6results about "Preparation from nitriles" patented technology

The application provides a method for preparing carboxylic acid by hydrolysis of nitrile, wherein the nitrile and protonic acid are subjected to hydrolysis reaction in a microwave reactor in the presence of solid inorganic medium to obtain the carboxylic acid; wherein the frequency of the microwave reactor is 0.9-3.0 GHz; the nitrile is aliphatic nitrile, aromatic nitrile or a mixture thereof; the relative dielectric constant ε of the solid inorganic medium is 30-500. r The application realizes microwave-high dielectric medium coupling reinforcement through the cooperation of the solid inorganic medium with specific relative dielectric constant and specific microwave reaction condition, can realize the efficient obtaining of high-purity carboxylic acid product, and produces ammonium salt as by-product. The overall method has high yield, strong raw material universality, is easy to be industrialized and amplified, and has remarkable economic effect.

The invention discloses a preparation method of 2, 6-dialkoxy or sulfenyl benzoic acid, and the synthesis route of the method is as follows: X1, X2, Y, R1 and R2 are defined in the specification. Compared with the existing process route, the preparation method disclosed by the invention has the characteristics of mild reaction conditions, simplicity in operation, low production cost, easiness in industrialization and the like.

The application belongs to the technical field of pharmaceutical chemistry synthesis, and particularly relates to a synthesis method of a fluorofelarana intermediate 2-methyl-4-acetylbenzoic acid. In the application, o-chlorotoluene and acetyl chloride are reacted under the action of anhydrous aluminum chloride to generate 4-chloro-3-methylacetophenone; the 4-chloro-3-methylacetophenone and acetonitrile are catalyzed by Ni to generate 4-acetyl-2-methylbenzonitrile; and then the 4-acetyl-2-methylbenzonitrile is hydrolyzed to generate 2-methyl-4-acetylbenzoic acid. The application has the beneficial effect that acetonitrile is used as a cyanogen to replace halogen, and a highly toxic cyanide is abandoned, so that the whole process is safer and more environmentally friendly, the production of three wastes is reduced, and the synthesis cost of 2-methyl-4-acetylbenzoic acid is greatly reduced.

The application discloses a continuous hydrolysis and extraction purification integrated process of 3-isobutyl glutaric acid, and relates to the technical field of 3-isobutyl glutaric acid. A micro-channel hydrolysis reaction liquid is generated; a high-dispersion acidification mixed liquid is obtained; a high gravity continuous mass transfer and liquid-liquid separation are carried out by using a high-speed rotating centrifugal field, a primary organic extraction phase rich in a target product is extracted; liquid-liquid complex washing is carried out under pulse oscillation, and a purified extraction phase is obtained; organic extraction solvent is gasified and stripped, and a supersaturated liquid material without solvent residue is collected at the bottom; under a multi-stage programmed cooling gradient, nucleation and crystal growth are induced, and a high-purity 3-isobutyl glutaric acid product is extracted after online solid-liquid separation. The application significantly improves the generation quality of a target intermediate and the robustness of a reaction system.

A process is described for preparing the compound of formula (S)-3 for optical enzymatic or chiral amine resolution of compounds of formula 4 wherein R is a cyano, carboxy or C1-C6 alkoxy carbonyl group and P is a protecting group of the hydroxy group.

The application belongs to the technical field of organic synthesis chemistry, and particularly relates to a fluorine-containing hydroxybenzoic acid compound and a preparation method. The application provides a novel synthesis path, which takes 4-fluoro-3-methoxybenzonitrile as a starting material, firstly performs specific demethylation reaction in benzene or toluene solvent through anhydrous aluminum chloride catalysis to obtain an intermediate 4-fluoro-3-hydroxybenzonitrile; then performs acid hydrolysis reaction on the intermediate in a mixed medium of concentrated sulfuric acid and water to convert the cyano group into a carboxyl group, and obtains 3-hydroxy-4-fluorobenzoic acid crude product; finally, high-purity product is obtained through directional recrystallization of an ethanol-water mixed solvent. The application fundamentally avoids competitive bromination and Grignard reagent application of a traditional route, and has the remarkable advantages of simple route, mild condition, safe operation, high selectivity, environmental friendliness and easy industrial implementation.