Method for synthesizing alpha-brominated aromatic ketones compound

Abstract

The invention discloses a method for synthesizing an alpha-brominated aromatic ketones compound. The method comprises the following steps: taking an aromatic ketones compound as a substrate, hydrogen bromide as a brominating agent, copper nitrate as a catalyst, oxygen or air as an oxidizing agent and water as a solvent; performing brominating reaction at 25-100 DEG C; and after finishing the reaction, post-processing the reaction solution, thereby obtaining the alpha-brominated aromatic ketones compound. According to the method, water is taken as the solvent, so that the pollution and harm to the environment during a producing, recycling or discharging process caused by an organic solvent are avoided; the method is an environment-friendly green synthesizing technology; the hydrogen bromide is taken as the brominating agent, so that the operation is conveniently and easily controlled, the final reaction products are only alpha-bromoketone and water, no other harmful matter is generated and the defects of the prior art are eliminated; the oxygen or air is taken as the oxidizing agent, so that the price is low and the oxidizing agent is easily obtained; and the method provided by the invention is characterized by convenience in operation, safety, environmental protection, low cost, high economic benefit, and the like, and belongs to a green chemical technology.

Description

(1) Technical field [0001] The invention relates to a method for synthesizing aromatic ketones, in particular to a method for synthesizing α-bromoaromatic ketones. (2) Background technology [0002] α-Bromoaryl ketones are very important chemical intermediates for the synthesis of various medicines, pesticides, and dyes. With the continuous expansion of their application fields, people pay more and more attention to the research on their synthesis methods. [0003] The preparation of α-bromoaryl ketones usually requires bromine to be added to the organic solution of aromatic ketones, and the reaction generates hydrogen bromide in an equimolar amount with the bromine participating in the reaction. The bromine of this method The atomic utilization rate is only 50%, resulting in waste of bromine. At the same time, the commonly used solvents in the reaction include acetic acid, diethyl ether, dioxane, chloroform, dichloroethane, ethyl acetate, benzene, etc., which pollute the e...

AI Technical Summary

Problems solved by technology

[0004] Because liquid bromine is volatile and has a strong irritant and corrosive effect, it is unsafe to operate and seriously affects the environment. Therefore, in recent years, various new bromination agents have been proposed, such as: copper bromide, dioxane or pyridine / Hydrobromic acid / bromine 1:1:1 complex, mixture of anhydrous aluminum tribromide and zinc bromide, quaternary ammonium perbromide, bromosuccinimide, bromochloroform, etc.

Although the use of copper bromide can avoid irritation, it increases the production burden and increases the production cost; although the 1:1:1 complex of brominated dioxane, pyridine, hydrobromic acid and bromine, etc. is more convenient in bromination , but still need to use bromine and other compounds for pre-preparation, not only did not reduce the cost, but also increased the process; the perbromide of the quaternary ammonium salt has higher cost and similar unfavorable factors as above

[0005] In order to better save costs, reduce pollution, improve the utilization rate of bromine and reduce the consumption of organic solvents, people have carried out a lot of useful discussions, such as: Chinese patent CN101462935A discloses a kind of use of bromate as brominating agent in sub- In the presence of sodium bisulfate, bromination is carried out to prepare α-bromoaromatic ketones. Although this method uses water as a solvent, it will use a large amount of bromate and bisulfite; Chinese patent CN1807382A discloses a Using bromine as the bromination agent and water as the solvent to carry out bromination to prepare α-bromoaromatic ketones, although water is used as the solvent, bromine is still used as the bromination agent, and the bromination produced in the patent Hydrogen has not been further utilized; China CN101928208A discloses a method for brominating α-brominated aromatic ketones using hydrobromic acid as a brominating agent in the presence of hydrogen peroxide. This method uses water as a solvent and hydrogen peroxide as a The oxidizing agent carries out the bromination reaction of α-bromoaromatic ketones, and the products are α-bromoaromatic ketones and water. The atom of bromine is economical, which reduces pollution and production costs, but the use of hydrogen peroxide still requires a high cost, and is prone to decomposition at high temperatures, which reduces the availability of oxidants

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