Synthesis method of alpha-acetyl-gamma-butyrolactone

Abstract

The invention relates to the technical field of chemical synthesis, and discloses a synthesis method of alpha-acetyl-gamma-butyrolactone. The method comprises: carrying out inert gas replacement on afirst reaction kettle, adding metal sodium in the inert gas atmosphere, and raising the temperature until the metal sodium is molten in order to obtain molten metal sodium; adding gamma-butyrolactoneand acetate into a second reaction kettle, raising the temperature until the system is refluxed, dropwise adding molten liquid metal sodium into the system, carrying out a condensation reaction, and keeping the system refluxed for 1-16 h after the drop-by-drop addition of the liquid metal sodium is finished; and neutralizing the system with an acid solution after the condensation reaction is finished, carrying out phase splitting, and carrying out distillation and reduced pressure rectification on the obtained organic phase to obtain the alpha-acetyl-gamma-butyrolactone. A solvent-free technology is adopted, and the reaction process is controlled by controlling the dropping speed of the liquid metal sodium, so the method has the characteristics of stable and safe reaction, and avoiding ofthe problems of environmental pollution and difficult separation caused by using benzene substances as a solvent and an extractant in the traditional process.

Description

technical field [0001] The invention relates to the technical field of chemical synthesis, in particular to a synthesis method of α-acetyl-γ-butyrolactone. Background technique [0002] α-acetyl-γ-butyrolactone is an important pharmaceutical intermediate and organic chemical raw material. It is an important intermediate for the preparation of vitamins and chlorophyll. Pharmaceutical intermediates of drugs such as thiazole, Yanxintong and chloroquine. At present, there are mainly two routes for the preparation of α-acetyl-γ-butyrolactone. One is a process based on ethylene oxide and ethyl acetoacetate as starting materials, and the other is based on γ-butyrolactone. and acetate as the starting material. [0003] Wherein, Chinese patent application documents (publication number: CN 1357545 A), U.S. Patent US 2443827, British Patent GB 740993 and Japanese Patent JP 4212662 etc. all disclose similar synthesis of starting materials with ethylene oxide and ethyl acetoacetate Pr...

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Problems solved by technology

However, rapid cooling of the molten sodium metal to 50-60°C is easy to agglomerate, which is difficult to implement in industrial production, and also uses a chlorinated solvent, which causes great environmental pollution.

[0008] In addition, the Chinese patent application document (publication number: CN 101092407 A) discloses the synthesis of α-acetyl-γ-butyrolactone through the acylation reaction of ethyl acetate and γ-butyrolactone through the gas phase catalysis of fluorine alkali solid-phase catalyst, although It solves the safety hazard, but due to the large energy consumption, the cost is too high, and the use of solid alkali fluoride as a catalyst has certain hidden dangers to products and environmental pollution, and has not been put into actual production and life at present.

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