Acetic Anhydride → HCID 136477422, compound

Participants

Reaction Steps

A mixture of 40 g of 2',5'-difluoro-2-hydroxy-4-methoxybenzophenone hydrochloride and 230 ml of pyridine is refluxed overnight. The pyridine is evaporated in vacuo. The residue is partitioned between 5% hydrochloric acid and ethyl acetate. The ethyl acetate solution is dried over anhydrous sodium sulfate and evaporated. The residue was triturated with hexane to give E-2',5'-difluoro-2-hydroxy-4-methoxybenzophenone oxime. A mixture of 35 g of the oxime and 25.6 g of acetic anhydride is placed in an oil bath at 60° C. for 45 min. The reaction mixture is partitioned between ether and sodium bicarbonate solution. The ether extract is dried over anhydrous sodium sulfate and evaporated. Recrystallization of the residue from 95% ethanol gives 30 g of E-2',5'-difluoro-2-hydroxy-4-methoxybenzophenone O-acetyl oxime, mp 110°-111° C.

Provenance & Evidence