SYNTHESIS AND COMPUTATIONAL STUDIES OF FREE-BASE meta-BENZIPORPHODIMETHENES AND THEIR METAL COMPLEXES

Abstract

This thesis begins with presenting a thorough review of m-BPDM analogues and their metal complexes. The literature review led us to the foundation of research gap. The studies were then diverted towards finding out the factors that could enhance the stability of the free base analogues of m-BPDM systems. Hence, in the next two chapters (4 and 5) the effect of substitutions at meso and C3-positions, studied computationally, has been presented. Molecular tailoring approach has been incorporated in order to find out the intramolecular hydrogen bond energies. The energies so obtained have been correlated with other factors obtained from the optimized geometry’s results, like the study of non-covalent interactions (NCI), frontier molecular orbital (FMO) visualization, molecular electrostatic surface potential (MESP) etc. We then moved to the synthesis of a new sterically hindered analogue of m-BPDM and its zinc and cadmium chloride complexes, viz. Chapter 6 of this thesis. The synthesis was confirmed by UV-Vis, 1H-NMR and mass spectrometry. The X-ray solid state structures stated the presence of two conformers of m-BPDM viz. syn and anti. It was found that crystal structures constituted varied conformers depending upon the group present at sp 3 meso carbon atoms. Thus, through chapter 7, we intend to understand the effect of substitution at meso-carbon atoms on the metalated (Zn(II) and Cd(II)) m-BPDM conformer stability.