Preparation of gamma , delta -unsaturated ketones by the Carroll reaction, novel catalysts therefor and the preparation thereof

摘要

A process for preparing gamma , delta -unsaturated ketones of the general formula I by reacting an allyl alcohol of the general formula II in which R1 is H or a hydrocarbon radical having 1 to 20 carbon atoms, with diketene or an alkyl acetoacetate of the general formula III in which R2 is alkyl having 1 to 4 carbon atoms in an unmodified or modified Carroll reaction in the presence of an aluminum catalyst, wherein aluminum compounds which are stable liquids at room temperature, or a mixture of such aluminum compounds, which comprise at least one radical formed from an alkyl acetoacetate and 1 or 2 alkoxy radicals, or else comprise exclusively radicals formed from alkyl acetoacetates, which are esterified with sec-butanol or isobutanol, or else are esterified with at least two different alcohols, are used as aluminum catalyst. Also claimed are the novel mixtures of aluminum compounds which comprise radicals which are formed exclusively from alkyl acetoacetates and are esterified with at least two different alkanols, and the batchwise and continuous preparation of the liquid aluminum catalysts.