| 摘要 |
An improved process for preparing lower unsaturated ketones by reacting the corresponding alpha,beta-unsaturated alcohols with alkyl acetoacetates in a Carroll reaction in the presence of from 0.1 to 5 mol %, based on the alkyl acetoacetate to be reacted, of an organic aluminum compound as catalyst with elimination and continuous removal by distillation of the alkanol eliminated during the reaction from the alkyl acetoacetate in a reactor system with a fitted fractionation column, whereinA an alpha,beta-unsaturated alcohol which boils below 140° C. is introduced, in the absence of effective amounts of a solvent, together with the organic aluminum compound into the reaction vessel,B a reaction temperature which is as constant as possible between 170° C. and 250° C. is set under elevated pressure,C at this temperature, the alkyl acetoacetate is metered into the mixture, obtained in A, of the alpha,beta-unsaturated alcohol and the organic aluminum compound, andD during the reaction the content of alkyl acetoacetate in the reaction mixture is set at a value which is as constant as possible between 0.1 and 10% by weight.
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