PREPARATION AND CHARACTERIZATION OF (AMINO CARBOXAMIDATO-N,N') (CHLORO)(DIMETHYL SULFOXIDE-S)-PLATINUM(II) COMPLEXES

Several square-planar complexes of the [PtCl(aaa-N,N')(dmso-S)] type w ere prepared (aaa=amino acid amidate, dmso=dimethyl sulfoxide). The cr ystal and molecular structures for cis(NH2,S)-[PtCl(DL-alaa)(dmso)]. H 2O (4) and trans(NH2,S)-[PtCl(DL-vala)(dmso)] (3b) were determined by X-ray diffraction (alaa=alaninamidate, vala=valinamidate). The crystal of 4 was triclinic, space group <P(1)over bar> with a= 9.144(2), b=9. 172(3), c=7.371(2) Angstrom, alpha=109.41(2)degrees, beta=99.69(2)degr ees, gamma=76.13(3)degrees, Z=2, and final R=0.029 and R(w)=0.034. The crystal of 3b was monoclinic, space group P2(1) with a=7.158(2), b=9. 948(2), c=8.741(2) Angstrom, beta=102.76(2)degrees, Z=2, and final R=0 .041 and R(w)=0.050. Both complexes were found to contain a carboxamid ato group coordinating to platinum(II) through the nitrogen atom. A la rger trans influence was observed for the coordinating carboxamidato n itrogen atom than for the amino one. The prepared complexes were chara cterized by NMR, visible and UV, and CD spectra in comparison with the complexes of [PtCl(aa-N,O)(dmso-S)] type (aa=amino acidate).