15 results about "Chloroacetaldehyde" patented technology

The invention relates to an L-proline heterocyclic intermediate, alpha-methyl-L-proline hydrochloride and a preparation method thereof, which comprises the following steps: step 01, cyclization upper protection: taking L-proline as a raw material, which is shown in a formula (1), to react with trichloracetic aldehyde hydrate under an acidic condition, and performing upper protection to obtain a heterocyclic intermediate as shown in a formula (2); the molar weight of chloral hydrate is 1-2.5 times of the molar weight of the L-proline shown in the formula (1), preferably 1.5 times of the molar weight of the L-proline shown in the formula (1). 02, methylation: reacting the heterocyclic intermediate as shown in the formula (2) obtained in the step 01 with lithium diisopropylamide, and after the reaction is completed, adding dimethyl sulfate for methylation to obtain an intermediate as shown in a formula (3); 03, deprotection: adding the intermediate as shown in the formula (3) obtained in the step 02 into a deprotection reagent for hydrolysis so as to obtain the alpha-methyl-L-proline hydrochloride as shown in the formula (4), so that the problems that the preparation cost of the existing alpha-methyl-L-proline hydrochloride is relatively high and the yield is relatively low can be solved.

The invention relates to a bis (2, 2-methylene disulfide) episulfide compound with an ultrahigh refractive index and a preparation method thereof, and belongs to the technical field of optical materials, and the preparation method comprises the following preparation steps: taking chloroacetaldehyde dimethyl acetal, a solvent, disulfur dichloride and an acidifying agent, and carrying out a sulfuration substitution reaction to prepare 2-chloro-1, 2-dithiol; the preparation method comprises the following steps: carrying out nucleophilic substitution reaction on methoxycarbonyl sulfonyl chloride, a low-boiling-point solvent and 2-chloro-1, 2-ethanedithiol, and dropwise adding a bicarbonate saturated aqueous solution to carry out cyclization reaction so as to prepare a methoxycarbonyl disulfide-episulfide compound; and adding dimercaptomercaptan, and reacting to obtain a product. The process route provided by the invention solves the problems of tedious step-by-step reaction, more byproducts and high cost in the prior art.

The invention belongs to the technical field of medicine synthesis, and particularly relates to a preparation method of brexpiprazole. The preparation method comprises the following steps: by taking a compound 4-amino benzo [b] thiophene and chloroacetaldehyde as starting materials, carrying out substitution reaction to prepare an intermediate 2, 2 '-(benzo [b] thiophene-4-yl azane diyl) diacetaldehyde, and then carrying out reductive amination reaction on the intermediate 2, 2'-(benzo [b] thiophene-4-yl azane diyl) diacetaldehyde and 7-(4-amino butoxy) quinoline-2 (1H)-ketone to construct a piperazine ring, thereby preparing the target product bupremizole I, the product obtained by the process has high yield and purity, and is suitable for industrial production.

The invention belongs to the technical field of medicine synthesis, and particularly relates to a synthesis method of brexpiprazole. The preparation method comprises the following steps: taking compounds 4-amino benzo [b] thiophene and chloroacetaldehyde as starting materials, firstly carrying out reductive amination disubstitution reaction to prepare an intermediate N, N-bis (2-chloroethyl) benzo [b] thiophene-4-amine, then carrying out substitution reaction on the intermediate N, N-bis (2-chloroethyl) benzo [b] thiophene-4-amine and 7-(4-amino butoxy) quinoline-2 (1H)-ketone to construct a piperazine ring to prepare the target product brexpiprazole. The product obtained by the process has high yield and purity, and is suitable for industrial production.

This invention belongs to the field of organic chemical synthesis technology, specifically relating to a method for synthesizing 2-fluoro-3-aminobenzoic acid, an important chemical intermediate. Specifically, o-nitroaniline is condensed with hydrated trichloroacetaldehyde and hydroxylamine hydrochloride to obtain 2-(hydroxyimino)-N-(2-nitrophenyl)acetamide; the resulting product undergoes an intramolecular Beckmann rearrangement to generate 7-nitroindigo; 7-nitroindigo undergoes Bayer-Villedge oxidation to generate 2-amino-3-nitrobenzoic acid; 2-amino-3-nitrobenzoic acid undergoes diazotization and halogenation reactions to generate 2-fluoro-3-nitrobenzoic acid or 2-chloro-3-nitrobenzoic acid; 2-fluoro-3-nitrobenzoic acid can be further reduced by nitro to obtain 2-fluoro-3-aminobenzoic acid; or, 2-chloro-3-nitrobenzoic acid can be esterified to obtain 2-chloro-3-nitrobenzoic acid ester, which can then be fluorinated, saponified, and reduced to obtain 2-fluoro-3-aminobenzoic acid. The raw materials of this invention are low in cost and readily available, and the entire reaction route has specific regioselectivity, making it suitable for industrial production.

The application discloses a preparation method of 1,1,4,4-tetramethoxy-2-butene and application thereof, and belongs to the field of organic chemical synthesis. The method comprises the following steps: chloroacetaldehyde dimethyl acetal and triphenylphosphine are reacted to generate acetaldehyde dimethyl acetal phosphonium salt; and the acetaldehyde dimethyl acetal phosphonium salt is reacted with glyoxal monoacetal to generate 1,1,4,4-tetramethoxy-2-butene. The method is high in efficiency, environmental protection, simple in operation and friendly to the environment.

The invention discloses a method for detecting the content of chloroacetaldehyde in dimethylaminoacetaldehyde diethyl acetal, which comprises the following steps: carrying out precolumn derivatization on chloroacetaldehyde by using a derivatization reagent, and carrying out isocratic or gradient elution by using a reversed-phase high-performance liquid chromatography and an acetonitrile-phosphoric acid aqueous solution as a mobile phase. The method realizes accurate quantification of chloroacetaldehyde in dimethylaminoacetaldehyde diethyl acetal, is high in detection speed, low in cost and simple to operate, has good specificity, sensitivity, precision and accuracy, is an effective quality control method for dimethylaminoacetaldehyde diethyl acetal, and has wide application prospects. And the product quality of afatinib maleate bulk drugs and related preparations synthesized by using dimethylaminoacetaldehyde diethyl acetal as a starting material is further ensured.

The invention belongs to the crossing field of bioengineering and pharmaceutical technology, and particularly relates to a heterologous expression technology of 2-deoxyribose-5-phosphate aldolase derived from rhodococcus ruber SD3 and optimization of aldol condensation reaction conditions of substrates acetaldehyde and chloroacetaldehyde catalyzed by the aldolase. The enzyme can catalyze a substrate to specifically synthesize a statin drug key intermediate (3R, 5S)-6-chloro-2, 4, 6-trideoxy pyranoside, the conversion rate can reach 44.45%, and a new biological catalysis approach and technical support are provided for efficient and green production of statin drugs. The rhodococcus ruber SD3 is preserved in the China Center for Type Culture Collection, and the preservation number of the rhodococcus ruber SD3 is CCTCC NO: M 2012035.

The utility model relates to the technical field of chloroacetaldehyde dialkyl alcohol preparation, in particular to equipment for preparing chloroacetaldehyde dialkyl alcohol. The equipment for preparing the chloroacetaldehyde dialkyl alcohol solves the technical problems that the equipment for preparing the chloroacetaldehyde dialkyl alcohol in the prior art is complicated in structure, and a medium in a chlorination reactor is easy to leak. Equipment for preparing chloroacetaldehyde dialkyl alcohol comprises a chlorination reaction assembly and a reaction kettle assembly, and the chlorination reaction assembly supplies materials to the reaction kettle assembly through a feeding assembly; by arranging the return pipe and the feeding pump, the feeding pump can pump out a medium in the chlorination reactor, then the medium is discharged into the chlorination reactor through the return pipe, and the medium entering the chlorination reactor through the return pipe can impact the medium stored in the chlorination reactor, so that the medium in the chlorination reactor is in a non-static state; therefore, the reaction efficiency of the chlorination reactor is improved.

The invention discloses a production process of aminoacetaldehyde dimethyl acetal, and relates to the field of organic chemical synthesis, and the production process comprises the following steps: (1) ammonification reaction: firstly mixing ammonia water and strong base to form a mixed system, adding a phase transfer catalyst into the mixed system, heating to a preset reaction temperature, slowly dropwise adding chloroacetaldehyde dimethyl acetal, and reacting for 1-2 hours at the temperature of 30-60 DEG C; according to the invention, the phase transfer catalyst is introduced as an acid-binding agent and an accelerant, the reaction temperature is controlled at 30-100 DEG C, and the whole process can be carried out at normal pressure or near normal pressure, so that the dependence of the existing process on high temperature and high pressure is thoroughly abandoned; due to the mild reaction conditions, the requirements for pressure resistance and high temperature resistance of equipment are greatly reduced, the equipment investment and the daily maintenance cost are reduced, and meanwhile, the safety risk in a high-pressure environment is avoided; on the other hand, energy consumption in the production process is remarkably reduced through the low-temperature reaction, the low-carbon chemical development trend is met, and the production cost is reduced for enterprises.

The application discloses a preparation method of 2-methyl-4-chloro-2-butenoic acid ethyl ester, which comprises the following steps: taking an ethoxycarbonyl ethyl triphenyl phosphonium salt aqueous solution and a monochloroacetaldehyde aqueous solution as raw materials, and performing a Wittig reaction under the action of an alkali to obtain 2-methyl-4-chloro-2-butenoic acid ethyl ester, wherein the content of alkali metal ions in the 2-methyl-4-chloro-2-butenoic acid ethyl ester is 1-3 ppm. The method has the advantages of high reaction yield, simple and mild process conditions, moderate residual amount of metal ions in the product, good storage stability of the product and the like.

The invention relates to the technical field of raw materials of skin care products, and particularly discloses a preparation method of a paeonia lactiflora root extract, which comprises the following steps: step 1), putting paeonia lactiflora roots into an extracting solution, and heating and pressurizing for extraction to obtain an extract; step 2), filtering the extract, taking filtrate, and concentrating and drying the filtrate to obtain a Chinese herbaceous peony root extract rich in beta-pentagalloylglucose and oleanolic acid; the extracting solution is a compound of an ethanol water solution, acetic acid, acetone and chloroacetaldehyde. The method has the advantages that more beta-pentagalloylglucose and oleanolic acid are extracted from the paeonia lactiflora roots, so that the whitening and antioxidant effects of the paeonia lactiflora root extract are further improved.

The invention provides a method for preparing 2, 5-dihydroxy-1, 4-dithiane by using a continuous turbulent tubular reactor, and belongs to the technical field of organic synthesis application. In a continuous turbulent tubular reactor, a sodium hydrosulfide aqueous solution and a chloroacetaldehyde aqueous solution are used as raw materials, and 2, 5-dihydroxy-1, 4-dithiane is generated within a short reaction time of dozens of seconds to several minutes. The method has the characteristics of simplicity, convenience and safety in operation and high-yield continuous production of the 2, 5-dihydroxy-1, 4-dithiane product. In addition, the environmental pollution of the process is greatly reduced. And the safety performance is greatly improved.

This invention discloses a fluorescence sensing method and its application for organophosphorus pesticides, belonging to the field of fluorescence sensing technology. The method uses L-cysteine ​​as a reducing agent and ligand to prepare stable copper nanoclusters as fluorescence sensing probes. Under alkaline conditions, the organophosphorus pesticide trichlorfon is readily hydrolyzed to generate dichloroacetaldehyde, which is then directly used as an effective reducing agent to synthesize silver nanoparticles in situ. The silver nanoparticles quench the fluorescence of the copper nanoclusters through an internal filtering effect, achieving specific enzyme-free detection of trichlorfon by detecting changes in fluorescence intensity. Based on this detection method, a portable sensing platform based on a smartphone is constructed to achieve visual detection of trichlorfon. This method effectively overcomes the shortcomings of current trichlorfon fluorescence detection methods, such as poor selectivity, complex detection process, and high detection cost. Compared with other trichlorfon fluorescence sensing methods, this method has the advantages of simple preparation, low cost, and high specificity.

The invention discloses a preparation method of 2-(2, 2-dimethoxyethoxy) ethylamine in the technical field of medicine production, which comprises the following steps: carrying out amino protection reaction on ethanolamine serving as a raw material, then carrying out substitution reaction with chloroacetaldehyde dimethyl acetal, removing a protecting group after the reaction, and obtaining high-purity 2-(2, 2-dimethoxyethoxy) ethylamine through a negative pressure distillation technology. The invention relates to a 2, 2-dimethoxyethoxy) ethylamine product. Through a continuous feeding method, the biggest highlight of the process is that the use of hydrazine hydrate is avoided, and the method has the advantages of safe and simple process and high yield.