| abstract |
Process for the preparation of enol ethers of the general formula I <IMAGE> by splitting off the radical R <4> OH from acetals or ketals of the formula II <IMAGE> in which the substituents R¹ and R² independently of one another are hydrogen, C1- to C12-alkyl, C3 - to C8-cycloalkyl, C3- to C8-cycloalkenyl, aryl optionally substituted by C1- to C4-alkyl or C7- to C16-aralkyl, R³ -CR <5> (OR <4>) 2, -COOR <4> or -COR <4>, R <4> C1- to C20-alkyl, C7- to C20-alkylaryl or C7- to C20-aralkyl, R <5> are hydrogen or C1- to C8-alkyl, characterized in that the reaction is carried out in the presence of phosphoric acid and / or hydrogen phosphates on a support material and / or phosphates and / or zeolites as catalysts. |