Sodium Thiosulfate → methyl 4-(5-bromo-4-(difluoromethyl)thiazol-2-yl)-1-methyl-1H-pyrazole-5-carboxylate

Participants

Reaction Conditions

Reaction Steps

N-bromosuccinimide (391 mg) was added to an N,N-dimethylformamide (3.6 ml) solution of the methyl 4-(4-(difluoromethyl)thiazol-2-yl)-1-methyl-1H-pyrazole-5-carboxylate (200 mg) obtained in (Example 1.3) <Step 1>, and the obtained mixture was then stirred in a nitrogen atmosphere at 80° C. for 40 minutes. Thereafter, N-bromosuccinimide (391 mg) was further added to the reaction solution, and the obtained mixture was then stirred in a nitrogen atmosphere at 80° C. for 15 hours. Thereafter, a sodium thiosulfate aqueous solution (40 ml) and a saturated sodium hydrogen carbonate aqueous solution (60 ml) were successively added to the reaction solution, and the reaction mixture was then extracted with ethyl acetate (60 ml) twice. Organic layers were gathered. The gathered organic layer was washed with a saturated saline (100 ml) three times, and was then dried over anhydrous sodium sulfate. The solvent was distilled away under reduced pressure, and the obtained residue was then dried under reduced pressure, so as to obtain the title compound (274 mg) in the form of a brown solid.

Provenance & Evidence