Title:
METHOD FOR PREPARING BIFENAZATE
Document Type and Number:
WIPO Patent Application WO/2023/000616
Kind Code:
A1
Abstract:
The present invention relates to the technical field of synthesis of pesticides and intermediates, and in particular to a method for preparing bifenazate. The preparation method comprises taking a compound as represented by formula (I) and isopropanol as raw materials, and performing a transesterification reaction on same. Provided in the present invention is a method for obtaining bifenazate as represented by formula (II) by means of taking a compound as represented by formula (I) and isopropanol as raw materials, and performing a transesterification reaction on same. The method avoids the use of high-price isopropyl chloroformate as a reaction raw material, and overcomes the defect of a reaction between isopropyl chloroformate and hydrazine hydrochloride tending to generate more double-linked impurities, resulting in a low yield of bifenazate products. In addition, few impurities are generated by means of the preparation method of the present invention, the obtained product is easy to purify, the yield of the product is high, and the production cost is low.
Inventors:
XING WENLONG (CN)
SUN FEI (CN)
SUN FEI (CN)
Application Number:
PCT/CN2021/142818
Publication Date:
January 26, 2023
Filing Date:
December 30, 2021
Export Citation:
Assignee:
PURPANA BEIJING TECH CO LTD (CN)
International Classes:
C07C281/02
Foreign References:
| CN102344395A | 2012-02-08 | |||
| CN109988084A | 2019-07-09 | |||
| CN103193683A | 2013-07-10 | |||
| CN1075952A | 1993-09-08 | |||
| US6706895B1 | 2004-03-16 |
Attorney, Agent or Firm:
CN-KNOWHOW INTELLECTUAL PROPERTY AGENT LIMITED (CN)
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