660845-30-7, name is 5-Chloro-3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carbaldehyde, belongs to pyrazoles-derivatives compound, is considered to be a conventional heterocyclic compound, which is widely used in drug synthesis. The chemical synthesis route is as follows. Recommanded Product: 660845-30-7
Step 1 : preparation of of 5-chloro-3-(difluoromethyl)-1-methyl-1 H-pyrazole-4-carboxylic acid (Ilia)In a 500 ml flask, 6.0 g (31 mmol) of 5-chloro-3-(difluoromethyl)-1-methyl-1 H-pyrazole-4-carbaldehyde are added to 30 ml of toluene. A solution of 2.4 g (62 mmol) of sodium hydroxide in 6ml of water is added to the reaction mixture, followed by 103 ml of a 30% solution of hydrogen peroxide in water, whilst keeping the temperature below 37C. After the end of the addition, the reaction mixture is stirred at 50C for 7 hours. Once the reaction mixture is back to room temperature, the two phases are separated and the organic phase is extracted with 100 ml of water. The combined aqueous phases are acidified to pH 2 with aqueous hydrochloric acid. The resulting white precipitate is filtered, washed twice with 20 ml of water, and dried to yield 3.2 g of 5-chloro-3-(difluoromethyl)-1-methyl-1 H-pyrazole-4-carboxylic acid as a white solid. H NMR (400 MHz, DMSO-c/6) delta ppm : 3.78 (s, 3H); 7.12 (t, 1 H, JHF = 53.60 Hz)13.19 (s, 1 H); IR (KBr) : 1688 cm”1 (C=0); 2200-3200 cm”1 broad (hydrogen bond).
The synthetic route of 660845-30-7 has been constantly updated, and we look forward to future research findings.