LEVULINIC ACID. II. THE VAPOR PRESSURES OF ITS ALKYL ESTERS (C₁--C₆

Esterification of levulinic acid with butanol over ion exchange resins

“…Literature on BL synthesis is sparse: first attempts at synthesis were undertaken with homogeneous catalysts [17][18][19], and a kinetic model for the esterification of LA with butanol (BuOH) was proposed by Bart et al [37]. Some work has been made in BL production directly from cellulose with homogeneous catalysis [41].…”

“…Levulinate esters can be obtained by direct esterification of levulinic acid with alcohols, typically acid catalyzed (Scheme 1). Sah [17], and later Schuette [18] and Cox [19] were the first to synthesize alkyl levulinates by direct reaction between the acid and the alcohol; publishing the formation of a number of alkyl levulinates in excess of the corresponding alcohol in the presence of HCl. These early studies employed mostly homogeneous catalysis, and reported yields were low (35-75%).…”

Production of levulinic acid and alkyl levulinates: a process insight

“…The simplest pathway to synthesize levulinic esters is the direct esterification of levulinic acid, using various acid catalysts and involving alcohols as reactants as well as solvents. Since the first attempts at synthesis using homogeneous acid catalysts in 1930s, such as HCl in excess of the corresponding alcohol, [66][67][68] the study of levulinic acid esterification has progressed towards the use of heterogeneous catalysts, due to their greater sustainability in terms of recyclability, regeneration, corrosivity and toxicity, reflecting some of the Principles of Green Chemistry such as "Prevention", "Design for Degradation", "Design for Energy Efficiency". Using acid catalysts, the reaction mechanism considers the coordination of the carbonyl oxygen with the catalyst.…”

Contribution to the production and use of biomass-derived solvents – a review

“…One issue in the one-pot reaction may be the low selectivity achieved of AL, but, in comparison to dehydration/hydration reaction to obtain biomass derivatives and further convert them into AL, reactions of biomass performed directly in alcohols can protect highly reactive intermediates and prevent unwanted polymerization reactions, improving the yields of the required products [69,100,102]. About the potential use of AL as solvents, The group of Sah and that of Schuette published some physical and all soluble in classical solvents (e.g., alcohols, ethers and chloroform), but insoluble in water (except methyl levulinate) [103,104]. Lomba et al [93] measured the vapor pressures of alkyl levulinates and the values obtained their easily handle in relation to chlorinated solvents that present vapor pressures more than 400 kPa at the same temperature.…”