A polyhedral oligomeric silsesquioxane-based catalyst for the efficient synthesis of cyclic carbonates

Abstract

Polyhedral oligomeric silsesquioxane functionalized with imidazolium chloride peripheries IJPOSS-Imi) was\ud successfully synthesized through a novel synthesis protocol. The solid was extensively characterized via 1H\ud NMR, 13C NMR and IR spectroscopy as well as combustion chemical analysis, mass spectrometry and transmission electron microscopy. Moreover, an in-depth investigation through 29Si NMR was performed.\ud POSS-Imi was used for the first time as a catalyst for the conversion of CO2 and epoxides into cyclic carbonates with excellent results in terms of both yield and selectivity. The catalyst displayed improved catalytic performance with respect to unsupported 1-butyl-3-methylimidazolium chloride. The enhanced activity was ascribed to the proximity effect generated by the increased local concentration of imidazolium\ud species surrounding the inorganic silsesquioxane core

Octa‐imidazolium POSS/quaternized polysulfone composite anion exchange membrane for alkaline fuel cell

“…The “a” and “c” labeled methylene protons appear as triplet at 0.84 ppm and 3.56 ppm respectively. Whereas “b” labeled methylene protons which is flanked between “a” and “c” protons appear as a pentet at 1.91 ppm . After the iodination, in I‐POSS “c” labeled methylene protons shifted to 3.20 ppm in spectrum (Fig.…”

The Role of Water Revisited and Enhanced: A Sustainable Catalytic System for the Conversion of CO2 into Cyclic Carbonates under Mild Conditions

“…[5] Many highly active and selective metal-based catalysts containing Lewis acid sites have been reported, such as metal complexes [10] and metal-organic frameworks (MOFs). [1,12] Several metal-free organic catalysts have also been investigated, such as ammonium halides, [1,[13][14][15] phosphonium halides, [3,16] and imidazolium-basedi onic liquids, [17][18][19] in which the halidesa re the catalytic speciesa cting as nucleophiles. [1,12] Several metal-free organic catalysts have also been investigated, such as ammonium halides, [1,[13][14][15] phosphonium halides, [3,16] and imidazolium-basedi onic liquids, [17][18][19] in which the halidesa re the catalytic speciesa cting as nucleophiles.…”

Bi-functional heterogeneous catalysts for carbon dioxide conversion: enhanced performances at low temperature

“…8 To achieve an easy recovery from the reaction mixture and reuse of the catalyst for multiple cycles, most of these salts were also heterogenized 9 on different supports. Silica-based porous materials, 10,11 polymers, 12,13 single as well as multi-walled carbon nanotubes, [14][15][16] and more recently carbon nanohorns 17 among others were already selected for this purpose. The mechanism of the reaction is well known and was already reported in various publications.…”