Industrial preparation method of 5-methylpyrazin-2-amine

Abstract

The invention relates to an industrial preparation method of 5-methylpyrazin-2-amine. In the invention, the 5-methylpyrazin-2-amine is prepared from general and easily obtained 5-methyl-2-pyrazinecarboxylic acid by the steps of azidation, Curtius rearrangement and Boc desorption. The chemical reaction formula is shown in the specification. The invention solves the problems of high cost, low yield, environment pollution and the like in the prior art, does not need column chromatography for purification, and can realize large-scale industrial production.

Description

Technical field: The invention relates to a preparation method of a 2-aminopyrazine drug intermediate, in particular to an industrial preparation method of 2-amino-5-methylpyrazine. Background technique: 2-Aminopyrazine compounds are relatively important drug intermediates, so the synthesis of such compounds has important application value. The 2-amino-5-methylpyrazine sold in the market is expensive, and there is still no industrial synthesis method for effectively preparing this product so far. The method for preparing 2-amino-5-methylpyrazine mainly contains following two kinds at present: method one, see literature synthetic route 1, take 5-methylpyrazine formic acid as raw material, first react with oxalyl chloride to obtain compound 6, then React with sodium azide to generate compound 7, then react with benzyl alcohol in situ to obtain Cbz-protected intermediate 8 through Curtius rearrangement, and finally obtain target compound 3 through Pd / C hydrogenation (Patent: ...

AI Technical Summary

Problems solved by technology

The technical problem to be solved in the present invention is: solve the problem that the reaction conditions in the existing 2-amino-5-methylpyrazine preparation process are harsh and cannot be produced on a large scale; The industrialized preparation method of 2-amino-5-methylpyrazine

Images