6941-54-4Relevant articles and documents
Dimethyl isosorbideviaorganocatalystN-methyl pyrrolidine: scaling up, purification and concurrent reaction pathways
Annatelli, Mattia,Aricò, Fabio,Dalla Torre, Davide,Musolino, Manuele
, p. 3411 - 3421 (2021/06/06)
Dimethyl isosorbide (DMI) is a well-known bio-based green replacement for conventional dipolar solvents such as dimethyl sulfoxide and dimethylformamide. The synthesis of DMI mainly relies on the etherification of the bio-based platform chemical isosorbide in the presence of basic or acid catalysts and by employing different alkylating agents. Among them, dimethyl carbonate (DMC) is considered one of the most promising for its good biodegradability and low toxicity. In this work, we report on a comprehensive investigation on high yielding methylation of isosorbideviaDMC chemistry promoted by nitrogen organocatalystN-methyl pyrrolidine (NMPy). Reaction conditions were optimized and then efficiently applied for the methylation of isosorbide epimers, isoidide and isomannide, and for some preliminary scale-up tests (up to 10 grams of isosorbide). The purification of DMI from the reaction mixture was achieved by both column chromatography and distillation at reduced pressure. NMPy demonstrated to be an excellent catalyst also for the one-pot conversion ofd-sorbitol into DMI. Furthermore, for the first time, all seven methyl and methoxycarbonyl intermediates observed in the etherification of isosorbide were synthetised, isolated and fully characterised. This has provided an insight on the concurrent reaction pathways leading to DMI and on the role played by NMPy in the methylation of isosorbide. Finally, the reaction mechanisms for the methylation, methoxycarbonylation and decarboxylation promoted by NMPy partaking in the conversion of isosorbide into DMIviaDMC chemistry have been proposed.
Method for preparing dialkyloxydianhyrohexitol by etherification of dianhydrohexitol using a light alcohol, in the presence of an acidic catalyst
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Page/Page column 10-11, (2016/05/19)
A method for preparing a dialkyloxydianhyrohexitol (dimethylisosorbide) composition by etherification of dianhydrohexitol (isosorbide). The aim is to achieve a “clean” method that avoids the use of a methylation agent such as dimethyl sulfate or methyl chloride, which generates stoechiometric quantities of salts, or expensive dialkyl-carbonates, wherein only one of the two methyl groups participates in the preparation of mixed isosorbide ethers. The method involves using at least one O-alkylation agent and a catalyst including an acid or an acid salt, preferably a catalyst having Lewis or Br?nsted acid properties. A device for carrying out the method wherein the device includes a vaporization oven and a reaction oven is also described.
Green synthesis of dimethyl isosorbide
Tundo, Pietro,Aricò, Fabio,Gauthier, Guillaume,Rossi, Laura,Rosamilia, Anthony E.,Bevinakatti, Hanamanthsa S.,Sievert, Robert L.,Newman, Christoper P.
experimental part, p. 566 - 570 (2011/12/03)
A green synthetic approach for dimethyl isosorbide (DMI) with dimethylcarbonate (DMC) in the presence of a base is reported. The easy methylation of isosorbide may be due to its unique structure (which enhances the nucleophilicity of the hydroxyl groups), and to the effect of the hydrogen bonding which increases the reactivity of the molecule towards DMC.
