Method for preparing triclopyr butoxyethyl ester by aqueous phase synthesis method

Abstract

A method for preparing triclopyr butoxyethyl ester by a water phase synthesis method is characterized in that sodium 3,5,6-trichloropyridin-2-olate and chloroacetyl chloride are used as raw materials to generate triclopyr acetyl chloride, then triclopyr acetyl chloride and 2-butoxyethanol react to generate triclopyr butoxyethyl ester, and all reactions are carried out in a water phase. According to the preparation method, the reaction efficiency can be improved, side reactions are reduced, the product purity is improved, and the purity is improved to 98.8%-99.2%; the yield is increased to 99.2%-99.5%; and moreover, the flushing of rainwater to the pesticide can be reduced, and the defect that the triclopyr butoxyethyl ester can take effect without rain within 2 hours after application is overcome.

Description

technical field [0001] The invention relates to a method for preparing triclopyroxyethyl butoxyethyl by an aqueous phase synthesis method, belonging to the technical field of chemical synthesis. Background technique [0002] The pure product of butoxyethyl triclopyr is a fluffy solid with a melting point of 149-150°C and a vapor pressure of 0.168mPa (25°C). It is slightly soluble in water, soluble in ethanol, acetone, etc., and has a solubility of 25°C. : Water 440mg / L, acetone 989g / kg, chloroform 27.3g / kg, hexane 410mg / kg, octanol 307g / kg. [0003] Butoxyethyl triclopyr is an agricultural herbicide, which can be absorbed by the leaves and roots of plants and transferred to the plants, which can control weeds in rice fields and wheat fields, and can also be used in plantations; in pastures, it can control Annual and perennial herbaceous weeds; in forests, it can be used for growth treatment, coniferous tree treatment and weeding in industrial areas. It has the advantages of...

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Problems solved by technology

[0003] Butoxyethyl triclopyr is an agricultural herbicide, which can be absorbed by the leaves and roots of plants and transferred to the plants, which can control weeds in rice fields and wheat fields, and can also be used in plantations; in pastures, it can control Annual and perennial herbaceous weeds; in forests, it can be used for growth treatment, coniferous tree treatment and weeding in industrial areas. It has the advantages of strong drug effect, good mixing and good low temperature resistance; Oxyethyl ester can only be effective if there is no rain within 2 hours of application, and its adsorption capacity to soil is poor

[0005] The above-mentioned preparation method of clopyroxyethyl butoxyethyl still has the following problems: the reaction speed in the organic phase is slow, and the three wastes produced are many, although the water phase synthesis method can be used to reduce the three wastes by reacting in the water phase However, it is difficult to carry out large-scale preparation through the aqueous phase synthesis method, and the problem of stratification is easy to occur during the reaction, resulting in incomplete contact between the reactants and it is difficult to fully react

[0007] Patent CN110204480A discloses a method for preparing triclopyroxyethyl butoxyethyl ester by aqueous phase synthesis method, which includes the following steps: add tetrachloropyridine, sodium hydroxide, water and catalyst to the high-pressure reactor, keep warm for reaction, filter , washed with water, and the filter cake was dried to obtain triclosan sodium; add triclosan sodium, methyl chloroacetate and dimethylformamide to the flask equipped with desiccator, condenser, thermometer and stirrer, and stir Raise the temperature of the reaction system, collect the filter cake and dry it to obtain 2-(3,5,6-trichloro-2-pyridyloxy)methyl acetate; Add 2-(3,5,6-trichloro-2-pyridyloxy) methyl acetate, ethylene glycol monobutyl ether and catalyst, and obtain triclopyroxyethyl butoxyethyl ester after reaction treatment; the patent Insufficient: Stratification is easy to occur in the reaction, resulting in incomplete contact between the reactants, and it is difficult to fully react

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