Method for producing 2, 6-diethyl-N-(2-propoxyethyl)phenylamine serving as pretilachlor intermediate

Abstract

The invention discloses a method for producing 2,6-diethyl-N-(2-propoxyethyl)phenylamine serving as a pretilachlor intermediate. The method is characterized by comprising the step of enabling 2,6-diethylphenylamine, chloroethyl propyl ether and an acid binding agent to react at normal pressure or under a pressurization condition to generate the 2,6-diethyl-N-(2-propoxyethyl)phenylamine, wherein the molar ratio of the 2,6-diethylphenylamine to the chloroethyl propyl ether to the acid binding agent is (1.5-2.5) to 1 to (0.45-0.7), the alkylation reaction temperature ranges from 120 DEG C to 180 DEG C, and the reaction lasts for 5-8 hours. According to the method, the novel acid binding agent reacts with the 2,6-diethylphenylamine and chloroethyl propyl ether to generate the 2,6-diethyl-N-(2-propoxyethyl)phenylamine; and compared with an existing alkylation method, the method not only has the characteristic of short process flow, but also has the advantages that the utilization rate of raw materials is increased, the production cost is reduced, and the better industrial value is achieved.

Description

technical field [0001] The invention relates to the field of herbicides, in particular to a method for producing pretilachlor intermediate 2,6-diethyl-N-(2-propoxyethyl)aniline. Background technique [0002] Pretilachlor belongs to 2-chlorinated acetanilide herbicides. It is a high-efficiency, low-toxicity, special-purpose herbicide for rice fields at bud stage. It can control weeds such as barnyard grass and cattle felt in rice fields, and is widely used. At present, the most common production method of pretilachlor is to use 2,6-diethylaniline as the starting material, and obtain 2,6-diethyl-N-(2-propoxyl Ethyl) aniline, and then acylation reaction with chloroacetyl chloride. The key is the monoalkylation reaction in the first step. If 2,6-diethylaniline reacts with chloroethyl propyl ether, etc., there will be more dialkylated products. In order to reduce the amount of dialkylated products, usually Adopt the method of excessive 2,6-diethylaniline, can be accompanied by ...

AI Technical Summary

Problems solved by technology

The key is the monoalkylation reaction in the first step. If 2,6-diethylaniline reacts with chloroethyl propyl ether, etc., there will be more dialkylated products. In order to reduce the amount of dialkylated products, usually Adopt the method of excess 2,6-diethylaniline, so that the product will be accompanied by excessive raw materials, resulting in the situation of low efficiency of subsequent rectification and high manufacturing cost

[0003] 2,6-diethyl-N-(2-propoxyethyl)aniline is the key intermediate for the synthesis of pretilachlor, and the traditional synthetic methods include: one, 2,6-diethylaniline and ethylene glycol Monopropyl ether reacts under high temperature and high pressure, catalyzed by a noble metal complex catalyst and in a hydrogen atmosphere. This method still has problems in large-scale use

At present, most of them are produced by the latter two methods, and the production of dialkylated products is controlled by increasing the amount of aniline, and the manufacturing cost is relatively high.

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