SYNTHESIS, CHARACTERIZATION, ELECTROCHEMISTRY AND AXIAL LIGATION PROPERTIES OF MACROCYCLIC DIVALENT METAL-COMPLEXES OF ACETYLACETONE BUCKLED WITH DIFFERENT DIAMINES

A series of macrocyclic nickel(II) copper(II) complexes using acetylac etone and different aliphatic and aromatic diamines (1,2-diamino ethan e, 1,2-diamino propane, 1,2-diamino benzene, 1,3-diamino benzene and 3 ,4-diamino toluene) has been synthesized by the template method. These complexes were characterized by elemental analysis, conductivity meas urements, electronic, infrared and NMR spectral data. The molar conduc tivity data show them to be non-electrolytes. The electronic spectral data in toluene (a non-coordinating solvent) suggest square planar geo metry for these complexes. The axial coordination in these complexes i s supported by their electronic spectra in dimethylformamide (DMF, a c oordinating solvent). Various ESR parameters for all copper complexes have been calculated showing an axial d(x2-y2) ground state. The elect rochemical behaviour of these complexes has been studied by cyclic vol tammetry. (C) 1997 Elsevier Science Ltd.