Method for synthesizing ethyl 4,4-difluoroacetoacetate in catalyzed mode through layered materials

Abstract

The invention discloses a method for synthesizing ethyl 4,4-difluoroacetoacetate in a catalyzed mode through layered materials. The method includes the following steps: 1, a divalent and trivalent metal salt solution and a sodium hydroxide and sodium carbonate mixed solution are rapidly mixed to prepare multielement hydrotalcite, the multielement hydrotalcite is roasted to be added into a fluoride-salt saturation aqueous solution, the mixture is stirred, filtered, washed and dried to be roasted under the nitrogen condition, and catalysts are obtained; 2, ethyl acetate, ethyl difluoroacetate and the catalysts are added into a four-opening flask, an ethyl alcohol and ethyl acetate mixture is evaporated after temperature rising, stirring and reacting are carried out, cooling is carried out, catalysts are filtered and recycled, filtrate is acidized, cooled and filtered, and pressure reduction rectification is carried out on the filtrate to obtain the ethyl 4,4-difluoroacetoacetate; 3, the recycled catalysts are sufficiently washed through solvents and roasted to be added into a fluoride-salt saturation aqueous solution, the mixture is stirred, filtered, washed and dried to be roasted under the nitrogen condition, and the catalysts are regenerated. The method has the advantages that the yield is high, the catalysts can be recycled, and the method is safe and environmentally friendly.

Description

technical field [0001] The invention relates to a method for synthesizing ethyl difluoroacetoacetate, and in particular provides a method for catalytically synthesizing ethyl difluoroacetoacetate with a layered material. Background technique [0002] Due to the characteristics of fluorine atoms (high electronegativity and small atomic radius) and electronic effects, penetration effects, hindrance effects and simulation effects, the introduction of fluorine atoms or fluorine-containing groups into organic molecules will affect the physical and chemical properties of organic molecules , especially have a great impact on physiological properties. [0003] Compounds containing fluoromethyl groups are widely used in the fields of pesticides, medicines, and materials, because their electrical and analog effects change the density of electron distribution inside the molecule and destroy the acid-base ratio of the internal structure of the compound, thereby changing the physiologica...

AI Technical Summary

Problems solved by technology

Claisen condensation often uses a strong base as a catalyst, such as metal sodium, sodium ethoxide or sodium hydride, etc. If metal sodium is used directly, the reaction will be violent and hydrogen will be generated, which is very dangerous; sodium hydride is highly active and will also A large amount of hydrogen is produced, so the risk is also high; if sodium ethoxide is used, in addition to the consumption of stoichiometric sodium ethoxide, a large amount of ethanol will be generated, which will affect the condensation yield and the separation of products; the above catalyst also has the problem that the catalyst cannot be recovered. , high production cost