Liquid crystal gelators based on tetrathiafulvalene supramolecular assemblies: Synthesis, characterization and potential application

We synthesized a series of novel liquid crystal (LC) gelators by attaching two cholesterol groups through two ω-thioalkanoyloxy spacers of varying length to thia-crown-annulated tetrathiafulvalene (TTF) moieties (1a–e). Among these compounds, 1b and 1d underwent gelation to form stable supramolecular gels in various organic solvents, and their self-assembled morphology and structure indicated that Van der Waals interactions were the driving force of gel formation. In addition, more than half of the gels (1a–d) transformed into nematic LCs in a certain temperature range, while gelators that did not crystallize during cooling from the isotropic melt formed glassy mesogens. Notably, gelators obtained from n-hexane readily adsorbed rhodamine B in solution, which was considered useful for removing toxic dye molecules in wastewater. LC molecules described herein were capable of gelation and have useful oxidation and stimulus-responsive properties. They may therefore be useful for developing sensors and optoelectronic materials.