Synthesis method of halogen acetone

Abstract

The invention discloses a synthesis method of halogen acetone. The method comprises the following steps of: selecting a reactive rectification device, wherein the height ratio of the reaction section to the rectification section of the reactive rectification device is 1:3-1:6; adding 0.1 to 2 equivalent water to the bottom of the reactive rectification device, heating the water to the temperature of between 95 and 100 DEG C, and adding halogenated ethyl acetoacetate to the middle part of the reaction section, wherein the molar ratio of the halogenated ethyl acetoacetate to the water is 1:1-1:2.5; and filling strongly acidic cation exchange resin serving as a catalyst into the reaction section, reacting the halogenated ethyl acetoacetate and water vapor after the halogenated ethyl acetoacetate is catalyzed at the reaction section, performing separation at the rectification section, collecting the halogen acetone product at the top of the rectification section, and putting a product collecting bottle in a freezing bath of 10 DEG C below zero to 60 DEG C below zero, wherein the purity of the collected product is more than 99 percent. Because the reactive rectification device is used for continuously producing the halogen acetone, the method has the advantages of high selectivity, high conversion rate, high production capacity, high product purity, simplicity and convenience in operation and low energy consumption; the reagent is easily obtained; the adopted catalyst can be reused; and the method is clean, environmentally-friendly, safe and reliable.

Description

technical field [0001] The present invention relates to a compound synthesis method, in particular to a synthesis method of halogenated acetone. Background technique [0002] Halogenated acetones, especially fluorinated acetones, are important pharmaceutical synthesis intermediates. It can participate in a variety of organic synthesis reactions, especially in the synthesis of fluorine-containing medicines, pesticides and dyes, and is one of the important intermediates of fluorine-containing fine chemicals. [0003] There are now methods for synthesizing related halogenated acetones, as follows: [0004] Masanori Tsukamoto, Saitama et al. (US6774266) used 3-halo-1,1,1,3-tetrafluoroacetone as a raw material for a gas phase reduction reaction. Using metal palladium as a catalyst, the raw materials are vaporized with hydrogen and passed through the catalyst palladium to react to generate trifluoroacetone. The reaction formula is as follows (Ⅱ): [0005] [0006] The disa...

AI Technical Summary

Problems solved by technology

[0015] The disadvantage of this synthesis method is that the raw materials are not easy to obtain, and the cost is high; trifluoroacetic acid is strong in acidity, and there is a certain danger in the production operation.

[0016] To sum up, these reactions or some auxiliary catalysts, raw materials have higher market prices, resulting in higher synthesis costs; or some reaction conditions are relatively harsh; therefore, we have innovated a new and more ideal synthesis method

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