Supramolecular Chirality Induced by Self-Assembly in Novel Quinoid Conjugated Molecules

Molecular assemblies with supramolecular chirality have been developed for decades due to their distinctive chiroptical properties. Among the versatile approaches to induce supramolecular chirality, self-assemblies using non-covalent interactions have considered as a great potential for applying biological field and chiroptical devices owing to their high tunability and controllability.<br/><br/>In this work, we designed and synthesized novel quinoid conjugated molecules QuEDOT-(S)-Cn and QuPheDOT-(S)-Cn employing enantiopure alkyl side chains. Quinoidal moieties are suitable for constructing supramolecular chirality through self-assembly due to their strong π-π stacking property of highly planar structure. QuEDOT-(S)-Cn and QuPheDOT-(S)-Cn had different chiroptical properties in solution and film states depending on the external stimuli (solvents, temp) as well as different chemical structures. Then we conducted diverse analyses such as AFM, POM, SEM, CD, GIWAXS to determine the reason for the difference in anisotropic factors between two molecules. We will explain and discuss the relationship between the behavior of supramolecular chirality and chemical structures. These results suggest chemical designing strategies of organic semiconducting materials in forming supramolecular chirality using self-assembly.