Isosorbide. Preparation, Properties and Chemistry

Abstract

Isosorbide is obtained by dehydration of sorbitol and therefore can be considered as a valuable product from biomass. The acid‐catalyzed reaction gives rise to different anhydro‐compounds, but also to polymer‐like products. Kinetics of sorbitol decrease, followed with the help of HPLC, shows, remarkedly, the different reactions taking place during the dehydration. Physiocochemical properties of isosorbide are also discussed: melting temperature, specific gravity, solubility. Emphasis is put on stereochemistry aspect, pointing out the endo‐exo position of hydroxyl groups versus those of other isomers: exo‐exo for isoiodide and endo‐endo for isomannide. Some other properties such as: hygroscopicity ant thermal stability are also discussed. The chemical reactivity of the molecule is then described and some reactions analyzed, proving the interest of the cyclic conformation. Finally, a review of known applications is presented.

Cellulose Conversion to Isosorbide in Molten Salt hydrate Media

“…In addition, intermolecular dehydration of sorbitol to oligomers, decomposition, and charring side reactions occur. [23] We discovered that ZnCl 2 hydrate media alone or with additional catalysts, such as CuCl 2 and NiCl 2 allowed a clean dehydration of glucitol into mainly isosorbide, at mild conditions. At a 90 min reaction time, 1808C, 4.0 MPa (hydrogen), glucitol to ZnCl 2 hydrate ratio of 1:12 (w/w), a molar ratio of CuCl 2 to glucitol of 0.5:1, and a 70 wt % ZnCl 2 salt hydrate, glucitol was fully converted to more than 95 % isosorbide.…”

One-pot Conversion from Lignocellulosic Biomass to Isosorbide

“…Sorbitol can be dehydrated into 1,4-anhydrosorbitol (1,4-AHSO) and 1,4-AHSO can be dehydrated into isosorbide using acid catalysts such as sulfuric acid 19) , sulfated zirconia 33) , and zeolite 34) . Amberlyst 70 is an ion-exchange resin, which can also catalyze sorbitol dehydration as a solid acid ( Table 3).…”

Engineering of alanine dehydrogenase from Bacillus subtilis for novel cofactor specificity

“…Whereas RasADH hardly shows stereochemical preference for alcohols with less-restricted configuration, for example, (R/S)-1-phenylethanol [24], this might be explained by the higher nucleophilic character of this hydroxyl substituent in isosorbide because of its intramolecular hydrogen bond to the ether O atom of the opposite tetrahydrofuran ring, which is in close spatial proximity [45,46]. On the other hand, the formation of DAI as main end product (Fig.…”