36results about How to "Reasonable choice of reaction process" patented technology

The invention relates to an industrial method for preparing 3- amino- 2, 2- bimethyl propionamide, which is a segment in high pressure protein proenzyme inhibitor. The invention takes normal and cheapcyanoacetamide as raw material, alkalyating two nethyls, catalytic hydrogenating or adding reducant agent and getting 3- amnio- 2, 2- bimethyl propionamide. The chenmical reaction is shown in the graph. The invention solves problems of difficulty of getting raw material, low productivity and long process line, needs no column chromatography and purification, avoids toxic potassium cyanide and realizes large scale production.

The invention relates to a synthetic method for trandolapril key intermediate (2S, 3aR and 7as)-octahydro-1H-indole-2-carboxylic acid. The method comprises the following steps: obtaining a pair of cis 1, 2-cyclohexane dimethyl acid mono-methyl ester after refluxing hexahydrophthalic anhydride by methanol, splitting the cis 1, 2-cyclohexane dimethyl acid mono-methyl ester by (-) N, N-dimethyl amino diol to obtain 1, 2-cyclohexane dimethyl acid mono-methyl ester of (1R, cis) and (1S, cis) respectively; refluxing (1R, cis)-1, 2-cyclohexane dimethyl acid mono-methyl ester obtained by reclaiming mother liquor in hydrochloric acid to obtain cyclohexane o-dioctyl phthalate, and cyclizing the cyclohexane o-dioctyl phthalate to obtain an initial raw material of the hexahydrophthalic anhydride; and circulating the processes unceasingly to improve the impurity of the (1R, cis)-1, 2-cyclohexane dimethyl acid mono-methyl ester, and then directly entering a follow-up synthesizing process. The process effectively solves the problems of treatment of (1S, cis) 1, 2-cyclohexane dimethyl acid mono-methyl ester after racemization of (d1)1, 2-cyclohexane dimethyl acid mono-methyl ester and yield of (1R, cis)-1, 2-cyclohexane dimethyl acid mono-methyl ester, improves utilization efficiency of raw materials, reduces cost of products, is more suitable for industrialized production, can effectively improve follow-up reaction efficiency, and saves energy of a system.

An industrial process for preparing 2-chloro-5-fluoro-nicotinic acid from 2,6-dichloro-5-fluoro-nicotinic acid includes catalytic hydrogenating, nitroxidizing and chlorinating. Its advantages are high outpt rate, and short process.

Production of 2-chlorine-5-fluorine-nicotinate and acid is carried out by 2-chlorine-5-fluorine-nicotinate and related carboxylic acid selective dechlorinating, and 2-chlorine-5-fluorine-nicotinate hydrolyzing 2-chlorine-5-fluorine-niacin under the exist of alkaline substances. It can be used for 2-chlorine-5-fluorine-nicotinate and 2-chlorine-5-fluorine-niacin medicine intermediate.

The present invention relates to industrial preparation process of N-tert-butoxy carbonyl-5-aza-2-oxa-3-one-dicyclo-[2, 2, 1] heptane in one kettle. The present invention prepares N-tert-butoxy carbonyl-5-aza-2-oxa-3-one-dicyclo-[2, 2, 1] heptane with facile L-hydroxy praline as material, and through methyl esterification, tert-butoxy carbonyl radical protection, paratoluene sulfonation, hydrolysis and lactonization. The present invention has lowered cost, raised yield, less environmental pollution and no need of column chromatographic purification, and may be used in industrial production.

This invention relates to a process for synthesizing optically active omega-aryl-(2S)-N-tert-butyloxycarbonyl-alpha-amino acid derivative, more specifically, omega-aryl-(2S)-N-tert-butyloxycarbonyl-alpha-amino acid ester. The process comprises: preparing omega-arylalkyl bromide into Grignard reagent, reacting with ethyl N-tert-butyloxycarbonyl-L-pyroglutamate to obtain omega-aryl-5-one-(S)-N-tert-butyloxycarbonyl-alpha-amino acid ethyl ester, and reducing to obtain omega-aryl-(2S)-N-tert-butyloxycarbonyl-alpha-amino acid ethyl ester. The process has such advantages as reasonable reaction process, abundant raw materials, short synthesis time, and no need for expensive enzyme reagents, and is suitable for mass production.

The process of preparing 4, 7-diazaindole includes the following steps: 1. reaction of amino-3-methyl pyrazine and pivaloyl chloride or Boc anhydride to obtain 2-pivaloyl amino-3-methyl pyrazine or 2-tert-butyloxyformamido-3-methyl pyrazine; 2. reaction of the obtained 2-pivaloyl amino-3-methyl pyrazine or 2-tert-butyloxyformamido-3-methyl pyrazine with R2Li and HCOR3 to produce aldehyde intermediate; and 3. eliminating the protecting ring of the intermediate to obtain 4, 7-diazaindole. The present invention is one effective process of synthesizing 4, 7-diazaindole as one medicine intermediate.

The invention relates to a method for preparing 3-aza-bicyclo[4.1.0]heptane-6-formic acid with a protective group, and mainly solves the technical problem that multi-step chromatographic purification is needed in the conventional process for preparing the 3-aza-bicyclo[4.1.0]heptane-6-formic acid. The method comprises the following steps of: performing reflux alkylation reaction on conventional and readily available ethyl isonicotinate serving as a raw material and halohydrocarbon in alcohol solution to obtain quaternary ammonium; performing cyanoborohydride reaction to obtain amino-protected 1,2,3,6-tetrahydropyridine-4-ethyl formate; not performing purification, and directly performing ring-closing reaction to obtain a three-membered ring; and performing alkaline hydrolysis reaction to obtain amino-protected 3-aza-bicyclo[4.1.0]heptane-6-formic acid. The 3-aza-bicyclo[4.1.0]heptane-6-formic acid with the protective group is an important medicinal intermediate.

The present invention relates to continuous industrial preparation process of N-tert-butoxy carbonyl-5-aza-2-oxa-3-one-dicyclo-[2, 2, 1] heptane. The present invention prepares N-tert-butoxy carbonyl-5-aza-2-oxa-3-one-dicyclo-[2, 2, 1] heptane with facile L-hydroxy praline as material, and through methyl esterification, tert-butoxy carbonyl radical protection, paratoluene sulfonation, hydrolysis and lactonization. The present invention has lowered cost, raised yield, less environmental pollution and no need of column chromatographic purification, and may be used in industrial production.