摘要:
The present invention relates to a method for preparing a dialkyloxydianhyrohexitol (dimethylisosorbide) composition by etherification of dianhydrohexitol (isosorbide). The aim of the invention is to achieve a "clean" method that avoids the use of a methylation agent such as dimethyl sulfate or methyl chloride, which generate stoechiometric quantities of salts, or expensive dialkyl-carbonates, wherein only one of the two methyl groups participates in the preparation of mixed isosorbide ethers. Said 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 BrØnsted acid properties. The present invention further relates to a device for carrying out the method according to at least one of the previous claims, characterized in that said device includes a vaporization oven and a reaction oven.
摘要:
The present invention relates to a method for synthesising 2,5-furandicarboxylic acid (FDCA) from furan-2,5-dialdehyde (DFF). Said method is industrially applicable due to the simplicity and availability of the reagents used, and due to the experimental conditions on which said method is based: the method requires low temperatures and enables a reaction under atmospheric pressure, the reaction times being relatively short. Furthermore, the method does not lead to the formation of salts that need to be treated downstream from the method, and the catalytic ratio relative to the initial product is particularly low.
摘要:
The invention relates to a method for preparing a polycarboxylic composition, characterized in that it comprises a stage in which a monosaccharide composition undergoes an electrochemical oxidation treatment carried out in the absence of sodium hypochlorite and in the presence of a) an amine oxide and b) a carbon-based anode.Preferably, said anode is selected from the group comprising carbon felt and granular active carbon. The electrochemical oxidation treatment can be carried out advantageously at a pH, preferably of between 11.5 and 14. The inventive method makes it possible to obtain novel products, especially 2-carboxy-2, 3, 4-trihydroxypentane-dioicious acid, the salts and derivatives thereof.