Synthesis and characterization of N-(I-Morphlinobenzyl) semicarbazide Manganese (II) and Iron (II) complexes

Abstract

The interaction of ethanolic solution of semicarbazide hydrochloride, benzyldehyde and morpholine yielded N-(I-Morpholinobenzyl) Semicarbazide Schiff base. The Schiff base complexes of manganese(II) and iron(II) were synthesized by refluxing the mixture of ethanolic solutions of the Schiff base and metal(II) chlorides, respectively. These complexes were characterized by gravimetry, spectrophotometry, potentiometry, molar conductance and infrared analyses. The Schiff base and the complex compounds are not soluble in water, slightly soluble in most common organic solvents but are readily soluble in methanol and ethanol. The molar conductance of the manganese(II) and iron(II) Schiff base complexes measured are 3.78 and 6.90 ohm-1cm2mol-1, respectively, indicating their non-electrolytic nature. The potentiometric studies revealed a pKa of 5.40 for the Schiff base. The standard Gibb’s free energy of Mn(II) and Fe(II) Schiff base complexes determined are -65.79KJmol-1 and -60.35KJmol-1, respectively. The ratio of metal ion to Schiff base determined potentiometrically and spectrophotometrically for the complex compounds is 1: 2. The IR spectrum of the Schiff base shows bands observable in the two Schiff base complex compounds, indicating the coordination of the Schiff base to the copper ion.

Key Words: Schiff base, azomethine, benzyldehyde, potentiometry, spectrophotometry, semicarbazide hydrochloride, morpholine.