NMR studies of transformations of Pt(II) and Pd(II) complexes with amino acids in solution. 1. Glycine complexes

Abstract

1H,13C, and195Pt NMR studies were performed for Pt(ll) and Pd(II) complexes with glycine cis- and trans-M(Gly)2, trans-Pd(GlyH)2Cl2 , cis- and trans-Pt(GlyH)2Cl2 , Na[Pd(GIy)Cl2], and K[Pt(Gly)CI2] in donor type solvents DMSO and H2O. It is shown that a cis ↔ trans equilibrium takes place in these solvents and that the equilibration rate is low for Pt(II) complexes and high for Pd(II) complexes. Therefore, the cis- and trans-complexes of Pt(II) may be recorded by NMR spectroscopy in the individual state, whereas for Pd(II) there is an equilibrium mixture of cis- and trans-isomers. Solvolysis of Cl-containing complexes in DMSO is studied. A mechanism of solvolysis involving eis ↔ trans isomerization of the dichloro complexes of Pd(II) is suggested. NMR spectral data for some solvolysis products are given.