Lipophilisation of Caffeic Acid through Esterification with Propanol Using Water-tolerable Acidic Ionic Liquid as Catalyst

Lipophilic antioxidant dodecyl caffeate preparation by the esterification of caffeic acid with dodecanol using ionic liquid [Hnmp]HSO4 as a catalyst

“…26,29 These indicated that, among all tested ILs, [Hnmp]HSO 4 was the best efficient catalyst for the esterification of CA with dodecanol, which was due to that the catalytic activities of ILs were relative to their acidities. 22,26,29 Compared with octadecyl caffeate preparation using cation-exchange resins (24 h, 95.17 ± 2.76%), 20 the time of DC preparation at 85 °C using [Hnmp]HSO 4 was reduced to 3 h, which showed that [Hnmp]HSO 4 had good performance for DC preparation by the esterification. In our previous work, we also used some immobilized lipases, Novozym 40086, Novozym TLIM, Novozym 435, and Candida rugose lipase, to catalyze the esterification to prepare DC.…”

“…Similar results that, the catalyst efficiency per unit of ILs decreased when excess ILs was presented in reaction system, can also be found in other IL-catalyzed reactions. 21,36 Compared with propyl caffeate preparation using [BSO 3 HMIM]TS (40% IL dosage), 26 the catalytic activity of [Hnmp]HSO 4 (10% IL dosage) to prepare DC was more efficient. Therefore, 10% IL dosage was used in the next experiments.…”

“…21–23 In the previous reports, some ILs had also been used as reaction solvents and catalysts for the short chain esters of alkyl caffeate synthesis. 14,24,25 Han et al 26 reported that propyl caffeate was synthesized using IL [BSO 3 HMIM]TS as a catalyst, and the maximum of propyl caffeate yield was 84%. Recently, due to the strong water absorbability, IL [Hnmp]HSO 4 showed good catalytic performance for some esterifications.…”

Synthesis of Daidzein Glycosides, α-Tocopherol Glycosides, Hesperetin Glycosides by Bioconversion and Their Potential for Anti-Allergic Functional-Foods and Cosmetics

“…Plant cultured cells can be used to convert organic molecules to more useful compounds by catalyzing hydrolysis, oxidation, reduction, esterification, isomerization, and glycosylation reactions. A recent paper reported that alkyl esters of caffeic acid, especially propyl caffeate, have stronger antioxidant activity than caffeic acid [24]. On the other hand, the glycosylation of bioactive compounds can enhance their water-solubility, physicochemical stability, intestinal absorption, biological half-life, and improve their bio- and pharmacological properties [25,26,27,28,29,30,31,32,33].…”

Lipophilization of Phenolic Acids through Esterification Using p-toluenesulfonic Acid as Catalyst

“…Though lipase catalysis can be conducted under mild reaction conditions, long reaction time (24-48 h), expensive price and sensitive lipase reagents limit their wide applications. Recently, it has been proved that p-toluenesulfonic acid (PTSA) has the potential to be used as a catalyst in conventional acidic catalytic system [10][11][12][13] . PTSA is characterized by the mildness of reaction conditions, inexpensive chemical and excellent functional group tolerance, which could afford the corresponding phenolic acid esters in high yields [10] .…”