Synthesis and Characterization of N-Benzylidene Aniline Ligand for Spectrophotometric Determination of Nickel

Abstract

Schiff bases are compounds containing azomethine group (-HC=N-). They are condensation products of ketones or aldehydes (aldehydes and ketones) with primary amines. Formation of Schiff base generally takes place under acid or base catalysis or with heat. The spectrophotometric determination of metals using Schiff base metal complex is very important in analytical chemistry. This study has helped to establish a novel, simple and cheap analytical method for the determination of nickel in an environmental sample especially in developing countries where the cost and maintenance of sophisticated instruments are extremely high. In this study, Schiff base ligand was synthesized using benzaldehyde and aniline to form a metal complex with the target analyte (Ni²⁺). The melting point and electrical conductivity of the synthesized nickel complex were 175.6^oC and 84x10^-6Ώ^-1cm^-1respectively and the maximum absorbance at 360nm was 0.60. The complex was characterized using different spectroscopic techniques. The peak in FT-IR spectra at 1625.2 cm^-1 confirmed the (C=N) stretching vibration. The ¹³C and ¹H NMR spectra showed 193.8 and 10.0 ppm respectively of (CH=N) which was assigned to the azomethine carbon atom and the GC-MS analysis revealed a plausible structure of the complex. The stoichiometry of the Schiff base nickel (SB-Ni) complex was established as NiSB₂by Job’s method of continuous variation, mole- ratio and slope-ratio methods. The three procedures are in agreement over the stoichiometry of the SB-Ni complex.

Keywords: Complex, Stoichiometry, N-benzylideneaniline, Spectrophotometric, Ligand

DOI: 10.7176/CMR/11-10-04

Publication date: December 31^st 2019