GB616330A - Improvements in the manufacture of aryl alkyl ketones and carbinols - Google Patents

Abstract

Aryl-alkyl ketones with or without the corresponding carbinols or of nuclear halogen substitution derivatives thereof are prepared by the partial oxidation of normal or secondary alkyl aromatic hydrocarbons containing at least one ethyl or higher alkyl group or of nuclear halogen substitution derivatives thereof, wherein the hydrocarbon or halogenated hydrocarbon is heated in the liquid phase, e.g. at a temperature above 100 DEG C. and in the presence of an oxidation catalyst comprising a metal salt with oxygen which is under a partial pressure above 25 lbs. per sq. in., e.g. at least 50 lbs. per sq. in. The oxidation catalyst may be soluble in the hydrocarbon or halogenated hydrocarbon. Suitable catalysts are manganese and cobalt salts of organic acids, e.g. salts of lower fatty acids such as acetates, salts of higher fatty acids such as palmitates or stearates or of cyclic aliphatic acids such as naphthenates or of aromatic acids especially monocarboxylic aromatic acids such as benzoates, and salts of iron, copper or lead. Alkaline earth metal salt especially barium acetate may also be present. A water binding agent may present, e.g. on organic acid anhydride such as acetic anhydride capable under the conditions prevailing of esterifying the carbinol formed and the carbinol is obtained at least partly in the form of the corresponding ester. The organic acid anhydride may be present in a quantity equal to at least one molecular proportion of the anhydride. In examples: (1) oxygen under 100 lbs. pressure is passed into an autoclave containing ethyl benzene with anhydrous manganese acetate in suspension and maintained at 150 DEG C. to give a mixture of acetophenone, phenyl methyl carbinol and benzoic acid; (2) as in example (1) using as catalyst a mixture of manganese and barium acetates; (3) oxygen is passed into an autoclave at 50 lbs. pressure and 130 DEG C. containing equimolecular amounts of ethyl benzene and acetic anhydride with anhydrous manganese acetate as catalyst to give the same products as in example (1).