Studies on Mn III complexes and their catalytic applications

Abstract

This thesis deals with synthesis of Schiff base complexes of Mn(III) and study on their newlinecatalytic applications. Firstly synthesis of the Schiff base ligands H2L1(urea and newlinesalicylaldehyde, H2L2(Ethylenediamine and 2-hydroxy-4-nitrobezaldehyde), H2L3(3- newlinehydroxybenzaldehyde and ethylene-di-amine), HL4 (2-aminophenol and p-anisaldehyde) and newlineHL4 (aniline and salicylaldehyde) are done followed by the preparation of Mn(III) complexes newlineusing synthesized ligands with different axial ligands like NCS-, N3- , Cl- and Br-. 4 series of newlineMn(III) complexes are synthesised. The first series included complexes of Mn(III) with ligand newlineH2L1(urea and salicylaldehyde), second series consisted of Mn(III) complexes with ligand newlineH2L2(Ethylenediamine and 2-hydroxy-4-nitrobezaldehyde), third series is of Mn(III) newlinecomplexes with ligand H2L3 (3-hydroxybenzaldehyde and ethylene-di-amine) and the fourth newlineand final series of Mn(III) complexes have been synthesized with two different ligands HL4 newline(2-aminophenol and p-anisaldehyde) and HL4 (aniline and salicylaldehyde). Each of the series newlineconsisted of 4 new complexes with different axial ligands of NCS-, N3-, Cl- or Br. Thus, total newline16 new Mn(III) complexes have been synthesized. All the complexes are then characterized newlinevarious spectroscopic techniques like UV-Vis spectroscopy, IR spectroscopy, NMR, Mass newlinespectroscopy and magnetic susceptibility measurements which have been used for the newlinecharacterization of these newly synthesized complexes and with the help of which, the tentative newlinestructure of these complexes has been proposed. newlineThe catalytic activity of these synthesized Mn(III) complexes are studies. The newlinedifferent oxidation reactions have been carried out using these complexes. Synthesized Mn(III) newlinecomplexes are employed in oxidation of different substrates such as benzyl alcohol, newlinebenzaldehyde, benzoin and aniline. All these synthesized complexes were found to be good newlinecatalyst for these conversion reactions. newlineThe synthesized complexes are used for the study of decolourization of different newlinedye molecule