Electric Literature of 141573-95-7, A common heterocyclic compound, 141573-95-7, name is Ethyl 3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carboxylate, molecular formula is C8H10F2N2O2, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
Example 1Ethyl 5-chloro-1-methyl-3-difluoromethyl-1H-pyrazole-4-carboxylate (III-1) 20.25 g (100 mmol) of ethyl 1-methyl-3-difluoromethyl-1H-pyrazole-4-carboxylate and 40 ml of SO2Cl2 are placed under argon and the mixture is heated to 60 C. and stirred at this temperature for 8 hours. After diluting the mixture with ethyl acetate, washing with water and removing the solvent under vacuum, 21 g of the product are obtained with an HPLC purity of 94%. M.p. 37-39 C.1H NMR (CDCl3): delta=7.1 (1H, t), 4.3 (q, 2H), 3.9 (s, 3H), 1.4 (t, 3H) ppm.19F NMR (CD3CN): delta=-114.9 (2F, t) ppm.
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.
Reference:
Patent; Bayer CropScience AG; US2011/288305; (2011); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics