A kind of preparation method of efficient and environment-friendly 2-hydroxyethylpyridine

Abstract

The invention discloses a high-efficiency environment-friendly preparation method of 2-hydroxyethylpyridine, which comprises the following steps: proportionally adding 2-methylpyridine and formaldehyde into a high-pressure autoclave, adding a solid superhigh acid catalyst, heating while stirring to react, quickly cooling the high-pressure autoclave, filtering out the solid superhigh acid catalyst, distilling the mixed solution under reduced pressure, and distilling off unreacted 2-methylpyridine, formaldehyde and water under the pressure of 10-100 mmHg to obtain the 2-hydroxyethylpyridine end product. Abundant experiments are performed to screen out the optimal proportion of the reactant raw material to the catalyst thereof; and abundant experiments are performed to screen out the optimum reaction temperature, reaction time and reaction pressure. The whole method has the advantages of reasonable technique, small environmental pollution, low reaction temperature, short reaction time, high reaction efficiency, low production cost, high yield and high purity of the prepared 2-hydroxyethylpyridine.

Description

technical field [0001] The invention belongs to the preparation of pyridine compounds, in particular to a new preparation process of 2-hydroxyethylpyridine. Background technique [0002] 2-Hydroxyethylpyridine is an important chemical raw material, which is widely used in the synthesis and production of organic synthesis and pharmaceutical intermediates. The patent with the publication number CN1580046A provides a process for preparing 2-hydroxyethylpyridine on an industrial scale, using 2-picoline and paraformaldehyde as raw materials, and benzoic acid, chloroacetic acid or acetic acid as a catalyst. The patent with the publication number CN102731372A provides an efficient and environmentally friendly preparation method of 2-hydroxyethylpyridine, using tetrahydrofuran as a solvent, 2-picoline and paraformaldehyde as raw materials, and organic base catalysis. [0003] The above method mainly adopts paraformaldehyde as a reactant, because the decomposition temperature of par...

AI Technical Summary

Problems solved by technology

[0004] Purpose of the invention: the purpose of the present invention is to generally adopt paraformaldehyde as raw material in the preparation technology of existing 2-hydroxyethylpyridine, take liquid acid as catalyzer, have long reaction time, high reaction temperature, large pollution, corrosion Strong and other problems, the present invention provides a novel process for the preparation of 2-hydroxyethylpyridine, through a large number of experimental screening, using solid superacid instead of liquid acid catalyst, less pollution, and can be produced in a shorter reaction time and lower 2-Hydroxyethylpyridine with high purity is prepared at high temperature, the present invention has high yield, strong environmental performance and low production cost