62855-71-4Relevant articles and documents
Preparation method of 2,4-dichlorophenoxyacetic ester
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, (2019/01/08)
The invention provides a preparation method of 2,4-dichlorophenoxyacetic ester, wherein the preparation method includes the following steps: S1) carrying out a reaction of phenol and methyl chloroacetate under alkaline conditions to obtain methyl phenoxyacetate; S2) carrying out selective chlorination reaction of methyl phenoxyacetate with a chlorinating agent under the action of a catalyst A anda catalyst B to obtain 2,4-methyl dichlorophenoxyacetate, wherein the catalyst A is Lewis acid, and the catalyst B is C5-22 thioethers, thiazoles, isothiazoles and thiophenes or halogenated derivatives thereof; and S3) carrying out transesterification reaction of 2,4-methyl dichlorophenoxyacetate and alcohol under the action of a catalyst, to obtain 2,4-dichlorophenoxyacetic ester, wherein the alcohol is C2-20 alcohol. The selective chlorination reaction is carried out with methyl phenoxyacetate as a raw material, the selectivity of the reaction is improved, the loss of effective components isavoided, the yield of the effective components is greatly improved, and the three-waste treatment capacity, the three-waste treatment difficulty and the treatment cost are reduced.
