IR, ELECTRONIC AND EPR SPECTRAL STUDIES ON COBALT(II) COMPLEXES OF MACROCYCLIC LIGANDS

A series of new Co(II) complexes have been synthesized by template condensation with L^1(2,7,9,14- Tetraphenyl-1,3,6,8,10,13-hexaazacyclooctadecane and L^2(2,7,9,14-Tetrahydroxyphenyl- 1,3,6,8,10,13- hexaazacyclooctadecane. The bonding and stereochemistry of the complexes have been determined by elemental analysis, molar conductance, magnetic susceptibility, IR, UV-visible and EPR spectral studies. All complexes exhibit magnetic moments corresponding to three-unpaired electrons. The magnetic and spectral data indicate an octahedral geometry for all the complexes except [Co(L^2)](NO3)2 which is of four coordinate tetrahedral geometry.