Hydrochloric Acid → (E)-2-(fluoromethylene)-4-(p-fluorophenyl)butan-1-ol

Participants

Reaction Steps

Cool to 0° C. a solution of diisobutylaluminum hydride (7.64 kg, 25% by weight in toluene, 13.42 mol). Add a solution of ethyl (E)-2-(fluoromethylene)-4-(p-fluorophenyl)butyrate (1.74 kg, 74.1% by weight in toluene, 5.37 mol) at such a rate that the temperature of the reaction mixture does not rise above 20° C. After the addition is complete, warm to ambient temperature. After 2 hours, cool to 0° C. Slowly, add methanol (7.73 kg) at such a rate that the temperature of the reaction mixture does not rise above 15° C. Cool to 0° C. Slowly, add water (7.96 kg) at such a rate that the temperature of the reaction mixture does not rise above 20° C. Add a concentrated aqueous solution of hydrochloric acid (7.59 kg). Warm to ambient temperature. Separate the organic layer and dry azeotropically by distillation in vacuo until the volume of the organic layer is about one half of its original volume to give the title compound as a solution in toluene.

Provenance & Evidence