| 摘要 |
A process for the preparation of alkylphenols of the formula I <IMAGE> (I) in which R1, R2, R3, R4, and R5 stand for hydrogen or C1-C8 alkyl, by reaction of an alkylcyclohex-2-en-1-one of the formula II <IMAGE> (II) in which R1, R2, R3, R4, and R5 have the aforementioned meanings, at temperatures of from 200 DEG to 400 DEG C. and pressures ranging from 0.01 to 50 bar in the presence of palladium-on- alpha -Al2O3 catalysts, wherein the catalyst used has a specific surface area (BET) of from 1 to 10 m2/g, a pore diameter of from 5 nm to 300 mu m and a pore volume of from 0.1 to 0.5 cm3/g, from 80 to 100% of the pores having a diameter of from 40 to 400 nm, and also novel palladium-on- alpha -Al2O3 catalysts as obtained from a fine-grained alumina powder by steps of molding, pyrolysis and calcination.
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