Method for preparing ethyl trans-4-amino-cyclohexanecarboxylate hydrochloride

A technology of ethyl cyclohexanecarboxylate hydrochloride and cyclohexanedicarboxylic acid, which is applied in the preparation of carbamic acid derivatives, the preparation of carboxylate, and the preparation of carboxylate/lactone, etc. Low, corroded equipment and other problems, to achieve the effect of solving the problem of magnified risk, easy operation and short production cycle

Inactive Publication Date: 2019-01-29
CHENGDU BAISHIXING SCI & TECH IND
View PDF5 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] In order to solve the process scheme of the raw material trans-4-aminocyclohexanecarboxylic acid prepared by the above-mentioned prior art to prepare trans-4-aminocyclohexanecarboxylic acid ethyl ester hydrochloride, there are high temperature and high pressure reactions, use of highly toxic organic solvents, complex operations, and high efficiency. Low, corroded equipment, defects that do not meet the requirements of environmental protection, the present invention provides a method for avoiding the need to use trans-4-aminocyclohexanecarboxylic acid to prepare trans-4-aminocyclohexanecarboxylic acid ethyl ester hydrochloride

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for preparing ethyl trans-4-amino-cyclohexanecarboxylate hydrochloride
  • Method for preparing ethyl trans-4-amino-cyclohexanecarboxylate hydrochloride
  • Method for preparing ethyl trans-4-amino-cyclohexanecarboxylate hydrochloride

Examples

Experimental program
Comparison scheme
Effect test

experiment example 1

[0033] S1: Add 2.4 liters of ethanol and 400 grams of trans-1,4-cyclohexanedicarboxylic acid into a 5-liter round-bottomed flask, stir and mix thoroughly, then add 12 milliliters of concentrated sulfuric acid, heat up to reflux state and react for about 20 hours, point Plate detection raw material reaction is complete, cooled down to room temperature, concentrated, dissolved with 500 ml of ethyl acetate, washed to neutral, dried and concentrated to obtain 531 g of diethyl trans-1,4-cyclohexanedicarboxylate as light yellow Oily liquid, yield 100%;

[0034] S2: In a 5-liter three-necked round-bottomed flask, dissolve 530 grams of the light yellow oily liquid obtained in the previous step in 3 liters of a mixed solvent of anhydrous toluene and absolute ethanol (volume ratio 1:2), and stir under room temperature. Add 93 grams of sodium hydroxide in absolute ethanol to obtain a white suspension, continue to stir until the pH value does not change, point the plate to detect that the...

experiment example 2

[0038] S1: Add 2.5 liters of ethanol and 450 grams of trans-1,4-cyclohexanedicarboxylic acid into a 5-liter round-bottomed flask, stir and mix thoroughly, then add 10 milliliters of concentrated sulfuric acid, heat up to reflux state and react for about 20 hours, point Plate detection raw material reaction is complete, cooled down to room temperature, concentrated, dissolved with 500 ml of ethyl acetate, washed with water until neutral, dried and concentrated to obtain 596 g of trans-1,4-diethyl cyclohexanedicarboxylate as light yellow Oily liquid, yield 100%;

[0039] S2: In a 5-liter three-necked round-bottomed flask, dissolve 596 grams of the light yellow oily liquid obtained in the previous step in a mixed solvent of 3.1 liters of anhydrous toluene and absolute ethanol (volume ratio 1:3), and drop under stirring at room temperature Add 104 grams of sodium hydroxide in absolute ethanol to obtain a white suspension, continue to stir until the pH no longer changes, point the ...

experiment example 3

[0043] S1: Add 10 liters of ethanol and 1720 grams of trans-1,4-cyclohexanedicarboxylic acid into a 20 liters reactor, stir and mix thoroughly, and then add 100 milliliters of concentrated sulfuric acid. Raise the temperature to a reflux state and react for about 20 hours. The reaction of the raw materials is detected by pointing a plate, and the reaction is cooled down to room temperature. Concentrate, dissolve with 5 liters of ethyl acetate, wash with water until neutral, dry and concentrate to obtain 2280 g of diethyl trans-1,4-cyclohexanedicarboxylate as light yellow oily liquid with a yield of 100%.

[0044] S2: In a 20-liter reactor, dissolve 2280 grams of the light yellow oily liquid obtained in the previous step in a mixed solvent of 15 liters of anhydrous toluene and absolute ethanol (volume ratio 1:1), and add 400 grams of it dropwise under stirring at room temperature Anhydrous ethanol solution of sodium hydroxide, to obtain a white suspension, continue to stir unti...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a method for preparing ethyl trans-4-amino-cyclohexanecarboxylate hydrochloride, and belongs to the field of organic chemistry. Trans-1,4--cyclohexanedicarboxylic acid is usedas an initial material and reacts with anhydrous ethanol to produce intermediate diester A under the condition of a sulfuric acid catalyst, monoester is hydrolyzed by intermediate diester A to obtainintermediate monoacid B, the intermediate monoacid B and DPPA are subjected to Curtius rearrangement to obtain intermediate C, the intermediate C is deprotected by hydrogen chloride ethyl acetate solution to obtain final product ethyl trans-4-amino-cyclohexanecarboxylate hydrochloride I. The process adopted by the invention has the advantages of short reaction steps, cheap raw materials, mild reaction conditions and high yield, and is suitable for industrialized large-scale production.

Description

technical field [0001] The invention belongs to the field of organic chemistry, and in particular relates to a preparation method of trans-4-amino-ethyl cyclohexanecarboxylate hydrochloride, an active drug intermediate. Background technique [0002] There are two stereoisomers of 4-aminocyclohexanecarboxylic acid: cis-4-aminocyclohexanecarboxylic acid and trans-4-aminocyclohexanecarboxylic acid, where the trans isomer is more present than the cis isomer The more unique activity and characteristics have attracted widespread attention as a pharmaceutical intermediate, attracting people to increase the process development of this product. Trans-4-aminocyclohexylcarboxylic acid (ACCA) and its derivatives are one of the important pharmaceutical intermediates, mainly used to synthesize short peptides, polypeptides, isoquinuclidone and other drugs. Ethyl trans-4-aminocyclohexylcarboxylate hydrochloride is a derivative of ACCA and is one of the important building blocks for constru...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C07C227/20C07C229/48
CPCC07C51/09C07C67/08C07C227/20C07C269/00C07C2601/14C07C229/48C07C271/24C07C69/75Y02P20/55
Inventor 石常青
Owner CHENGDU BAISHIXING SCI & TECH IND
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap