Preparation method of 3-dimethylamino-1,2-propanediol

Abstract

The invention relates to a preparation method of 3-dimethylamino-1,2-propanediol. The preparation method is characterized in that dimethylamine and 3-chloro-1,2-propanediol are subjected to substitution reaction in a solvent in the presence of alkali to generate 3-dimethylamino-1,2-propanediol; in particular, the alkali is sodium methoxide, and the solvent is a composition of water and methanol. The method comprises the following steps: putting a dimethylamine water solution into a reactor, dropwise adding a methanol solution of 3-chloro-1,2-propanediol at 25 DEG C, simultaneously dropwise adding the remaining methanol solution of 3-chloro-1,2-propanediol and a methanol solution of sodium methoxide when the dropwise adding amount of 3-chloro-1,2-propanediol is 20-30% of the total feeding amount of 3-chloro-1,2-propanediol, after dropwise adding is finished, stirring the solution for 1-3 hours, then heating the solution to 30-40 DEG C, carrying out thermal reaction for 2-4 hours, then heating the solution till reflux, maintaining the solution for 1-3 hours, and finishing reaction. The preparation method has the advantages that the reaction conditions and the reaction processes are comprehensively design; by adopting the method, the purity and yield of the obtained product can be 99.5% and 80% respectively; the preparation method has obvious economic benefits.

Description

technical field [0001] The invention relates to a preparation method of 3-dimethylamino-1,2-propanediol. Background technique [0002] 3-Dimethylamino-1,2-propanediol (DAP) is an important chemical raw material and pharmaceutical intermediate. As a chemical raw material, DAP can be used to produce cationic waterborne polyurethane, degradable fabric softener, anion exchange resin, surfactant and catalyst, etc.; as a pharmaceutical intermediate, DAP can be used to produce anesthetics, anticancer drugs and Antibacterial agents, etc. [0003] The traditional production method of DAP is to add dimethylamine solution, 40% sodium hydroxide solution and 3-chloro-1,2-propanediol into the reactor in sequence, raise the temperature to 50℃~60℃, and stop the reaction for about 4 hours. , to obtain a light yellow liquid, first remove the remaining dimethylamine by normal pressure distillation, then remove water by distillation under reduced pressure, obtain a brownish red liquid after f...

AI Technical Summary

Problems solved by technology

The purity of the product obtained by the traditional method is only about 90% (GC), the content of impurities is high, and the quality is poor, which cannot meet the requirements of pharmaceutical production

In addition, the yield of the traditional method is only about 70%, the yield is low, and the cost is high

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