Production process of high-quality trimethyl orthoacetate

Abstract

The invention discloses a production process of high-quality trimethyl orthoacetate. The production process comprises the following steps: performing salification reaction on acetonitrile, methanol and chlorine hydride in the presence of a solvent unsym-trimethyl benzene, so as to obtain ethyleneimine methyl ether hydrochloride; then adding the ethyleneimine methyl ether hydrochloride into a methanol solution; dropwise adding an aminomethanol solution to regulate a pH value, performing alcoholysis reaction to obtain a trimethyl orthoacetate crude product; filtering out solid ammonium chloride, and recycling the solid ammonium chloride; adsorbing filtrate by use of strong-basicity macroporous ion-exchange resin so as to remove chloridion; and finally performing continuous rectification, thereby obtaining a trimethyl orthoacetate product with content greater than 999.5% and yield greater than 85%. The production process is simple in process, the product is stable and reliable, and the used unsym-trimethyl benzene solvent is low in toxicity and safe to use.

Description

Technical field [0001] The invention relates to the field of chemical engineering, in particular to a process for producing high-quality trimethyl orthoacetate. Background technique [0002] Trimethyl orthoacetate is a colorless liquid with a special odor. It is mainly used as a chemical intermediate for the production of medicines and pesticides. In the pharmaceutical industry, it is mainly used to synthesize vitamin B1, vitamin A1, sulfadiazine and other pharmaceutical intermediates; in the agricultural field, it is Intermediate raw materials for the synthesis of cypermethrin, kungfu pyrethroid and other pyrethroids. [0003] At present, the commonly reported production processes of trimethyl orthoacetate are all using acetonitrile, anhydrous methanol and dry hydrogen chloride as raw materials. Under the action of a solvent, a salt-forming reaction is carried out to produce ethyleneimine formamidine hydrochloride, which is then added Methanol is used for alcoholysis to prepare t...

AI Technical Summary

Problems solved by technology

Among them, the choice of solvent has a great influence on the reaction process. Commonly used solvents with low boiling points in industry, such as n-hexane and carbon tetrachloride, are highly toxic and used in large amounts, which is not conducive to saving production costs.

Simultaneously, the residue of chloride ion has influenced the purity of trimethyl orthoacetate in the product