Ternary complexes of palladium(II) containing (Te,S) and (Te,N) hybrid organotellurium ligands: synthesis, spectra and cis-transisomeric conversion

Abstract

Five ternary complexes of palladium(II) namely [Pd(L1)2](C104)2 (1), [Pd(LIXL2)](C104)2 (2), [(PPh3)2Pd(LI)](C104)2 (3), [(DPPE)Pd(L2)](C104)2 (4) and [Pd(L1XL3)](C104)2 (5) where L 1 = MeSCH2CH2TeAr , L 2 = Me2NCH2CHzTeAr (At = 4-MeOC6H 4) and L 3 = MeSCH2CH(OH)CHzSMe were synthesized by treating [PdC12l1 (El)] or [(PPh3)z/(DPPE)PdCI2)] with AgC10 4 and the appropriate ligand. The ligands L a, L z and L 3 in these complexes are judged to be coordinated in bidentate mode on the basis of 1H NMR and IR spectral data. All the complexes behave as 1 : 2 electrolytes in CH3CN. The 125Te{1H} NMR spectra of 1 and 2 indicate that the ligands L 1 and L z in them are in a cis disposition in freshly prepared dimethylsulphoxide-d6-CD3CN solutions, implying a similar configuration in the solid state but within a few hours there is partial conversion into the trans isomer.