32 results about "Cyanohydrin" patented technology

To provide a method for synthesizing a cyanide that is a precursor to a β-amino acid derivative having bulky optical activity, intended for peptide synthesis including a β-amino acid having bulky optical activity.SOLUTION: The present invention provides a method for synthesizing a cyanation product having a bulky tertiary alkylated structure and having optical activity, by reacting an α-haloamide having a bulky tertiary alkylated structure and having optical activity with a cyanohydrin in the presence of a copper catalyst.SELECTED DRAWING: None

The utility model discloses a condensate tank dead steam recycling device which comprises a supporting seat and a recycling box, a steam engine is installed on the upper surface of the supporting seat, a bearing groove is formed in the upper surface of the steam engine, the condensate tank dead steam recycling device further comprises a discharging box and a recycling mechanism, the discharging box is installed in the steam engine, and the recycling mechanism is installed in the bearing groove. The recycling mechanism comprises an air pump, a waste steam pipe, a control valve and a recycling box, a discharging pipe is installed at the lower right end of the discharging box, the cooling mechanism comprises a cooling box, a storage box, a heat absorption plate and a fan, the cooling box is installed on the right side of the steam engine, and the upper end of the cooling box is connected with a suction pump through the discharging pipe. According to the condensate tank dead steam recycling device, dead steam generated by machining can be recycled through the recycling mechanism, energy is directly discharged, recycling is conducted, the efficiency is improved, acetone cyanohydrin after machining is conveniently cooled through the cooling mechanism, feeding and discharging do not need to be conducted back and forth, condensate can be recycled through the circulating mechanism, and waste is reduced.

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 invention provides a preparation method of 17 alpha-hydroxypregna-4-ene-3, 11, 20-triketone and an intermediate compound prepared by the preparation method, and relates to the technical field of medicine synthesis. The target product disclosed by the invention is prepared by taking 11 alpha-hydroxy-4-androstenedione as a starting material and carrying out six-step reaction, namely oxidation, ethynylation, ketalation, sulfonylation, etherification and hydrolysis. The starting material 11 alpha-hydroxy-4-androstenedione of the process is prepared from 4-androstenedione through enzyme transfer, and compared with 11 alpha, 17 alpha-dihydroxyprogesterone prepared from 17 alpha-hydroxyprogesterone through enzyme transfer, the enzyme transfer technology of the former is more mature, the conversion rate and the yield are higher, and the cost is lower. Meanwhile, the preparation method disclosed by the invention is easy to operate and implement in production and high in reaction conversion rate, avoids the use of a highly toxic reagent acetone cyanohydrin, and is more beneficial to large-scale industrial 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 belongs to the technical field of herbicide production, and particularly relates to a synthesis method of tembotrions. The synthesis method comprises the following steps: taking 2-chloro-3-(2, 2, 2-trifluoroethoxy) methyl-4-methylsulfonylbenzoic acid as a starting material, reacting with a supported chlorinating agent under the catalysis of dimethylformamide to generate acyl chloride, carrying out condensation reaction on the acyl chloride and 1, 3-cyclohexanedione in the presence of an acid-binding agent to generate a condensation compound, and carrying out condensation reaction on the condensation compound and 1, 3-cyclohexanedione to obtain the 2-chloro-3-(2, 2, 2-trifluoroethoxy) methyl-4-methylsulfonylbenzoic acid. And carrying out transposition on the condensate under the catalysis of a transposition agent to generate tembotrione, and refining to obtain a pure tembotrione product. The synthesis method is a one-pot method, intermediate products do not need to be separated, the reaction conversion rate is high, and the product yield and purity are high. In addition, the reaction conditions of the synthesis method are mild, thionyl chloride and acetone cyanohydrin in the traditional process are abandoned, and the synthesis method is high in safety and environmentally friendly.

Disclosed is a process for the preparation of L-glufosinate-ammonium and / or a salt thereof or an alkyl ester of L-glufosinate-ammonium and / or a salt thereof wherein the L-glufosinate-ammonium or the alkyl ester of L-glufosinate-ammonium has a molecular structure according to formula (I) wherein R1 is H or a C1-C8 alkyl group; wherein the process comprises the step of reacting in at least one reaction step: (1) a cyanohydrin or a cyanohydrin derivative according to formula (II) wherein R1 is H or C1-C8 alkyl, and R2 is H, C1-C8 alkyl, C6-C10 aryl, C7-C10 aralkyl, C4-C10 cycloalkyl, or C1-C10 acyl; (2) an ammonia source; (3) a carbon dioxide source; and (4) at least two enzymes. # imgabs0 # (I) # imgabs1 # (II)

The invention belongs to the technical field of organic synthesis methodology, and particularly relates to a photoinduced beta-cyano sulfone compound synthesis method based on a triarylamine electron donor acceptor compound and application of the photoinduced beta-cyano sulfone compound. According to the method, a substituted sulfonium salt serves as an electron acceptor, triarylamine serves as an electron donor to form an EDA compound, and under the action of visible light, the EDA compound is synthesized into a beta-cyano sulfone compound based on the triarylamine electron donor acceptor compound. The method comprises the following steps: by taking substituted cyanohydrin as a raw material and 4-diazabicyclo [2.2. 2] octane di (sulfur dioxide) adduct [(DABCO). (SO2) 2] as a sulfur source, adding an organic solvent, reacting in an inert gas at a certain temperature, and realizing a bifunctionalization process of olefin through far-end functional group migration, thereby obtaining the beta-cyano sulfone compound. The method does not need harsh reaction conditions, the reaction can be completed in one step, the reaction conditions are mild, and the method is green and environment-friendly. The beta-cyano sulfone compound and the derivative thereof prepared by the method are expected to be applied to the research and development fields of anti-cancer, antiviral and antibacterial medicines and the like.

The invention discloses a preparation method of 2-methyl-4-acetylbenzoic acid, and relates to the technical field of production of 2-methyl-4-acetylbenzoic acid. 1-(4-fluoro-3-methylphenyl) ethanone is obtained from o-fluorotoluene and acetyl chloride under the catalytic action of AlCl and sulfonic acid functionalized mesoporous silica; the preparation method comprises the following steps: preparing 4-acetylbenzonitrile from 4-methylbenzonitrile under the action of a supported metal catalyst, then obtaining 4-acetyl-2-methylbenzonitrile under the action of 15-crown ether-5, PEG-400 and acetone cyanohydrin matched with CuI, and finally obtaining 2-methyl-4-acetylbenzoic acid under the action of oxygen and the supported metal catalyst. And the product has high yield and purity and is environment-friendly.

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 provides a cyclohexanone cyanohydrin synthesis process and a pilot plant, and belongs to the technical field of cyclohexanone cyanohydrin. The synthesis process of cyclohexanone cyanohydrin comprises the following steps: starting tail gas, firstly transferring cyclohexanone and diethylamine into a reaction kettle through a dropwise adding tank, dropwise adding hydrocyanic acid at a constant speed, controlling the reaction temperature, after the heat preservation reaction is finished, transferring the material into an acid adjusting kettle, dropwise adding 30% sulfuric acid, starting jacket hot water, maintaining the temperature at 45-50 DEG C, and carrying out negative pressure decyanation for 2 hours; and opening a jacket to circulate water, crystallizing, separating out lower-layer acid water and impurities, heating to 40 DEG C, and barreling after the product is crystallized and melted. According to the invention, the temperature is reduced to below 20 DEG C, the product cyclohexanone cyanohydrin begins to crystallize and separate out, and the residual raw material cyclohexanone has a hydrotropy effect, so that the crystallization temperature is different from the melting point; the unreacted raw materials of cyclohexanone, diethylamine sulfate, sulfuric acid and water can be separated out in a standing phase-splitting manner, and the method is simple, feasible, low in energy consumption, safe and environment-friendly.

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 present application relates to a kind of preparation method of furan sulfonyl ketone and its intermediate, with 2-chloro-3-methyl-4-methylsulfonyl benzoic acid as raw material, directly bromination is obtained 2-chloro-3-bromomethyl-4-methylsulfonyl benzoic acid;Then 2-chloro-3-bromomethyl-4-methylsulfonyl benzoic acid and tetrahydrofurfuryl alcohol substitution reaction is obtained 2-chloro-4-(methylsulfonyl)-3-(((tetrahydrofuran-2-yl) methoxy) methyl) benzoic acid;Then intermediate acyl chloride is formed;Acyl chloride intermediate and cyclohexanedione are condensed under the action of triethylamine, finally catalyst acetone cyanohydrin is added and rearrangement reaction is obtained target product furan sulfonyl ketone.Compared with prior art, the present application reduces the esterification protection of raw material 2-chloro-3-methyl-4-methylsulfonyl benzoic acid in the step of preparing furan sulfonyl ketone and the deprotection step in subsequent step, and the bromide removed in the reaction can be recycled and reused, shorten the reaction step, improve the overall yield, more green and environmental protection.

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 discloses a method for continuously synthesizing methacrylonitrile from acetone cyanohydrin, which comprises the following steps: (1) adding a catalyst into a reactor, introducing carrier gas, and heating to reaction temperature; (2) after the temperature is stable, introducing the raw materials and auxiliaries into a continuous reactor for reaction; and (3) performing condensation and gas-liquid separation on the product, and rectifying and purifying to obtain methacrylonitrile. According to the method for continuously preparing methacrylonitrile from acetone cyanohydrin, the yield of the product methacrylonitrile is high, the production cost is low, compared with a traditional method, the reaction condition is mild, few three wastes are generated, and the method is particularly suitable for industrial production.

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 utility model discloses a reaction tank for cyanohydrin production, which comprises a tank body, a plurality of feeding pipes are circumferentially arranged on the side wall of the tank body, inlet ends of the feeding pipes are communicated with different raw material tanks, outlet ends of the feeding pipes are provided with spray heads, raw material liquids sprayed by the spray heads intersect, booster pumps are arranged between the feeding pipes and the raw material tanks, and the booster pumps are communicated with the spray heads. A driving motor is arranged at the top of the tank body, the output end of the driving motor extends into the tank body and is connected with an airflow assembly in the tank body, the driving motor drives the airflow assembly to generate upward airflow, and the airflow acts on the ejected raw material liquid. According to the utility model, raw materials required by cyanohydrin production can be fully and uniformly mixed in the reaction tank, so that the neutralization reaction efficiency is improved, salt is fully dissolved in water, and the phenomenon that pipelines or valves of subsequent equipment are blocked due to crystallization and separation of fixed salt in the cyanohydrin production process is avoided.

A process for preparing L-glufosinate and / or a salt thereof or an L-glufosinate alkyl ester and / or a salt thereof, wherein the L-glufosinate or the L-glufosinate alkyl ester have a molecular structure according to formula (I) wherein R1 is H or C1-C8 alkyl, wherein the process comprises the step of reacting the following components in at least one reaction step: (1) a cyanhydrine or cyanhydrine derivative according to formula (II) wherein R1 is H or C1-C8 alkyl, and R2 is H, C1-C8 alkyl, C6-C10 aryl, C7-C10 aralkyl, C4-C10 cycloalkyl, or C1-C10 acyl; (2) a source of ammonia; (3) a source of carbon dioxide; and (4) at least two enzymes.

The invention relates to a synthesis method of stable isotope labeled 17alpha-hydroxypregnenolone 2, 3, 4-13C3, which comprises the following steps: S1, dissolving sodium cyanide in a solvent system, adding a phase transfer catalyst and dehydroepiandrosterone 2, 3, 4-13C3, stirring for catalytic reaction, and filtering to obtain a cyanohydrin intermediate I; s2, dissolving the obtained cyanohydrin intermediate I in another solvent system, adding methyl magnesium bromide under the protection of inert atmosphere, and stirring to carry out Grignard reaction; and S3, after the Grignard reaction in the S2 is finished, adding excessive sulfuric acid aqueous solution, stirring, carrying out hydrolysis reaction, and extracting, washing, drying, carrying out rotary evaporation and purifying the obtained product to obtain the 17alpha-hydroxypregnenolone 2, 3, 4-13C3 product. Compared with the prior art, the purity of the prepared 17alpha-hydroxypregnenolone-2, 3, 4-13C3 product is greater than or equal to 98%, the abundance is greater than or equal to 99atom% 13C, the abundance is not obviously diluted, and the like.

The invention discloses a preparation method of 2, 5-disubstituted-4-cyano imidazole, belongs to the technical field of organic synthesis, and particularly relates to a method for preparing 2, 5-disubstituted-4-cyano imidazole through a reaction of N-acyl imine and a cyaniding reagent under an alkaline condition, the structural general formula of the prepared 2, 5-disubstituted-4-cyano imidazole is shown as a formula I, in the formula I, R1 represents 4-Me-pheyl, pheyl, 4-Et-pheyl, 4-OMe-pheyl, 4-Br-pheyl, 4-CN-pheyl, 3-OMe-pheyl, 2-OMe-pheyl, 4-CF-pheyl, and thiope, and R2 represents a hydrogen atom, a hydrogen atom, a hydrogen atom, a hydrogen atom, a hydrogen atom, a hydrogen atom, a hydrogen atom, a hydrogen atom, a hydrogen atom, a hydrogen atom, a hydrogen atom, a hydrogen atom, a hydrogen atom, a hydrogen atom, a hydrogen atom, a hydrogen atom, a hydrogen atom, a hydrogen atom, a hydrogen atom, and a hydrogen atom. R1 represents phenyl, 4-Me-phenyl, thiope, 3-Cl-phenyl, 4-Br-phenyl, 4-Br-phenyl, 4-Me-phenyl, thiope, 3-Cl-phenyl and 4-Br-phenyl; compared with an existing 4-cyano imidazole synthesis method, the method has the advantages that the raw materials are cheap and easy to obtain, the operation is simple, and the 2, 5-disubstituted-4-cyano imidazole is prepared in one pot under the alkaline condition by taking a low-toxicity and low-price organic cyaniding reagent acetone cyanohydrin or trimethylsilyl cyanide as both a cyanogen source and a nitrogen source; the method provided by the invention is mild in reaction condition, high in product yield, good in purity, short in reaction time, good in substrate adaptability and strong in applicability.

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 present application belongs to the technical field of fine chemical synthesis. The purpose of the present application is to solve the technical problems of low yield, long reaction time, harsh reaction conditions and unsuitable for industrial production of the existing asymmetric conjugate cyanation addition reaction method for preparing optically pure beta-cyanoketone. The method of the present application: taking alpha, beta-unsaturated carbonyl compound as the substrate, taking acetone cyanohydrin as the cyan source, under the action of cinchona alkaloid derivatives, alkali and additives, without complicated operation, optically pure beta-cyanoketone is prepared in one step under the heating of nitrogen atmosphere. By screening the cinchona alkaloid derivatives, alkali, additives, reaction temperature and reaction solvent, and coordinating the optimal proportion of each substance, the side reaction is maximally inhibited, and beta-cyanoketone is obtained with high stereoselectivity and yield. The method of the present application has mild conditions, simple operation process and short reaction time, and has wide application prospect.

The invention discloses a micro-trans acetone cyanohydrin acylation reaction system and process, belonging to the technical field of acylation reactions. The reaction system comprises a sulfuric acid feed metering pump, an acetone cyanohydrin feed metering pump, a microchannel reactor, a gas-liquid separation tank, and a vacuum pump. The microchannel reactor is formed by coupling a micro-mixing module and a micro-reaction module, and a demister is provided in the gas-liquid separation tank. The invention realizes molecular-level mixing, has high mass transfer and heat transfer efficiency, avoids local overheating, reduces polymerization side reactions, effectively reduces the occurrence of side reactions, greatly improves the purity of reaction products, reduces the risk of microchannel reactor clogging, and improves resource utilization.

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 discloses a preparation method of 3, 5-disubstituted-2-cyano-1H-pyrrole, and belongs to the technical field of synthesis of fine chemicals, the method comprises the following steps: starting from alpha, beta-unsaturated ketone, taking low-cost and low-toxicity acetone cyanohydrin as a nitrogen source and a cyanogen source, and synthesizing 3, 5-disubstituted-2-cyano-1H-pyrrole in one pot under the conditions of certain temperature and solvent under the action of alkali, so that the yield of 3, 5-disubstituted-2-cyano-1H-pyrrole is increased, and the yield of 3, 5-disubstituted-2-cyano-1H-pyrrole is increased. According to the method disclosed by the invention, the reaction raw materials are cheap and easy to obtain; high temperature and strong acid conditions are not needed; a highly functionalized starting material is not required; meanwhile, acetone cyanohydrin is used as a cyanogen / nitrogen source, so that repeated charging is avoided; the used alkali is common and cheap, so that the use of transition metal and other expensive catalysts is avoided, and the cost is low; the product pyrrole N is free of fixed substituent groups, structural modification is facilitated, and the method is suitable for industrial production and has wide application prospects in the fields of preparation of drugs and intermediates and synthesis of functional materials.

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