Structural and spectroscopic study of novel tetradentate macrocyclic ligand type N4 and its complexes with CrIII, MnII, FeII, CoII, NiII ,CuII, PdII and CdII

Abstract EN

Ethylenediamine was reacted in the first step with 2,5–hexandion to produce the precursor [A], then [A] was reacted with diethylmalonate to give the new tetra dentate macro cyclic Ligand [H2L].This Ligand was reacted with some metal ions in ethanol to give a series of new metal complexes of the general formula [M(HnL)X]m (where : M = CrIII, n = 0, X = Cl2, m = -1 ; M = MnII, FeII, NiII, CuII, n = 1, X = Cl2 , m = -1 ; M = CoII, n = 0, X = Cl, m = -1 ; M = PdII, n = 0, X = 0, m = 0 ; M = CdII, n = 2, X = 0, m = +2.

All compounds were characterized by spectroscopic methods [I.R, U.V-Vis, HPLC, Atomic Absorption], microanalysis of elements (C.H.N) along with conductivity measurements.

From the above date the proposed molecular structure for CrIII, MnII, FeII, NiII and CuII complexes is octahedral, While CoII, PdII, and CdII form trigonal bipyramid, square planar and tetrahedral geometries respectively.