BINUCLEAR TRANSITION-METAL COMPLEXES OF SCHIFF-BASE MACROCYCLES CONTAINING THE FURANYL MOIETY

Binucleating macrocycles L comprised of two molecules of 2,5-diformylfuran and two molecules of 1,3-diaminopropane have been synthesized as cobalt(II), nickel(II) and copper(II) complexes by template reactions. On the basis of various spectroscopic studies the 20-membered macrocyclic complexes can be described as having six-coordinate octahedral structures where L is bonding through the nitrogens of 1,3-diaminopropane and the oxygens of the furanyl moiety. The elemental analyses and molecular ion peak from the mass spectra confirm their proposed 2:1 metal ligand stoichiometry. The overall geometries have been proposed on the basis of elemental analysis, i.r., H-1 nmr, mass, reflectance spectra and magnetic susceptibility measurements.