Method for preparing fluacrypyrim

Abstract

The invention discloses a method for preparing fluacrypyrim. The method comprises the following steps: firstly, etherification reaction: taking (E)-2-(2'-chloromethyl) phenyl-methyl 3-methoxyacrylateand 2-isopropoxy-4-hydroxy-6-trifluoromethyl pyrimidine as raw materials, adding the raw materials into a solvent DMF and adding K2CO3 as an acid-binding agent at the same time; carrying out a reaction at 120 to 150 DEG C, ending the reaction until the (E)-2-(2'-chloromethyl) phenyl-methyl 3-methoxyacrylate disappears to obtain feed liquid and cooling the feed liquid to room temperature; secondly,extraction of crude products: adding the cooled feed liquid into an alkali aqueous solution and stirring to obtain a viscous material; then extracting, washing, drying and concentrating to be dry toobtain a crude product of the fluacrypyrim; thirdly, refining: recrystallizing the crude product of the fluacrypyrim, thus obtaining a fluacrypyrim product with the purity of not less than 96 percent.The method disclosed by the invention has the advantages of high industrial feasibility, higher yield, more stable quality, lower cost, high safety and environment friendliness.

Description

technical field [0001] The invention belongs to the field of synthesis of the acaricide pyrimaben, in particular to a method for preparing pyrimaben. Background technique [0002] Pyrimiden is the first methoxyacrylate acaricide developed by BASF and Soda Corporation of Japan. The principle of insecticide is mainly to inhibit the mitochondrial respiration of insects and cause the death of insects. It is mainly used to control citrus. Mites of various fruits such as apples. At present, there are few types of effective acaricides in China, and the synthesis process of pyrimidaben is still in the stage of laboratory research and development in China. Synthesis and acaricidal activity of esters. "Pesticides", Volume 48, No. 3, March 2009.) It does not yet have the possibility of industrial production. [0003] The synthetic route that comparative literature adopts is as follows: [0004] [0005] The response is an SN 2 The reaction mechanism is that 2-isopropoxy-4-hydrox...

AI Technical Summary

Problems solved by technology

This side reaction means that one equivalent of methyl ester will be hydrolyzed for every equivalent of pyrimidin, resulting in the loss of methyl ester raw material, and the hydrolyzed product is difficult to remove through post-treatment operations, and the product needs to be separated by column

The technical level that can be achieved in the comparative literature can only stay within 100g, and the target product needs to be obtained through column separation. The column separation method uses a large amount of organic solvents, and the obtained products are also very few, and the capacity of the chromatographic column is limited. The cost of purification is very high. Purification of 0.5g of crude pyrimaben requires 200g of silica gel and at least 2kg of organic solvent. In addition, the separation process of filling the column takes more than 3 days, and the organic solvent is difficult to recycle and reuse. It is easy to cause pollution to the environment and is expensive. , difficult to adapt to industrial production

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