Synthesis and characterization of the amidine complexes trans-[PtCl(NH3){HN=C(NH2R)}2 (R = Me, Ph, CH2Ph) derived from addition to the coordinated nitriles in trans-[PtCl2(N=CR)2]

The di-nitrile complexestrans-[PtCl2(N,,CR)2] (R = Me, Ph, CH2Ph) react with an excess of gaseous NH3 in CH2Cl2 at - 10C to form, in high yield, the corresponding di-amidine complexes trans-[PtCl(NH3){HN=C(NH2)R}2]Cl in which also one chlorine ligand has been displaced by NH3. The 1H NMR spectra in DMSO showed the formation of different species which were characterized through NOESY, TOCSY and 1H/13C heteronuclear correlations as trans-[Pt(NH3){HN=C(NH2)R}2(DMSO)]Cl2 and trans-[PtCl{HN=C(NH2)R}2(DMSO)]Cl