Bayer Aktiengesellschaft

Peter Wimmer

Hans-Josef Buysch

Lothar Puppe

Heinrich Pelster

Christian Froehlich

N,N-dialkylanilines can be prepared by reacting the anilines on which they are based with lower alcohols or with the corresponding ethers, at an increased temperature in the gas phase in the presence of a proton-containing zeolite catalyst of the pentasil type having an SiO.sub.2 /Al.sub.2 O.sub.3 ratio of &gt;60, it being advantageous to carry out the alkylation process under a pressure of 2-30 bar.

Process for the preparation of N,N-dialkylaniline

Anilines or N-alkyl-anilines are advantageously reacted with alkyl alcohols or the associated dialkyl ethers at elevated temperature in the gas phase, if a .gamma.-Al.sub.2 O.sub.3 is used that is prepared by dehydration of an aluminum oxide/hydroxide hydrate and has a BET surface area from 50 to 400 m.sup.2 /g and a surface acidity of 5 to 600 mmol H.sup.+ /kg.

Process for the preparation of N-alkylated anilines

Thymol can be prepared by reaction of m-cresol with propene at elevated temperature and at atmospheric to superatmospheric pressure by using wide- and medium-pored zeolites which have a pore diameter of at least 5 .ANG. as heterogeneous catalysts.

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Krefeld, Germany

Peter Wimmer