A series of multifunctional pivalamide based Low Molecular Mass Gelators (LMOGs) with potential applications in oil-spill remediation and toxic dye removal

Abstract

Designing new Low molecular weight gelators (LMOGs) which can congeal organic/aqueous solvents is a daunting task, especially those capable of selective organogelation in presence of oil/water systems. Phase selective organogelation (PSOG) offers various advantages over conventional methods for oil spill remediation, viz. programmability, responsiveness and biocompatibility. Molecules with multiple fragments such as one-dimensional hydrogen bonding groups, terminal bulky group and a variable organic moiety (aromatic, aliphatic, alicyclic) appear to be good candidates for design of new LMOGs. In this work, a new series of pivalic acid based amides (1A–13A) having aromatic, aliphatic and alicyclic backbones were synthesized and characterized by various physicochemical methods. All the compounds were exploited for their ability to congeal various organic solvents including crude oil fractions, fuels and oils. Out of 13 newly synthesized compounds, six turned out to be excellent organogelators. Multifunctional properties of these compounds were observed such as selective gelation of aliphatic solvents in presence of water and removal of dyes from aqueous medium with good efficiencies. A detailed study is undertaken to establish the cause of gelation/non-gelation of solvents based on structure-property correlation using single-crystal X-ray diffraction, powder X-ray diffraction, Hirshfeld surface analysis, etc. Moreover, these compounds represent a class of one of the smallest molecules explored for the application of phase selective organogelation of fuel for containing oil-spills and dye adsorbing materials for water pollution control.