PRODUCTION OF P-PHYDROXYBENZALDEHYDE

PURPOSE:To obtain the titled compound at a low cost on an industrial scale, facilitating the recovery and reuse of methanol solvent, by using a solvent composed of methanol containing a specific amount of water and oxidizing p-cresol, etc., with O2, etc., in the presence of a cobalt compound and a base. CONSTITUTION:p-Cresol or a cresol mixture containing the same is oxidized with O2 or an O2-containing gas of 1-100 atm pressure in a methanol solvent containing 0.5-10wt% water in the presence of a cobalt catalyst such as bivalent cobalt acetate tetrahydrate, etc., and a base such a NaOH at 0-300 deg.C under atmospheric or positive pressure to obtain the objective compound. The amount of the hydrated methanol in the oxidation reaction is usually 1-20pts. wt. per 1pt.wt. of p-cresol. EFFECT:Water can be easily removed from recovered methanol. The rate of oxidation reaction can be maintained at a level comparable to the level attained by the use of almost anhydrous methanol. USE:Raw material in the field of organic chemical industry.