Chromophoric Nitroso, Azo, Schiff Base Transition Metal Complexes, Synthesis and Studies

Abstract

This endeavor deals with the investigation of the Chromophoric nitroso, azo, Schiff base and transition metal complexes. In the first part of this dissertation, Schiff bases were designed, synthesized and characterized by contemporary techniques. These Schiff bases exhibited absorptions in visible region, i.e 393-405 nm. Metal complexes of these Schiff were synthesized using d-block transition metal ions and these complexes showed bathochromic shift with respect to Schiff base ligands and their absorptions were appeared at 410-455 nm. Anticancer activity was found to be good in case of palladium and copper complexes. Electrochemical analysis revealed that these Schiff bases and their complexes behave as oxidizing agents. Heterocyclic pyrazolone azo dyes were successfully synthesized. Newly synthesized dyes were characterized by UV-Visible, FTIR, and NMR, elemental analysis studies and their exhaustion, fixation and fastness properties have also been explored. Heterocyclic (pyrazolone) azo dyes have been prepared by changing the reaction pathway. In these dyes, first azo dyes are synthesized from different active methylene compounds and then their heterocycles have been synthesized by treating them with different hydrazines. Application of heterocyclic dyes on leather showed high light fastness, wash fastness and rub fastness values such as 4-5, 4-5 and 3-4 respectively, which are moderate to good. Exhaustion and fixation values of these dyes are also very high on account of their high attraction and substantivity with cotton fibers exception being those few dyes which lack suitable functional groups for interaction. Furthermore, the dyes containing sulfonic and methyl substituents exhibited an incredible degree of levelness after washing demonstrating the good diffusion and excellent affinity to the fabric. Chromium (III) complexes of these dyes were prepared and they showed high fastness properties as compared to ligand azo dyes. Nitrosopyrazolones were synthesized from newly synthesized pyrazolones and their metal complexes were prepared and characterized by contemporary techniques. Electrochemical and biological study of these compounds and metal complexes were conducted and promising results were obtained. The geometries of all the complexes were determined by the help of slope ratio method through UV-Visible spectroscopy.