Improvements in or relating to processes for preparing alkyl aryl ketones and the improved alkyl aryl ketones resulting therefrom

摘要

Alkyl aryl ketones are prepared by reacting an aliphatic acid and an aromatic compound, having as a substituent an alkyl, cycloalkyl or alkoxy radical, in the presence of phosphorus pentoxide in the disperse phase. The reaction may be carried out with or without heating in the presence or absence of solvents and under pressure or vacuum. The invention is illustrated by 12 examples of which the first is typical, as follows: m-xylene and acetic acid are refluxed with phosphorus pentoxide for two hours. The organic layer is separated and distilled under reduced pressure to give 2 : 4-dimethyl acetophenone and dimethyl diacetyl benzene. Other examples use toluene, cyclohexyl benzene, tert-butyl benzene, anisole, phenetole, and mesitylene as the aromatic components and acetic, propionic, and stearic acids as the acid components.