100 results about "Pivaloyl chloride" patented technology

The present invention discloses a new synthesis process of canagliflozin. The new synthesis process comprises: adopting 2-methyl benzoic acid as a starting raw material, and adopting a self-made catalyst, iodic acid and iodine to carry out a reaction to produce an intermediate 1, or adopting 2-methyl benzoic acid as a starting raw material, and adding liquid bromine under effects of a metal reagent and a catalyst to synthesize an intermediate 2; optionally selecting the intermediate 1 or 2 to carry out an acylation reaction with thionyl chloride, and then carrying out a Friedel-Crafts reaction to produce an intermediate 3; adopting ALPHA-D-glucose as a raw material, carrying out a reaction with pivaloyl chloride to protect all hydroxyl, and carrying out a reaction with zinc bromide and bromotrimethylsilane to produce an intermediate 4; linking the intermediate 3 and the intermediate 4 to produce an intermediate 5; and finally under an acid condition, removing the pivaloyl to produce the target compound. The new synthesis process has characteristics of high yield, mild condition, safety, reliability, cheap and easily available raw material, and easy production cost control, and is suitable for industrial production.

The invention belongs to the field of pharmacy and relates to a method for preparing cefazolin compounds. The method comprises the following steps that: 1, cefazolin sodium imidazo (toluene diamine TDA) is synthetized, thiadiazole and 7-ACA are obtained through reaction, dimethyl carbonate is used as solvents in the reaction, boron trifluoride-dimethyl carbonate is used as catalysts, and reagents used for regulating the pH of the reaction liquid are inorganic alkali after the reaction is completed; 2, anhydride is prepared, and the anhydride is obtained through the reaction between tetrazole acetic acid and pivaloyl chloride, and 3, the cefazolin is synthesized, TDA solution reacts with the anhydride, and the reaction solution is subjected to decoloration and purification through an aluminium oxide column.

The invention provides a method for recycling trimethylacetic acid from pivaloyl chloride rectification raffinate. According to the technical scheme, the method has the experiment ideas that components and contents of pivaloyl chloride rectification raffinate are analyzed firstly on the basis of experiment means, on the basis, procedures such as hydrolysis, layering and rectification are confirmedaccording to chemical properties of pivaloyl chloride and trimethylacetic anhydride, and trimethylacetic acid is recycled. Specifically, the method comprises the following steps: firstly, adding a certain amount of pivaloyl chloride rectification raffinate, controlling specific temperature and pressure, adding a proper amount of water for hydrolysis reactions for multiple times to sequentially convert pivaloyl chloride and trimethylacetic anhydride into trimethylacetic acid, leaving to stand to layer water-containing phosphorous acid and a crude trimethylacetic acid product, feeding back thecrude trimethylacetic acid product to a trimethylacetic acid rectification procedure, and performing decoloring refining. By adopting the method provided by the invention, more than 90% of the pivaloyl chloride rectification raffinate can be converted into trimethylacetic acid, so that the utilization rates of raw materials are increased, the wastes are reduced, the environment protection burden of companies is alleviated, and meanwhile the production cost of products is effectively reduced.

The invention discloses a method of tracing places of origin of aquatic products based on amino acid carbon stable isotopes; the method comprises the steps of subjecting a pretreated sample to amino acid extraction before purification; adding hydrochloric acid into the sample, hydrolyzing, centrifuging, subjecting supernate to purification of strong cation exchange columns, concentrating the purified liquid via nitrogen blowing process to obtain sample amino acid; adding amino acids into thionyl chloride-isopropanol solution by means of N-pivaloyl and O-isopropanol ester (NPP) process, performing amino acid derivation, blow-drying by nitrogen, acylating by pivaloyl chloride, passing through silica gel chromatographic columns, concentrating the obtained liquid by a nitrogen blowing process to obtain a derivative, dissolving in ethyl acetate for cryopreservation, and performing amino acid C stable isotope measurement, to be specific, analyzing and identifying an amino acid ester sample via a gas chromatograph-mass spectrometer; comparing amino acid delta 13C values of samples from different sea areas to identify different types of aquatics from different sea areas.

The invention discloses a preparation method for flucloxacillin sodium. The method comprises: (1) adding an initial raw material 1 into dichloromethane, dropwise adding triethylamine, and then dropwise adding pivaloyl chloride for reaction, so as to obtain a mixed anhydride; (2) adding 6-APA into dichloromethane, then adding triethylamine, reacting until the material solution is clear, so as to obtain a 6-APA triethylamine salt solution; dropwise adding the mixed anhydride into the 6-APA triethylamine salt solution for reaction, then distilling at a reduced pressure to remove dichloromethane, so as to obtain an oily substance, then adding acetone into the oily substance, stirring, and filtering off triethylamine hydrochloride, so as to obtain an acetone solution of flucloxacillin triethylamine salt; and (4) adding water and an ethyl acetate solution of sodium 2-ethylhexanoate into the acetone solution of flucloxacillin triethylamine salt, controlling the temperature to be 0-40 DEG C after adding is finished, and crystallizing, so as to obtain flucloxacillin sodium monohydrate. The preparation method has the advantages of mild reaction conditions, high yield, good purity, simple operation, friendliness to environment, and the like.

The invention relates to the field of organic synthesis, in particular to a synthesis method of pinoxaden. The synthesis method comprises the following steps that under catalysis of copper chloride orcuprous chloride, 4-methyl-2,6-diethyl aniline reacts with 1,1-dichloroethylene and nitrous acid ester to generate a compound 1; the compound 1 reacts with sodium alcoholate, and a reaction product is subjected to acidic hydrolysis to obtain a compound 2; the compound 2 reacts with diester carbonate and strong base to obtain an intermediate 3; after diethylene glycol dimethanesulfonate reacts with hydrazine hydrate, salifying with hydrochloric acid is conducted to obtain an intermediate 4; the intermediate 3 and the intermediate 4 are subjected to ring forming under the effect of base to obtain a compound 5; and the compound 5 and pivaloyl chloride react under the effect of the base or base / DMAP to obtain the pinoxaden. The synthesis method of the pinoxaden does not use expensive or toxiccatalysts, does not need to adopt a protection / deprotection strategy, and has the characteristics of low cost and high atomic economy.

The invention discloses a synthetic method of cefadroxil. The synthetic method of cefadroxil comprises the following steps of: dissolving 7-aminodesacetoxycephalosporanic acid by adopting organic base at the temperature ranging from minus 10 DEG C to minus 50 DEG C to obtain 7-aminodesacetoxycephalosporanate; carrying out reaction on HPCDane salt and pivaloyl chloride at the temperature ranging from minus 20 DEG C to minus 70 DEG C to generate mixed anhydride and carrying out condensation reaction on the mixed anhydride and 7-aminodesacetoxycephalosporanate, extracting and regulating pH value of a water layer, then separating salt and regulating pH value, and crystallizing to obtain cefadroxil. By adopting the manner, the synthetic method of cefadroxil has the advantages that a process is simple, solvate does not need to be formed in a synthetic process, crystallization can be directly carried out in water, consumption of an organic solvent is reduced, production cost is reduced, yield of cefadroxil is high, various quality indexes are qualified, pharmacopeia standards are met, and implementation of industrial production can be facilitated.

The invention relates to a method and a device for continuously preparing pivaloyl chloride. The specific operation method comprises the following steps: adding raw materials pivalic acid and phosphorus trichloride to a raw material mixer respectively, uniformly stirring the raw materials, and then conveying the raw materials into a microchannel reactor with a solid catalyst to prepare a chlorination solution; feeding the prepared chlorination solution into two chromatography tanks for chromatography respectively to prepare a crude product of pivaloyl chloride; finally, feeding the crude product of pivaloyl chloride into a rectification section to obtain a pure product of pivaloyl chloride. The microchannel reactor is adopted to replace an original chlorination reactor, so that the reaction is more thorough, the conversion rate is high, and purity is high; a continuous reaction is adopted to replace the original intermittent reaction, and reaction time is greatly shortened to 0.5 hoursfrom 12 hours in the prior art.

The invention belongs to the technical field of chemical synthesis, and particularly relates to a method and device for continuously preparing chloropivaloyl chloride by using a micro-channel. The method comprises the steps: mixing pivaloyl chloride and chlorine, then adding the mixture to a preprocessor with a composite photocatalyst attached to the inner wall, pretreating, allowing the pretreated mixture to enter a micro-channel photochlorination reactor, carrying out a photochlorination reaction under an ultraviolet irradiation condition to prepare a chloropivaloyl chloride reaction solution, and rectifying the chloropivaloyl chloride reaction solution to obtain the chloropivaloyl chloride finished product. The inner wall of the preprocessor is lined with a nano MnS-ZnS composite photocatalyst to enhance the photochlorination reaction efficiency; the multi-wave band ultraviolet lamp adopts a surrounding mode, so that the harm of light diffusion to the surrounding environment is reduced while the utilization efficiency of ultraviolet light is enhanced; by adopting the micro-channel photochlorination reactor, the reaction time is shorter, the reaction is more thorough, and the impurities are fewer; a middle distillation tower is added in the rectification section, so that middle distillation impurities are separated more thoroughly, and the product quality is higher.