(Diethylamino)sulfur trifluoride → HCID 9924669, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 5-amino-4-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-hydroxymethylpyrazole (1.25 g) in dichloromethane (10 ml) was added slowly to a stirred solution of diethylaminosulphur trifluoride (0.66 g) in dichloromethane (6 ml) cooled to −78° C. After 30 minutes at this temperature the solution was warmed to room temperature and stirred for 2 hours. The mixture was then poured onto water (20 ml) and the dichloromethane layer was separated, dried over anhydrous magnesium sulphate, filtered and evaporated in vacuo. The product was purified by chromatography on silica (Merck, 40-230 mesh, 0.7 kg cm−2) eluting with a mixture of dichloromethane and ethyl acetate (98:2), and subsequent recrystallization from dichloromethane-petroleum ether to give 5-amino-4-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-fluoromethylpyrazole as a white solid m.p. 139-141° C.

Provenance & Evidence