8 results about "Cyanoacetic acid" patented technology

The application discloses a catalyst for preparing malononitrile, a preparation method of the catalyst and a method for preparing malononitrile by using the catalyst. The catalyst is a solid catalyst, which is an acidic catalyst loaded with rare earth metal oxide. The method for preparing malononitrile is that cyanoacetic acid or cyanoacetate or cyanoacetamide and an ammonia source are subjected to ammoniation dehydration reaction in a continuous reactor to prepare malononitrile according to a certain molar ratio. Then, vacuum distillation (20 torr-25 torr) is carried out, and a fraction collected at 110 DEG C-120 DEG C is malononitrile product. The ammonia source can be ammonia gas, ammonia water, ammonium carbonate or urea. The method for preparing malononitrile can reduce production cost, improve production safety, reduce the discharge amount of three wastes in the preparation of malononitrile by using an existing process, and improve product quality, and is a sustainable and green synthesis route.

The invention provides a synthesis method of L-3-aminoisobutyric acid. The synthesis method comprises the following steps: enabling a dichloromethane solution of cyanoacetic acid to react with oxalyl chloride; a reaction product, (S)-4-benzyl-2-oxazolidinone dissolved in dichloromethane and triethylamine are respectively fed into a continuous flow reactor to be mixed and react with the (S)-4-benzyl-2-oxazolidinone dissolved in dichloromethane; collecting reaction liquid, extracting, concentrating and recrystallizing to obtain a compound 2; dissolving the compound 2 in tetrahydrofuran, and adding iodomethane; respectively feeding the mixed solution and a tetrahydrofuran solution of lithium diisopropylamide into a continuous flow reactor for mixing reaction; collecting reaction liquid, quenching and purifying to obtain a compound 3; dissolving the compound 3 in a mixed solvent of an organic solvent and water, adding lithium hydroxide and hydrogen peroxide, and reacting; adding a sodium sulfite aqueous solution for quenching reaction, extracting, concentrating and purifying to obtain a compound 4; dissolving a compound 4 in ethanol, and carrying out a continuous flow hydrogenation reaction with hydrogen through a continuous flow hydrogenation reactor; and collecting a reaction product, concentrating, cooling and crystallizing to obtain the L-3-aminoisobutyric acid.

The invention relates to a method for preparing (R)-4-((1-(2-cyanoacetyl) piperidine-3-yl) amino)-1H-pyrrolo [2, 3-b] pyridine-5-ethyl formate (compound 1). The process involves the addition of an ethyl formate group, the displacement of the halogen with a chiral amine, the deprotection of the chiral cyclic amine, and the subsequent coupling reaction with cyanoacetic acid. The displacement may be performed in an autoclave at elevated pressure.

The invention discloses a preparation method of a medical intermediate 2-(4-nitrophenyl) butyric acid, and belongs to the technical field of medical fine chemical engineering. According to the method, p-nitrochlorobenzene and alkyl cyanoacetate are used as raw materials to react to prepare an intermediate 2-cyano-2-(4-nitrophenyl) acetoacetate, and then the intermediate 2-cyano-2-(4-nitrophenyl) acetoacetate reacts with diethyl sulfate under the alkaline condition to obtain the 2-cyano-2-(4-nitrophenyl) butyric acid alkyl ester. And finally, hydrolyzing through a concentrated sulfuric acid and acetic acid mixed system to obtain the 2-cyano-2-(4-nitrophenyl) butyric acid. The raw materials and reagents used in the method are cheap and easy to obtain, the process is simple and easy to implement, and the cost advantage is remarkable. Meanwhile, the adopted reaction route does not generate isomeride impurities such as 2-(2-nitrophenyl) butyric acid and the like, the yield is high, and the quality of the obtained product is good.

The application belongs to the technical field of medicine synthesis, and particularly relates to a preparation method of tetrahydrozoline. The tetrahydrozoline is synthesized from trifluoromethylaniline and 2-cyanoacetic acid ethyl ester under the action of an alkaline catalyst, the method has mild conditions, simple and easy-to-operate post-treatment and purification, low energy consumption, short working hours, and is suitable for large-scale production.

The application discloses a kind of overcharge-preventing lithium battery electrolyte and its preparation method in the technical field of lithium ion battery, the electrolyte uses the composite system of carbonate solvent and fluorine-containing solvent, cooperates mixed lithium salt and two new additives: difluorocyclohexyl benzothiazolium hexafluorophosphate and 2,4,6-tri (cyanoacetic acid methyl ester group) -1,3,5-triazine.The preparation process includes solvent mixing, lithium salt dissolving, additive adding and multi-step purification process.Two additives are prepared by oxidation cyclization, quaternary ammonium and esterification, condensation reaction.The electrolyte has high conductivity and lithium ion transference number, high oxidation potential, good thermal stability, can effectively inhibit electrolyte decomposition and metal ion dissolution under overcharge condition, significantly improves the high-voltage stability and safety of lithium battery, and is suitable for high-voltage lithium battery, electric vehicle power battery and large-scale energy storage system and other fields.

The invention relates to an enadostat key intermediate and application of the enadostat key intermediate to preparation of enadostat, and belongs to the field of medicine preparation. The invention discloses preparation of key intermediate compounds 6 and 7, which specifically comprises the following steps: reacting a compound 1 with cyanoacetate under the action of an acid-binding agent to obtain a compound shown as a formula 6, and then reacting with benzyl chloride or benzyl bromide to obtain the intermediate 7. And when the method is used for the following reaction, the high-purity enadostat can be obtained without excessive post-treatment.

The specific preparation process comprises the following steps: dissolving a compound as shown in a formula (II) and cyanoacetic acid or rhodanine-3-acetic acid in a solvent, adding an alkali catalyst, carrying out a heating reflux reaction while stirring, and concentrating after the reaction is finished, so as to obtain a compound as shown in a formula (II); and dissolving the obtained concentrate in an eluent, separating and purifying through column chromatography silica gel, collecting the eluent, and evaporating to remove the eluent, thereby obtaining the target compound, and using the target compound to prepare the dye sensitizer. According to the present invention, benzothiadiazole is connected with two N-butyl carbazole electron donors, and an anchoring group and electron acceptor cyanoacetic acid or rhodanine-3-acetic acid is introduced onto benzothiadiazole, or a styrene bridge is connected with a cyanoacetic acid acceptor so as to synthesize the bis-carbazole benzothiadiazole compound, and a new applicable substance is added for screening the dye sensitizer.