Imidazolium-based ionic liquid supported layered silicate HUS-7 as an active catalyst for ring opening of oxiranes

The use of supported ionic liquid catalysts has gained popularity as they can address the limitations of conventional ionic liquids (ILs). Therefore, in this study, two supported ionic liquids (SILs) through a wet impregnation approach were developed, where 1-ethyl-3-methylimidazolium tetrafluoroborate (C(2)mim BF4) and 1-hexyl-3-methylimidazolium chloride (Hmim Cl) were immobilized on layered silicate material, specifically HUS-7, to produce a novel catalyst. The binding of the ILs with layered silicate HUS-7 was confirmed using various characterization techniques (XRD, FE-SEM, H-1 MAS NMR, N-2 isotherms), indicating strong interactions between each IL and layers of HUS-7. A detailed structural analysis of the SILs was conducted using ATR-IR spectroscopic techniques in conjunction with quantum chemical calculations. Despite the different cationic and anionic parts of the chosen ILs, almost similar activity was observed. The outcomes show a strong heterogeneous catalyst was produced as a result of ILs' interaction with layered silicate. To ascertain the robustness of each synthesized catalyst, the reusability and structural analyses of the used catalysts were also performed.

Automated summary

Supported ionic liquid catalysts were developed by immobilizing 1-ethyl-3-methylimidazolium tetrafluoroborate (C(2)mim BF4) and 1-hexyl-3-methylimidazolium chloride (Hmim Cl) on layered silicate material. Characterization techniques confirmed strong interactions between the ILs and the layered silicate. A detailed structural analysis was conducted using ATR-IR spectroscopy and quantum chemical calculations. The synthesized catalysts showed similar activity despite the different cationic and anionic parts of the ILs.