Supramolecular Gels Based on -Symmetric Amides: Application in Anion-Sensing and Removal of Dyes from Water.

We modified -symmetric benzene-1,3,5--amide (BTA) by introducing flexible linkers in order to generate an N-centered BTA (N-BTA) molecule. The N-BTA compound formed gels in alcohols and aqueous mixtures of high-polar solvents. Rheological studies showed that the DMSO/water (1:1, /) gels were mechanically stronger compared to other gels, and a similar trend was observed for thermal stability.

The Role of Functional Groups in Tuning the Self-Assembly Modes and Physical Properties of Multicomponent Gels.

We have analyzed the nature and role of functional groups on the self-assembly modes and the physical properties of multicomponent gels with structurally similar individual components. The gelation properties of individual and mixed enantiomeric compounds of biphenyl bis-(amides) of alanine (BPA) or phenylalanine (BPP) methyl ester were analyzed in various solvent/solvent mixtures. Multicomponent gels were formed by mixing the enantiomeric BPP compounds at a lower concentration, but a higher concentration was required for mixed alanine-based BPA gels.

Stimuli-Responsive Properties of Supramolecular Gels Based on Pyridyl--oxide Amides.

The nature of functional groups and their relative position and orientation play an important role in tuning the gelation properties of stimuli-responsive supramolecular gels. In this work, we synthesized and characterized mono-/bis-pyridyl--oxide compounds of -(4-pyridyl)nicotinamide (-). The gelation properties of these -oxide compounds were compared with the reported isomeric counterpart mono-/bis-pyridyl--oxide compounds of -(4-pyridyl)isonicotinamide.

Making and Breaking of Gels: Stimuli-Responsive Properties of Bis(Pyridyl--oxide Urea) Gelators.

The structural modification of existing supramolecular architecture is an efficient strategy to design and synthesize supramolecular gels with tunable and predictable properties. In this work, we have modified bis(pyridyl urea) compounds with different linkers, namely hexylene and butylene, to their corresponding bis(pyridyl--oxide urea). The gelation properties of both the parent and the modified compounds were studied, and the results indicated that modification of the 3-pyridyl moieties to the corresponding 3-pyridyl--oxides induced hydrogelation.