Trivalent metal ion directed synthesis and characterization of macrocyclic complexes

A novel series of complexes of the type [M(TML)X]X2, where TML is a tetradentate macrocyclic ligand, M = Cr(III), Mn(III) or Fe(III), X = Cl-, CH3COO- or ? NO3, were synthesized by template condensation of dibenzoyl and thiocarbohydrazide in the presence of trivalent metal salts in a methanolic medium. The complexes were characterized with the help of elemental analyses, conductance measurements, molecular weight determination, magnetic measurements, electronic, NMR, infrared and far infrared spectral studies. The electronic spectra together with the magnetic moments suggest five coordinate square pyramidal geometry for these complexes. The molar conductance indicates them to be 1:2 electrolytes.