Method for synthesizing fluopyram

Abstract

The invention provides a method for synthesizing fluopyram. The method comprises the following steps: taking commercially available 2-bromoethylamine hydrobromide as an initial raw material, carrying out self nucleophilic substitution reaction under an alkaline condition to prepare cyclopropylamine, and reacting the cyclopropylamine with o-trifluorobenzoyl chloride to obtain a key intermediate cyclopropylamine-1-yl (2-(trifluoromethyl) phenyl) ketone; and reacting 2,3-dichloro-5-trifluoromethylpyridine with the cyclopropylamine-1-yl (2-(trifluoromethyl) phenyl) ketone under the action of lithium alkylide to prepare the fluopyram. According to the method for synthesizing the fluopyram through the three-step reaction, the first-step reaction and the second-step reaction are one-pot reactions, the reaction yield is high, the synthesis process is simple, the product purity is high, and the method has huge application value.

Description

technical field

[0001] The invention relates to the fields of organic synthesis and fine chemicals, in particular to a method for synthesizing fluopyram. Background technique

[0002] Fluopyram (trade name: Lufida), its chemical name is N-[2-[3-chloro-5-(trifluoromethyl)-2-pyridyl]ethyl]-2-trifluoromethyl Benzyl benzamide, cas: 658066-35-4, is a succinate dehydrogenase inhibitor fungicide developed by Bayer Crop Science, except for grapes, pears, bananas, apples, cucumbers, tomatoes and other vegetables and fields In addition to the prevention and control of spotted leaf spot, leaf spot, gray mold, powdery mildew, sclerotinia, early blight, etc. on crops, it is also a high-efficiency, green, and low-toxic nematicide for plant protection (WO2020020897 ).

[0003] The synthetic method about fluopyridinamide in current literature mainly contains:

[0004] Route 1:

[0005]

[0006] Patent documents WO2004016088 and WO2018114484 disclose that 2,3-dichloro-5-trifluoromethy...

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