Isosorbide bis(methyl carbonate) synthesis from isosorbide and dimethyl carbonate: the key role of dual basic–nucleophilic catalysts

Abstract

Basic–nucleophilic nitrogenated organocatalysts catalyze the synthesis of isosorbide bis(methyl carbonate), with nucleophilicity having an influence twice as much as basicity on catalytic activity.

Reaction Mechanisms Applied to Starch Modification for Biodegradable Plastics: Etherification and Esterification

“…The synthesis of fatty acid starch esters in these studies proceeded by a nucleophilic substitution reaction between the electrophilic carbonyl carbon of vinyl carbonate and the hydroxyl group of starch, a nucleophilic functional group, via an acid-base reaction between cesium carbonate and vinyl carbonate (Scheme 10). Cesium carbonate was used as a catalyst in many studies related to the esterification of starch because of its higher solubility in polar solvents, such as N,N-dimethylformamide (DMF) and dimethylsulfoxide (DMSO), which can dissolve the reactant starch and carbonate compounds, compared to potassium carbonate or sodium carbonate [27].…”

The future of isosorbide as a fundamental constituent for polycarbonates and polyurethanes

“…Ochoa-Gómez et al (24) offered a very interesting approach to assess the influence of both the basicity and the nucheophilic character of a catalyst into the isosorbide conversion and the IBMC yield. They demonstrated that the IBMC production was very adversely influenced by the presence of residual acidic impurities resulting from the isosorbide synthesis by sorbitol dehydration using mineral acids such as sulfuric acid Scheme 2.…”

“…The petro-derived monomer is obtained from the catalytic condensation between phenol and acetone at 50-90°C in the presence of a strongly acidic catalysts with a ratio acetone:phenol of 1:3-30 (25). IBMC is obtained at similar temperatures but with basic catalysts and a ratio of ISO:DMC 1:30 (24). In both cases, the formation of undesired secondary products is an issue that must be still further optimized to decrease the purification costs.…”

“…If DMC is used as a reactant, temperatures for this first stage are close to the DMC reflux temperature. It is not necessary to use vacuum since the methanol produced is easily eliminated by distillation (19,24). On the other hand, if DPC is used with isosorbide, temperatures from 160°C to 220°C coupled with high vacuum must be considered to remove the phenol formed (32).…”

Acylamido-based anion-functionalized ionic liquids for efficient synthesis of poly(isosorbide carbonate)

“…Third, DMC can undergo both methylation and carboxymethylation reactions, [38][39][40] resulting in the formation of eight intermediates during the reaction with endo-OH and exo-OH of ISB, of which only the carboxymethyl intermediates are the preconditions for the synthesis of PIC (Scheme 1). 41,42 Thus, a suitable catalyst is indispensably needed to improve the reactivity of endo-OH and to minimize the selectivity to methyl intermediates for the PIC synthesis. Previously, Zhang et al screened some metal-based catalysts for balancing the reactivity of endo-OH and exo-OH with DPC.…”