13 results about "Cyanohydrin" patented technology

The present application relates to a preparation method of cyprosulfamide, and the cyprosulfamide is prepared by using a one-pot method, and the method specifically comprises the following steps: adding an organic base, a reaction solvent, 2-chloro-3-(2,2,2-trifluoroethoxy)methyl-4-methylsulfonylbenzoic acid and a Curtius condensing agent into a reaction container, heating and refluxing for 3-5 h to generate an active ester intermediate; after the reaction solution containing the active ester intermediate is cooled, 1,3-cyclohexanedione and acetone cyanohydrin are added to perform a condensation rearrangement reaction, and cyprosulfamide is generated. The one-pot synthesis process is adopted, the use of dimethyl sulfoxide is avoided, compared with a traditional process, the method is green, environmentally friendly, has low safety risks, has high yield and good purity, and is more suitable for industrialized production.

The application discloses a green synthesis method of cyanohydrin ester compounds, which comprises the following steps: mixing acyl cyanide, carboxylic acid, an activating agent and corresponding solvent, and then realizing deoxygenation esterification reaction of the acyl cyanide carbonyl under mild conditions, so as to obtain a series of cyanohydrin ester compounds. The application can efficiently realize efficient synthesis of the cyanohydrin ester compounds under mild conditions, and avoids releasing or converting CN — anions in the traditional reaction process. In addition, the reaction has high yield and simple operation, can realize amplification of the reaction, and has wide application prospect and practical value.

The invention relates to the technical field of alpha-hydroxyisobutyric acid synthesis, in particular to alpha-hydroxyisobutyric acid as well as a preparation method and a production system thereof. The method comprises the following steps: enabling an inert solvent and water-containing sulfuric acid to flow from a first reaction zone to a second reaction zone of an amidation reactor, and sequentially carrying out amidation reaction on the inert solvent and the water-containing sulfuric acid with acetone cyanohydrin in the first reaction zone and acetone cyanohydrin in the second reaction zone to obtain a first mixture; then carrying out deep reaction to obtain a second mixture; carrying out steam stripping treatment on the second mixture to obtain a mixed solution; carrying out a hydrolysis reaction on the mixed solution under an acidic condition to obtain a hydrolysis reaction solution; and carrying out countercurrent contact on the hydrolysis reaction liquid and an extraction agent to carry out extraction treatment to obtain an extraction liquid, and carrying out rectification separation on the extraction liquid to obtain an alpha-hydroxyisobutyric acid product. According to the preparation process disclosed by the invention, the requirement on the purity of acetone cyanohydrin is as low as 97%, the product yield is as high as 96%, and the product purity exceeds 99%.

The invention discloses a green and efficient preparation method of polysubstituted-2-cyanopyrrole, and belongs to the technical field of fine chemical synthesis, according to the method, alpha, beta-unsaturated ketone is taken as a substrate, acetone cyanohydrin is taken as a cyaniding reagent, ionic liquid is taken as alkali and a reaction solvent, and the polysubstituted-2-cyanopyrrole is synthesized at a certain temperature. The structural general formula of the prepared polysubstituted-2-cyanopyrrole is as shown in formula I, in the formula, R1 represents pheyl, thiophen, pyridine, 4-Me-pheyl, 4-OMe-pheyl, 2-Cl-pheyl, 3-Cl-pheyl, 4-Cl-pheyl, 4-CN-pheyl, 4-NO2-pheyl or nanthyl, R2 represents phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, phenyl, r2 represents Me or Et; r3 represents Me, Et or n-Pr; the raw materials used in the method are cheap and easy to obtain, the green, pollution-free and recoverable ionic liquid is adopted as alkali and a solvent, a volatile organic solvent does not need to be additionally added, the experimental operation is simple, the method is green and environment-friendly, the reaction time is short, the yield is high, and the application range of a substrate is wide.

The application relates to an industrialized preparation method and application of high-purity alpha-amino nitrile. The application belongs to the technical field of fine chemical synthesis. The purpose of the application is to solve the technical problems of low yield and purity, high cost and unsuitability for industrialized production of the existing alpha-amino nitrile synthesis method. The method of the application is as follows: taking imine as a substrate, alpha-amino nitrile is synthesized by reacting with acetone cyanohydrin under the action of an ionic liquid. The method of the application synthesizes a nucleophilic addition cyanyl product of a carbon-nitrogen double bond in one step at room temperature. By selecting the ionic liquid and reasonably controlling the proportioning of various substances, the reaction process is greatly accelerated, the high-efficiency synthesis of alpha-amino nitrile is realized, the purity of alpha-amino nitrile is remarkably improved, the substrate adaptability is good, and the method can be widely applied to the synthesis in the fields of medicines and the like in the industry and the academia.

The invention provides high-activity S-cyanohydrin lyase and application thereof, and particularly, the 103-site amino acid residue of wild-type S-cyanohydrin lyase is mutated, so that the expression of the mutant enzyme in escherichia coli can be remarkably improved, and the temperature does not need to be reduced during inducible expression, so that the preparation cost of the enzyme is remarkably reduced; the S-cyanohydrin lyase with improved catalytic activity is obtained by further mutating the 128 site and other sites, and experimental results show that the catalytic activity of the mutated S-cyanohydrin lyase in catalysis of addition reaction of m-phenoxybenzaldehyde (m-PBAld) and HCN is improved by more than two times compared with that of a wild type.

The invention relates to the technical field of chemical production, and particularly discloses a treatment method for preparing alpha-hydroxy carboxylic ester and byproduct ammonium bisulfate mixed salt through an acetone cyanohydrin method. According to the method, unreacted sulfuric acid in the mixed salt is used, water is dropwise added at a high temperature to be matched with the methanol-water mixture at the same time, so that monomethyl sulfate is fully hydrolyzed into sulfuric acid and methanol, a large amount of extra waste salt generated by decomposing monomethyl sulfate with strong base at a high temperature is avoided, and the dropwise adding water amount is controlled, so that monomethyl sulfate can be completely hydrolyzed, and the production cost is reduced. After ammonia gas is introduced into the saline water, concentration treatment is not needed, fertilizer-grade I-type standard ammonium sulfate can be obtained through direct centrifugation, the centrifuged ammonium sulfate mother liquor is not directly discharged out of the system, but continues to be circulated back to the system to be used for dissolving mixed salt obtained after high-temperature acidolysis, ammonium sulfate in the mixed salt continues to be recycled, resource utilization of the ammonium sulfate mother liquor is achieved, and the utilization rate of the ammonium sulfate mother liquor is increased. And no liquid hazardous waste is generated in the whole system, so that the method is a green, energy-saving and recycling treatment method, and has higher popularization and application values.

The invention relates to the technical field of titanium dioxide production, in particular to high-weather-resistance flame-retardant titanium dioxide as well as a preparation method and application thereof. The preparation method comprises the following steps: S1, adjusting the temperature and pH of titanium dioxide base material slurry, adding a phosphoric acid solution and an alkali solution in a parallel flow manner, introducing air at the same time, and curing; s2, adjusting the pH value of the slurry, adding an aluminum salt and a pH regulator in a parallel flow manner, introducing air at the same time, and curing; s3, adjusting the pH value of the slurry, washing with water, and drying to obtain a filter cake; s4, adding an organic alkaline acid-binding agent to adjust the pH value of the slurry, and then adding an acylation reagent to react; and S5, adjusting the temperature of the slurry, adding acetone cyanohydrin, reacting, adding organic acid to adjust the pH value of the slurry, and carrying out alcohol washing, flash evaporation and steam powder to obtain the high-weather-resistant flame-retardant titanium dioxide. According to the method, air-assisted inorganic coating is adopted, acetone cyanohydrin is adopted for organic modification,-CN groups are introduced to the surface of titanium dioxide, and the weather resistance and flame retardance of titanium dioxide are remarkably improved.

A process purifies ethylene cyanohydrin by incubating an industrial grade ethylene cyanohydrin product with at least one titanium(IV)alkoxide. Ethylene cyanohydrin products have purities >99% and have less than 0.05% of ethylene glycol (EG), and / or have a water content of less than 1000 ppm.

The invention relates to a 2-hydroxy-4-(methylthio) butyronitrile composition with storage stability and a preparation method of the 2-hydroxy-4-(methylthio) butyronitrile composition. The 2-hydroxy-4-(methylthio) butyronitrile composition comprises 2-hydroxy-4-(methylthio) butyronitrile and 300-3000 ppm of a compound as shown in a formula (1). The cyanohydrin composition has excellent storage stability, and the content of the cyanohydrin composition can be kept unchanged after the cyanohydrin composition is stored at room temperature for 30 days.

The invention relates to a preparation method of a fenerenone bulk drug, and belongs to the technical field of organic synthesis and bulk drug preparation. The preparation method comprises the following steps: condensing 4-bromo-3-methoxybenzaldehyde and 3-oxobutyronitrile to obtain an intermediate 1; carrying out dehydration cyclization on the intermediate 1 and 4-amino-5-methylpyridine-2-ketone to obtain an intermediate 2; performing O-alkylation on the intermediate 2 to obtain an intermediate 3; splitting the intermediate 3 through tartaric acid to obtain an intermediate 4; hydrolyzing the intermediate 4 to obtain an intermediate 5; and coupling the intermediate 5 to obtain the fenerenone bulk drug. According to the method, 3-oxobutyric acid 2-cyanoethyl ester is replaced by 3-oxobutyronitrile, the raw materials are cheap and easy to obtain, the synthesis cost and difficulty are greatly reduced, high-pressure reaction can be avoided, and the reaction safety and the production efficiency are greatly improved.

The invention belongs to the technical field of organic synthesis, and particularly relates to an aryl formyl pyrazole compound and a synthesis method thereof. The synthesis method comprises the following steps: uniformly dispersing an aryl formic acid compound as shown in a formula 1 and a pyrazole alcohol compound as shown in a formula 2 in an organic solvent, stirring at room temperature, and sequentially adding an organic alkali and an onium salt condensing agent, so that the aryl formyl pyrazole compound can be efficiently prepared, the yield of the target compound is as high as 93%, and the aryl formyl pyrazole compound can be prepared by modifying hydroxyl on a pyrazole ring. A prodrug of the drug molecule or a compound with potential biological activity is obtained; according to the method disclosed by the invention, esterification and rearrangement two-step reaction are completed by a one-pot method under a one-step condensation condition for the first time, reaction steps are effectively shortened, and the preparation cost is remarkably reduced while the atom economy is greatly improved. Meanwhile, the method effectively overcomes the harsh reaction conditions of using highly toxic pipe products such as acetone cyanohydrin and trimethylsilyl cyanide in the existing rearrangement technology, and overcomes the technical defects of complex substrate synthesis, limited range and the like.