Treatment of trans-[PtCl4(RCN)2] (R = Me, Et) with the hydrazone oximes
MeC(=NOH)C(R’)=NNH2 (R’ = Me, Ph) at 45 °C in CH2Cl2 led to the formation of
trans-[PtCl4{NH=C(R)ON=C(Me)C(R’)=NNH2}2] (R/R’ = Me/Ph, Et/Me, Et/Ph 1)

due to the regioselective OH-addition of the bifunctional MeC(=NOH)C(R’)=NNH2
to the nitrile group. The reaction of 1 and Ph3P=CHCO2Me allows the formation
of the Pt(II) complex trans-[PtCl2{NH=C(Et)ON=C(Me)C(Ph)=NNH2}2] (2). The
Schiff condensation of the free NH2 groups of 2 with aromatic aldehydes, i.e.
2-OH-5-NO2-benzaldehyde and 4-nitrobenzaldehyde brings about the formation
of the platinum(II) complexes trans-[PtCl2{NH=C(Et)ON=C(Me)C(Ph)=NN=CH(
C6H3-2-OH-5-NO2}2] (3) and trans-[PtCl2{NH=C(Et)ON=C(Me)C(Ph)=NN=CH(C
6H4-4-NO2}2], respectively, containing functionalized remote peripherical groups.
Metallization of 3 (fig), which can be considered as a novel type of metallaligand,
was achieved by its reaction with M(OAc)2·nH2O (M = Cu, n = 2; M = Co, n = 4)
in 1:1 molar ratio furnishing solid heteronuclear compounds with composition
[Pt]:[M] = 1:1. The complexes were characterized by C, H, N elemental analyses,
FAB+ mass-spectrometry, IR, 1H, 13C{1H} and 195Pt NMR spectroscopies, X-ray
structures were determined for 1, 2 and 3.