65940-93-4Relevant articles and documents
Method for synthesizing isohexitol ester
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Paragraph 0010; 0043-0050; 0055-0056, (2021/05/05)
The invention discloses a method for synthesizing isohexitol ester, which is characterized in that a material containing hexitol and an esterifying agent is contacted with a solid acid catalyst in the presence of an aprotic solvent, and the isohexitol ester is obtained through one-pot one-step reaction. The method is especially suitable for the reaction of directly synthesizing the isohexitol ester, especially isosorbide ester, from hexitol, especially sorbitol, the total yield of the obtained isohexitol ester is 80% or above, and the yield of the isosorbide dicarboxylate reaches 60% or above.
Isohexide hydroxy esters: Synthesis and application of a new class of biobased AB-type building blocks
Thiyagarajan, Shanmugam,Wu, Jing,Knoop, Rutger J. I.,Van Haveren, Jacco,Lutz, Martin,Van Es, Daan S.
, p. 47937 - 47950 (2014/12/10)
Here we present the synthesis of a new family of sugar derived 1,4:3,6-dianhydrohexitol based AB-type monomers, containing one methyl ester group and a secondary hydroxyl group in all four possible stereo isomers (RR, RS, SR, SS). Structural characterization of the monomers (5a-d) was established by 1D and 2D NMR analysis, which was further confirmed by single-crystal X-ray structure determination. The application of these monomers in step-growth polymerization afforded fully isohexide based stereo-regular polyesters. Homo polyesters based on the RR and RS monomers were obtained with reasonable molecular weights by melt polymerization (Mn 2400 and 2500 resp.). These materials showed unexpectedly low glass-transition temperatures of 20°C and 15°C respectively. In contrast, the monomers with SR and SS configuration yielded only low molecular weight oligomers. Surprisingly, copolymerization of the RR and SR monomers gave a polyester with higher molecular weight (Mn 4100) and a high Tg of 80°C. These preliminary results show that isohexide hydroxyesters are an intriguing new class of biobased building blocks with many potential applications.
PRODUCTION OF 5-MEMBERED AND 6-MEMBERED CYCLIC ESTERS OF POLYOLS
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Page/Page column 10-11, (2010/01/12)
Described herein are improved methods for the preparation of 5- and 6-membered cyclic mono and diesters of sugar alcohols and anhydrosugar alcohols by reaction with an organic acid RCOOH over a solid acidic substrate. The process is adaptable to a continuous process for simultaneously making and separating the cyclic esters from the sugar alcohols and anhydrosugar alcohols under mild conditions using the solid acid substrate as both the catalyst and a chromatographic bed for separation. The reactions are performed at mild temperatures of 700C to 10O0C and the formation of the cyclic esters is nearly quantitative. Also described is a method for making 5- and 6-membered cyclic mono and diesters of sugar alcohols and anhydrosugar alcohols using microwave irradiation in the presence of the organic acid.