Production of acetaminophen

摘要

N-acetyl-para-aminophenol is prepared by subjecting 4-hydroxyacetophenone oxime to a Beckmann rearrangement in the presence of a thionyl chloride catalyst and an alkyl alkanoate as the reaction solvent. An integrated process is disclosed wherein 4-hydroxyacetophenone is reacted with a hydroxyl amine salt and a base to obtain the ketoxime of the ketone, e.g., 4-hydroxyacetophenone oxime, extracting the ketoxime product from the reaction with alkanoate ester and subjecting the ketoxime dissolved in the ester to a Beckmann rearrangement in the presence of a thionyl chloride catalyst.