Probing the supramolecular assembly in solid, solution and gel phase in uriede based thiazole derivatives and its potential application as iodide ion sensor.

[Display omitted] • Design of new gelator based on crystal engineering approach having urea functional group and thiazole moiety. • Seven gelators with varying aliphatic long chain were synthesized to realize delicate hydrophilic-hydrophobic balance. • Variable temperature SANS were used to understand the supramolecular packing of molecules in solid, liquid and gel phase. • Unprecedented high selectivity and sensitivity towards iodide ions was observed by urea containing gels. A simple series of thiazole-urea-aliphatic chain-based compounds (1–7) were designed and synthesized using the principle of Crystal Engineering. The aliphatic alkyl chain of compounds was varied to obtain the delicate hydrophobic-hydrophilic balance between solute–solvent molecules required to attain the supramolecular gelation. Interestingly, all the compounds turned out to be excellent gelators for polar solvents including water mixtures with alcohols and acetonitrile. To get an insight into the packing of molecules in solid-state, solution, and gel phases various physicochemical techniques were employed such as SANS, SEM, PXRD, DFT calculation, etc. UV–Vis spectrometric measurements of compound 1 in the solution phase were carried out to establish the anion sensing capability. Very high sensitivity and selectivity of iodide ion in presence of other ions and degelation of acetonitrile gel of compound 1 in presence of iodide salts, make these compounds a unique class of LMOGs. [ABSTRACT FROM AUTHOR]