New methodology and synthesis of non planar push pull chromophore molecules

Abstract

The study presented in the thesis is an expansion of the synthetic methodology and applications of the organic molecules having the and#960;-conjugated framework. The thesis involves mainly i) synthesis and characterization of donor-acceptor molecules, ii) study on self-assembling properties of small organic molecules and iii) applications in photophysical, biological and environmental applications more specifically in scavenging of NO in biology and water remediation. The study starts with a brief introduction to current work with the literature review on various synthetic strategies and applications of the donor-acceptor molecules. The initial findings include synthesis and application of a new family of push-pull chromophore molecules by the well-known [2+2] CA RE (cycloaddition-retroelectrocyclization) between a urea substituted donor alkyne and the acceptor 7,7,8,8-tetracyanoquinodimethane (TCNQ). The newly prepared push-pull chromophores are studied for their structural properties with different donor substituents. Further, the molecules were tested for their nitric oxide (NO) radical scavenging activity in vitro and in vivo (this part of the study is not presented in this thesis). Next phase of the thesis involves developing a greener methodology for the synthesis of donor-acceptor molecules by introducing the micellar chemistry. The conventional organic solvents used for the [2+2] CA RE reaction were replaced by water/surfactant mixture. Along with the conventional [2+2] CA RE product, a new reactivity was observed forming two different heterocyclic compounds, which were confirmed to be structurally analogous to certain drug molecules. The new reactivity is majorly attributed to the self-assembling behaviour of the surfactant molecules into certain supramolecular structures (vesicles or bilayers). Last part of the thesis involves an exploration of the self-assembling properties of bis and mono-substituted ethynyl urea molecules into different supramolecular micro/nanostructures.