Basf Aktiengesellschaft

Barbara Jessel

Ulrich Hoercher

Peter Lechtken

Harald Laas

Bernhard Bockstiegel

Paul Grafen

2,3,5-Trimethyl-p-benzoquinone is prepared by oxidation of trimethylphenol with oxygen or an oxygen-containing gas in the presence of a catalyst containing a copper(II) halide in a two-phase reaction medium consisting of water and an aliphatic alcohol at elevated temperatures by a process in which the reaction is carried out in a mixture of water and a saturated aliphatic alcohol of 12 to 18 carbon atoms, having a flashpoint greater than 120.degree. C., such as 1-dodecanol, 1-tetradecanol, 1-hexadecanol or 1-octadecanol, in particular 1-dodecanol, and at from 60.degree. to 100.degree. C. Particularly good yields of TMQ are obtained if the reaction is carried out in the presence of a copper(II) halide, such as CuCl.sub.2 or CuBr.sub.2, and of an alkaline earth metal halide, in particular CaCl.sub.2 or MgCl.sub.2, or of an alkali metal halide, in particular LiCl or NaCl, as the catalyst system.

Preparation of 2,3,5-trimethyl-p-benzoquinone

d-.alpha.-Tocopherol is prepared from a mixture obtained from natural intermediates and containing .alpha.-, .beta.-, .gamma.- and .delta.-tocopherols, by methylation at the aromatic ring of the tocopherols by reaction with formaldehyde or with a compound which donates formaldehyde under the reaction conditions, and subsequent catalytic hydrogenation, by a process in which the reaction with formaldehyde or with the formaldehyde donor is carried out at from 150.degree. to 200.degree. C. in the presence of an alkyl ester of phosphoric or phosphorous acid.

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Ludwigshafen, Germany

Barbara Jessel