Preparation process of 5-fluoro-2-hydroxyacetophenone

Abstract

The invention relates to the technical field of chemical synthesis, in particular to a preparation process of 5-fluoro-2-hydroxyacetophenone, which comprises the following steps: step 1, preparing 4-acetamido phenol acetate from aminophenol, acetic anhydride and benzene; step 2, adding anhydrous aluminum trichloride, sodium chloride and the 4-acetamido phenol acetate obtained in the step 1 into a stirring device to prepare 2-acetyl-4-acetamido phenol; step 3, refluxing hydrochloric acid and the 2-acetyl-4-acetamido phenol obtained in the step 2, cooling, adjusting the pH value to 6-7, separating out a solid, and drying to prepare 2-acetyl-4-aminobenzene; and step 4, adding the 2-acetyl-4-aminophenol obtained in the step 3 into excessive hydrogen fluoride, so as to prepare the 5-fluoro-2-hydroxyacetophenone. Compared with a two-step reaction in the prior art, the method has the beneficial effects that tedious separation and purification of an intermediate product ester are removed, the reaction time is greatly shortened, the operation is simple and convenient, and the method is suitable for industrial production.

Description

technical field [0001] The invention relates to the technical field, in particular to a preparation process of 5-fluoro-2-hydroxyacetophenone. Background technique [0002] 5-Fluoro-2-hydroxyacetophenone, also known as 2-acetyl-4-fluorophenol, is an important pharmaceutical intermediate, which can be used as a synthetic intermediate for various β receptor blockers, and has broad market prospects. The existing preparation method is to use p-fluorophenol as a raw material, acylate the hydroxyl group, and then use Fries rearrangement to synthesize it. The synthesis of raw materials by this method is expensive, especially the fluorine atom on the aromatic ring is a strong electron-withdrawing group, which may have a great impact on the yield of acylation and rearrangement. The existing preparation method of 5-fluoro-2-hydroxy-acetophenone requires two steps of reaction, and the separation and purification of the intermediate product ester is cumbersome, time-consuming and troub...

AI Technical Summary

Problems solved by technology

Using this method to synthesize raw materials is expensive, especially the fluorine atom on the aromatic ring is a strong electron-withdrawing group, which may have a great impact on the yield of acylation and rearrangement

The existing preparation method of 5-fluoro-2-hydroxy-acetophenone requires two-step reaction, and the separation and purification of the intermediate product ester is cumbersome, time-consuming and troublesome to operate

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