Process for the preparation of 2,3,5-trimethylbenzoquinone.

摘要

A process for preparing 2,3,5-trimethylbenzoquinone (TMBQ) from 2,3,6-trimethylphenol (TMP), which comprises contacting TMP with oxygen or oxygen-containing gas in an aqueous solution of a catalyst comprising a copper halogeno complex represented by the general formula (I) and an alkali metal halide; M l [Cu(II)mXn]p (I) said contact reaction of TMP with the oxygen or the oxygen-containing gas being carried out semi-batchwise while continuously adding a solution of TMP in a specified alcohol to the aqueous solution of the catalyst to which a specified alcohol, cupric hydroxide, cuprous chloride or a mixture thereof is previously added. The present process yields various advantages as follows: (1) TMBQ can be produced with high selectivity, (2) TMBQ can be easily separated from the reaction mixture, (3) The amount of the catalyst consumed can be greatly reduced, and (4) Reuse of the catalyst can be easily accomplished.