Method for synthesizing alpha-bromoketone and coproducing bromohydrocarbon

Abstract

The invention discloses a method for synthesizing alpha-bromoketone and coproducing bromohydrocarbon. The technical scheme comprises the following steps of: adding arylalkyl ketone compounds, alcohol or epoxy compounds and water into a flask first; dripping bromine into the flask slowly under the conditions of stirring and heating; performing a bromo-reaction on the bromine and the ketone compounds to obtain alpha-bromoketone and bromine hydride; dissolving the bromine hydride in the water to form hydrobromic acid; performing a reaction on the hydrobromic acid and the alcohol or epoxy compounds to obtain bromohydrocarbon ketone compounds; after the reaction is completed, performing steam distillation to obtain a raffinate serving as an alpha-bromoketone crude product after distillation; cooling for separating crystals out; washing and drying the crystals to obtain an alpha-bromoarylalkyl ketone product; separating an aqueous layer from a distillate serving as a bromohydrocarbon crude product; washing an organic layer until the organic layer is neutral; drying by using anhydrous calcium chloride; and distilling to obtain a bromohydrocarbon product. In the method, the water is takenas a solvent, and the bromohydrocarbon is coproduced while the alpha-bromoketone compounds are synthesized; and the gross products of the reaction are the alpha-bromoketone, the bromohydrocarbon and the water, so the method has the characteristics that: the high atom utilization rate of the reaction is high, the generation or the discharging of noxious substances such as bromine hydride gas, strong acid waste water and the like is avoided, and the effects of environmental protection, energy conservation and reduction emission are achieved.

Description

technical field [0001] The invention relates to the field of organic chemical synthesis, in particular to a method for synthesizing α-bromoketone and coproducing brominated hydrocarbons. Background technique [0002] α-Bromoketones 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. Summarizing the research status at home and abroad, it is usually synthesized by α-bromination reaction with different brominating agents in different organic solvents. The focus of these studies was the use of brominating agents, and due attention was not given to the solvents used. So far, the commonly used brominating agents mainly include bromine, copper bromide, solid brominated dioxane, pyridine, hydrobromic acid and bromine 1:1:1 complex, anhydrous aluminum tribromide and bromine A mixture of zinc chl...

AI Technical Summary

Problems solved by technology

[0012] (1). A large number of organic solvents are used. Some of these solvents are highly toxic and pollute the environment seriously; some have a very low boiling point and are extremely volatile, or even cause combustion and explosion. There are great safety problems in industrial production.

(2). In terms of the selection of brominating agent, although the use of copper bromide can avoid the strong irritation of bromine, and the operation is more convenient, it will produce a large amount of by-product brominated ketone, and the utilization rate of bromine is only 50% %; solid brominated dioxane, pyridine, hydrobromic acid and bromine 1: 1: 1 compound etc. are more convenient in bromination, but still need to use bromine and other compounds to prepare in advance; as for quaternary ammonium The perbromide is not only expensive to prepare, but also unsafe to use

[0013] Chinese patent CN101462935A discloses a method for preparing α-bromoketones by using bromate as a brominating agent in the presence of sodium bisulfite. Although this method uses water as a solvent, it will use a large amount of bromate and bisulfite

Chinese patent CN1807382A discloses a method for preparing α-bromoketones by using bromine as the bromination agent and using water as the solvent for bromination. Although water is used as the solvent, the utilization rate of bromine is only 50%, while the other 50 % generates hydrogen bromide, but nothing is done in this patent

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