Multiaddressable Self-Assembling Organogelators Based on 2<i>H</i>-Chromene and <i>N</i>-Acyl-1,ω-amino Acid Units

Abstract

Multiaddressable organogelators are 3,3-diphenyl-3H-naphtho[2,1-b]pyrans covalently linked to sodium N-acyl-11-aminoundecanoate. These molecules have been designed to respond to changes to their environment. They are shown to act as efficient gelators for polar organic fluids, and obviously they exhibit a thermosensitive answer as low molecular mass organogelators. In these fluids, the aggregative properties are totally suppressed upon conversion to neutral carboxylic species. The gels of these carboxylate sodium salts are shown to be markedly affected by light irradiation. Supramolecular gelating assemblies can be disrupted by the photoinduced ring opening of the chromene subunit, so that the macroscopic flowing property is recovered. Upon a further thermal treatment, the system is reversibly converted back to the supramolecular network. Controlled gelation could be achieved using temperature, light, or acidity as external stimuli.