Tert-Butyl nitrite → HCID 86644440, compound

Participants

Reaction Steps

0.9 g of 5-amino-1-{2-fluoro-4-methyl-5-(2,2,2-trifluoroethylthio)phenyl}-3-{1,1,2-trifluoro-2-(trifluoromethoxy)ethoxy}pyrazole was dissolved in 30 mL of acetonitrile, and 0.27 g of N-chlorosuccinimide was added under cooling with ice. After stirring for 10 minutes under cooling with ice, the solvent was distilled off under reduced pressure, extraction with ethyl acetate was carried out, and the organic layer was dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure, and the obtained residue was purified by column chromatography (developing solvent ethyl acetate:hexane=1:4) to obtain 5-amino-4-chloro-1-{2-fluoro-4-methyl-5-(2,2,2-trifluoroethylthio)phenyl}-3-{1,1,2-trifluoro-2-(trifluoromethoxy)ethoxy}pyrazole. Then, the obtained pyrazole derivative was dissolved in 30 mL of tetrahydrofuran, and 0.3 mL of t-butyl nitrite was added under cooling with ice. After stirring at room temperature for 12 hours, the solvent was distilled off under reduced pressure, and the obtained residue was purified by column chromatography (ethyl acetate:hexane=1:10) to obtain 0.75 of 4-chloro-1-{2-fluoro-4-methyl-5-(2,2,2-trifluoroethylthio)phenyl}-3-{1,1,2-trifluoro-2-(trifluoromethoxy)ethoxy}pyrazole.

Provenance & Evidence