Synthesis of Tropine-Based Functionalized Acidic Ionic Liquids and Catalysis of Esterification

Abstract

Some traditional acidic ionic liquids (AILs) have shown great catalytic potential in esterification; meanwhile, the design and application of more new AILs are expected at present.Tropine-based functionalized acidic ionic liquids (FAILs) were synthesized to realize esterification catalysis for the first time; with aspirin synthesis as the template reaction, key influences on the substrate conversion and product yield of the synthesis, such as IL type, ratio of salicylic acid to acetic anhydride, temperature, reaction time and amount of IL, were investigated. The new tropine-based FAILs exhibited excellent performance in catalytic synthesis of aspirin with 88.7% yield and 90.8% selectivity. Multiple recovery and re-usage of N-(3-propanesulfonic acid) tropine is the cation, and p-toluenesulfonic acid is the anion. ([Trps][OTs]) shows satisfactory results. .When [Trps][OTs] was used to catalyze different esterification reactions, it also showed good results. The above studies proved that ionic liquid [Trps][OTs] could serve as an ideal green solvent for esterification reaction, which serves as a suitable substitute for current catalysts.

Multi-Component Syntheses of Spiro[furan-2,3′-indoline]-3-carboxylate Derivatives Using Ionic Liquid Catalysts

“…The use of ionic liquids (ILs) as organo-catalysts has recently received considerable attention [ 1 , 2 , 3 , 4 , 5 ]. More specifically, Brønsted acidic ILs are easy-to-make and versatile catalysts [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ].…”

Synthesis of isoamyl hexanoate catalyzed by deep eutectic solvent based on benzyltrimethylammonium chloride: RSM and ANN optimization and kinetics

“…Traditional esterification technology often uses concentrated sulfuric acid as a catalyst, 4,5 but concentrated sulfuric acid will cause serious corrosion to equipment and lead to a large amount of acid waste liquid in post‐treatment, which will cause environmental pollution. To avoid these disadvantages, the following catalysts have been developed: inorganic acids (such as boric acid), 6‐8 organic acids (such as p ‐toluenesulfonic acid, PTSA), 9,10 solid catalysts (such as solid superacid, 11‐13 sodium bisulfate, 14,15 heteropoly acid 16,17 and ion exchange resin 18,19 ) and ionic liquids 20‐25 . In particular, deep eutectic solvents (DESs) 26,27 are a special type of ionic liquids, which have the advantages of low cost and easy preparation.…”

“…To avoid these disadvantages, the following catalysts have been developed: inorganic acids (such as boric acid), [6][7][8] organic acids (such as p-toluenesulfonic acid, PTSA), 9,10 solid catalysts (such as solid superacid, [11][12][13] sodium bisulfate, 14,15 heteropoly acid 16,17 and ion exchange resin 18,19 ) and ionic liquids. [20][21][22][23][24][25] In particular, deep eutectic solvents (DESs) 26,27 are a special type of ionic liquids, which have the advantages of low cost and easy preparation.…”