Synthetic and spectroscopic aspects of tetraazamacrocyclic complexes of palladium(II)

Palladium(LI) complexes of the general composition [PdMacL]Cl-2 (MacL = mac rocyclic ligand) containing 14-18 membered rings have been synthesized by t he template condensation of the aliphatic diamines H2N(CH2)(n)NH2 (n = 2 or 3) with the dicarboxylic acids HOOC-(CH2)(m)-COOH (m = 1 or 2) in methanol . A square-planar environment of the ligand around the metal ion has been s uggested on the basis of chemical analyses, infrared and H-1 NMR spectral s tudies, electronic spectra, molecular weight determinations and conductivit y measurements. Spectroscopic studies confirm coordination of amide nitroge ns to the central metal ion. The molar conductance values of the palladium( II) complexes show that they are 1:2 electrolytes.