Preparation method of 2-chloromethyl-3,4-dimethoxypyridine hydrochloride

Abstract

The invention provides a preparation method of 2-chloromethyl-3,4-dimethoxypyridine hydrochloride. The preparation method is characterized in that maltol is used as a raw material, and 2-chloromethyl-3,4-dimethoxypyridine hydrochloride is generated by methylation, ammonification, chlorination, oxidation, methoxy substitution, hydroxymethylation and secondary chlorination reaction in turn. According to the preparation method provided by the invention, synthesis route is simple and clear, and maltol is used as the raw material, thus cost is reduced, and the yield reaches above 75%.

Description

Technical field

[0001] The invention relates to a preparation method of 2-chloromethyl-3,4-dimethoxypyridine hydrochloride, which belongs to the field of medicine manufacturing. Background technique

[0002] 2-Chloromethyl-3,4-dimethoxypyridine hydrochloride is an important intermediate for the synthesis of a new drug pantoprazole. The existing preparation of 2-chloromethyl-3,4-dimethoxypyridine hydrochloride The salt method is generally synthesized with 2-methyl-3-hydroxypyridine as a raw material through a 7-step reaction such as methylation, nitration, and methoxylation. However, such raw materials do not have domestic products and need to be imported and purchased, and the cost will increase. If furan is used as raw material to synthesize by oneself, the yield will be very low, less than 60%, and the purity will be very low. Summary of the invention

[0003] In order to overcome the shortcomings of the prior art, the present invention provides a method for preparing 2-chlorom...