Some common heterocyclic compound, 660845-30-7, name is 5-Chloro-3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carbaldehyde, molecular formula is C6H5ClF2N2O, 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. Application In Synthesis of 5-Chloro-3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carbaldehyde
5-Chloro-3-(difluoromethyl)-l-methyl-lH-pyrazole-4-carboxylic acid (Example lib) (I la) (Mb)In a 500 mL round-bottom flask, 6.0 g (31 mmol) of 5-chloro-3-(difluoromethyl)-l-methyl-lH- pyrazole-4-carbaldehyde were taken up in 30 mL of toluene. A solution of 2.4 g (62 mmol) of sodium hydroxide in 6 mL of water was added to the reaction mixture, followed by 103 mL of a 30% strength solution of hydrogen peroxide in water. During the addition, the temperature was kept below 37 C. The reaction mixture was then stirred at 50 C for 7 h. After cooling, the organic phase was extracted with 100 mL of water. The aqueous phase was acidified to pH 2 using dilute hydrochloric acid. The white precipitate formed was filtered off, washed twice with 20 mL of water and dried. This gave 3.2 g of 5-chloro-3-(difluoromethyl)-l-methyl-lH-pyrazole-4-carboxylic acid as a white solid.’H NMR (400 MHz, DMSO- 6) delta ppm : 3.78 (s, 3H); 7.12 (t, 1H, JHF= 53.60 Hz); 13.19 (s, IR (KBr): 1688 cm_1 (C=0); 2200-3200 cm”1 broad;
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 660845-30-7, its application will become more common.
Reference:
Patent; BAYER CROPSCIENCE AG; BENTING, Juergen; COQUERON, Pierre-Yves; CRISTAU, Pierre; DAHMEN, Peter; DESBORDES, Philippe; DUBOST, Christophe; GARY, Stephanie; GREUL, Joerg; HADANO, Hiroyuki; VORS, Jean-Pierre; WACHENDORFF-NEUMANN, Ulrike; WO2012/65947; (2012); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics