Synthesis of bio-additives: transesterification of ethyl acetate with glycerol using homogeneous or heterogeneous acid catalysts

Abstract

Uma nova rota catalítica, de potencial interesse prático para a produção sustentável de acetinas a partir do glicerol, é descrita. Acetato de etila foi transesterificado com glicerol, numa razão glicerol: A new catalytic route with potential practical interest to sustainable production of bioadditives from glycerol is described. Ethyl acetate was transesterified with glycerol, in the ratio glycerol:EtOAc 1:10, at 25 or 90 o C using 0.1 equiv. of H 2 SO 4 or TsOH, as homogeneous catalysts. H 2 SO 4 led to the total glycerol consumption in 2 h. In the equilibrium, attained in 9 h, 100% yield of a diacetin:triacetin (55:45) mixture was formed. Using Amberlyst TM 15 dry and Amberlyst TM 16 wet in 1:30 glycerol:EtOAc ratio and reflux at 90 ºC the total glycerol consumption was achieved in 2 and 10h, respectively. The lower reactivity of Amberlyst-16 wet was explained in terms of deactivation of acid sites and decrease in glycerol diffusion to the inner resin pores, both factors caused by adsorbed water. The kinetics of glycerol transformation and product distribution in the equilibrium in relation to the H 2 SO 4 , Amberlyst-15 (dry) and Amberlyst-16 (wet) catalyzed reactions were measured.

Expeditious Syntheses to Pharmochemicals 1,3-Dihydroxyacetone, 1,3-Dichloro-, 1,3-Dibromo- and 1,3-Diiodoacetone from Glycerol 1,3-Dichlorohydrin Using Homogenous and Heterogenous Medium

“…45 In addition, compound 7 has been used in the synthesis of iminolactones (antibacterial), 46 aldosterone inhibitors, 47 vinylcyclopropane 47 and propranolol hydrochloride (a drug used for heart treatment). 48 In our continuing interest in the developing new routes for obtainment glycerol derivatives with high added value, [11][12][13][14] we now wish to present reproductive synthetic routes to glycerol ketones 1,3-derivatives (1,3-dihydroxyacetone (1), 1,3-dichloroacetone (6), 1,3-dibromoacetone (7) and 1,3-diiodoacetone (8)) from bioglycerol, a green raw material. It is worth mentioning that these C3-ketones were synthesized via process intermediated by reagents supported on polymer resins or alumina, some of them under solvent free conditions.…”

“…7 Despite the diverse glycerol uses, its growing production could cause an excess in the market and an incalculable damage to the environment could be produced if inadequate glycerol disposal was carried out. [1][2][3][4][5][6][7][8][9][10][11][12] Thus, it is necessary to develop new strategies to add value to glycerol. Use of glycerol for the production of oxidized compounds such as 1,3-dihydroxyacetone (1,3-DHA (1)) is of great industrial interest.…”

Drug-Excipient Interactions: Case Studies and Overview of Drug Degradation Pathways

“…Transesterification is the process of exchanging the organic group of an ester with the organic group of an alcohol. These reactions are often catalyzed by the addition of an acid or base catalyst [27] also be accomplished with the help of enzymes (biocatalysts) particularly lipases. Strong acids catalyze the reaction by donating a proton to the carbonyl group, thus making it a more potent electrophile, whereas bases catalyze the reaction by removing a proton from the alcohol, thus making it more nucleophilic.…”

Drug-Excipient Interaction of Methylphenidate with Glycerin in Methylphenidate Oral Solution and Identification of its Transesterification Products by UPLC-MS/MS

“…There were several articles described the formation of glycerin transesterification products in which glycerin is tend to form 1-mono and 2-mono esters when reacts with esters [13]- [17]. The detailed mechanism for the formation of methylphenidate-glycerin esters were described in (Figure 8) [14]. The reaction of primary and secondary alcohols of glycerin with methylphenidate could be the possibility for the formation of these two impurities.…”