Fluorescence and Gelation Properties of Cyanostilbene Derivatives

Molecules containing cyanostilbene have attracted interest for their variable fluorescence properties attributable to its cis-trans isomerization. Previous research has shown that synthesized V-shaped cyanostilbene amide derivative containing a tert-butyl group have gelation capability in a variety of solvents¹. The purpose of this project was to synthesize and explore the gelation and fluorescence properties of V-shaped cyanostilbene amide derivatives containing alkoxy groups. The starting material for this synthesis, 5-hydroxyisophthalic acid, has a substitution of the hydroxyl group for an alkoxy group. The two carboxylic acids were reacted with a cyanostilbene amine to result in the desired product. The synthesis of a derivative containing a butoxy group was successful; however, exploration of alternate syntheses resulted in another molecule that has shown gelation properties in water that exhibits a transition temperature between gel and solution. The presence of water, acetonitrile, or methanol can influence the fluorescence of the solid to emit a green, blue, or yellow color, respectively. This molecule exhibits several characteristics that require further exploration. With additional research, such derivatives could be applicable as a separation basis between organic and aqueous phases as well as use in sensory applications.

Reference:

1. Zhang, Y., Liang, C., Shang, H., Ma, Y., & Jiang, S. (2013). Supramolecular organogels and nanowires based on a V-shaped cyanostilbene amide derivative with aggregation-induced emission (AIE) properties.Journal of Materials Chemistry C, 2013(1), 4472-4480. doi: 10.1039/c3tc30545g