PREPARATION OF TRIMETHYLHYDROQUINONE

PURPOSE:To prepare trimethylhydroquinone, economically, by thermally dealkylating a monoalkyl trimethylhydroquinone in the presence of a catalyst. CONSTITUTION:Trimethylhydroquinone is prepared by dealkylating the monoalkyl trimethylhydroquinone of formula (R is alkyl; R is H or CH3) in the presence of a catalyst such as inorganic acid (e.g. sulfuric acid, phosphoric acid, etc.), metallic oxide (e.g. alumina, silica, etc.) and/or a strongly acidic ion exchange resin having cation exchange group such as sulfonic acid group, etc. under heating preferably at about 120-300 deg.C, especially about 150-300 deg.C. The compound of formula used as the raw material can be prepared by various methods; however, the trimethylation of a monoalkylhydroquionone with methanol using a transition metal oxide such as iron oxide as a catalyst affords the objective raw material most easily an in high yield.