Synthesis of Complexes of Some Transition Metals with Nitrogen Donor Macrocyclic Ligands

New mononuclear iron(III), cobalt(II) and nickel(II) macrocyclic complexes of the general formulae [M(L)X2] [where M = Co(II) and Ni(II)] and [Fe(L)X2]X [L = 5,9‐dioxo‐3,4,7,10,11,17‐hexaaza‐2,11,13,15,1(17)‐N‐pentadienebicyclo[3,11,11,13]heptadecane; X = Cl, NO3, OAc or 0.5 SO4] were synthesized. The complexes were characterized on the basis of elemental analyses, atomic absorption, magnetic moment measurements, UV–Vis and infrared spectral studies. All the complexes were found to have octahedral geometry.