Ethyl Bromide → HCID 22618612, compound

Participants

Reaction Steps

A solution of ethyl magnesium bromide, prepared from magnesium (0.57 g) and ethyl bromide (2.6 g) in dry diethyl ether (25 ml), was added dropwise to a stirred solution of 5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-thiocyanato-3-trifluoromethylpyrazole (5.0 g) in dry ether (50 ml) at -20° C. After stirring for a further 2 hours at room temperature, water (130 ml) was carefully added, and stirring maintained for 0.25 hour. The ether layer was separated, dried over anhydrous magnesium sulphate, and evaporated in vacuo to give a yellow gum. Purification by chromatography on silica (Merck, 230-400 mesh, 0.7 kg cm-2) eluting with dichloromethane-petroleum ether (1:1) gave a product, which recrystallized from hexane to furnish 5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-ethylthio-3-trifluoromethylpyrazole, in the form of white needles, m.p. 116°-116.5° C.

Provenance & Evidence