Synthesis of novel 16- and 18-membered tetraazamacrocycles and their coppertll), cobalt(II) and nickel(II) complexes

Abstract

The tetraamide macrocycles of the type L₁-L₂ have been synthesized by the condensation reaction of phthalic acid with primary diamines which on reduction with LiAlH₄ yields their corresponding tetraazamacrocycles L₃, and L₄, The Co(II), Ni(ll) and Cu(II) complexes of these ligands have been synthesized and characterized by elemental analysis, mass, IR, ¹H NMR, EPR and electronic spectroscopic techniques as well as molar conductance and magnetic moment data. An octahedral geometry around the metal ion is suggested for [ML₃X₂]- [ML₄X₂l [where M = Co(II) and Ni(II); X = Cl or NO₃] while a square planar geometry is proposed for [ML₃]X₂ - [ML₄]X₂ [M = Cu(II); X=Cl or NO₃].