Sodium Phosphate, Dibasic → HCID 22120898, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-(furan-2-yl)pyrazole (0.46 g) in dimethylformamide (15 ml) and water (5 ml) was added sodium dithionite (0.286 g) and disodium hydrogen phosphate (0.17 g). The mixture placed in a 400 ml Parr vessel, which was evacuated, then charged with trifluoromethylbromide gas to 40 psi. The mixture was shaken and heated at 45° C., for 3 hours, then left at room temperature for 16 hours. The vessel was then evacuated, then recharged with trifluoromethylbromide to 40 psi, then shaken and heated to 45° C. for a further 9 hours, then left at room temperature for 48 hours. The vessel was then evacuated, then recharged with trifluoromethylbromide to 40 psi, then shaken and heated to 45° C. for a further 7 hours, then left at room temperature for 16 hours. The mixture was filtered and then poured into brine (25 ml) and extracted with ether (25 ml, ×3). The combined organic layers were washed with water (20 ml), dried (Na2SO4), and evaporated. The residue was purified by column chromatography on silica gel (25 g) eluted with hexane:ether (50:50 changing gradually to 20:80). Combination and evaporation of suitable fractions gave the title compound as a pale yellow solid, m.p. 148-151° C.

Provenance & Evidence