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.

N‐Acyl amino acids RCONH(CH2)nCOOR1 represent a new family of organogelators that can be obtained in a combinatorial approach from libraries of activated acids and amino acids. The amounts required for gel formation (see picture) in solvents such as DMF are less than 1 mg mL−1 and the gels formed are very stable. n=5, 7, 10, 12; R=aromatic or aliphatic group; R1=H or alkali metal (Na).

A new class of efficient low molecular weight gelator molecules has been designed by combining 11‐aminoundecanoic acid (AUDA), lauric acid and aromatic and aliphatic amino acid units in the same molecule. This yields a special class of fatty acid amphiphiles with core chiral centres and hydrogen bonding sites. Some of the compounds with terminal carboxylic acid and sodium carboxylate functions exhibited ambidextrous gelation properties, being able to form gels both with highly polar solvents (water, DMSO) and also with highly lipophilic solvents, including two hydrocarbon fuels. At variance with several recent observations that the enantiomers are generally more efficient gelators than the corresponding racemates, some of the racemic gelators prepared in this work were found to be capable of gelling up to 16 times larger volumes of certain solvents than the pure enantiomers. Temperature‐dependent FTIR and 1H NMR studies of the gels formed by derivatives with terminal carboxylic acid groups and lipophilic solvents revealed that intermolecular hydrogen bonding between amidic and carboxylic acid units was involved in the self‐assembly of gel aggregates. Additional strong stabilization of the aggregates was observed in the gelators possessing terminal sodium carboxylate groups, and this was attributed to the electrostatic and ion‐dipole interactions between the sodium carboxylate groups. This additional stabilization appears to be responsible for considerably higher thermal stability of the latter gels in relation to those formed by gelators with terminal carboxylic acid groups. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

This study reports on the gelation behaviour of a well-known family of dipicolinic acid derivatives that lack any long aliphatic chain as substituent. The mechanism of gelation is likely to arise from the base-assisted deprotonation of the carboxylic functionality which leads to the formation of the

The use of 11-aminoundecanoic acid as a synthetic building-block allows the systematic preparation of (oligo)amide organogelators-including chiral ones-which display remarkable gelation properties in organic solvents and water.