characterized them using 31P NMR and mass spectrum.1 and 2 were also characterized by X-ray diffraction methods. In the attemprs to get crystals of 4 and 6, we got the oxidized dimer complex 4* and 6* instead. In these complexes the two oxygen atoms of the oxidized ligands and the sulfur atom of the monodentate thiolate ligand bridge both the cadmium centers. Zinc complexes exhibit distorted tetrahedral structure. However, the cadmium ion tends to form five coordination oxidation dimeric complexes.

The polydentate ligands containing both thiolato and phosphino groups have been used in catalysis and enzyme mimetic studies. We have synthesized two tetradentate thiophosphine ligands : tris(2-thiophenyl)- phosphine¡]H3L1¡^ and tris(3-trimethylsilyl-2-thiophenyl)phosphine (H3L3) and one tridentate thiophosphine ligand (bis(2-thiophenyl)- phenylphosphine¡]H2L2¡^. These ligands formed a series of germanium and tin metal complexes. We are thus exploring a range of syntheses of tin and germanium complexes. The ligand H3L1 react with SnCl4 to give trimeric tin units with bridging methoxyl group and oxo group. The ligand H2L2 react with SnCl4 or GeCl4 to give ML2 type complexes. H3L3 with germanium and tin metal complexes were synthesized and characterised by NMR spectra and mass spectra. We also obtained crystal structure of complexes GeCl(L3) and GeEt(L3). The structure was trigonal bipyramidal.