PURPOSE: To obtain the titled compound useful as an intermediate for various chemicals such as drug modulator, cosmetic, etc., from glyoxal as a raw material, to improve selectivity, by separately adding an aqueous solution of hydrogen peroxide and ferrous ion to a reaction mixture.
CONSTITUTION: An aqueous solution of hydrogen peroxide and ferrous ion are separately added to glyoxal of raw material, which is oxidized to give the aimed compound. 5W60wt% aqueous solution of hydrogen peroxide is preferably used and preferably the aqueous solution of hydrogen peroxide as an oxidizing agent is added to glyoxal. Ferrous sulfate, etc., are used as the ferrous ion and preferably added continuously or intermittently during the reaction process. The amount of the ferrous ion used is ≥about 0.01mol, preferably about 0.5mol based on 1mol glyoxal. The reaction is preferably carried out at 0W30°C while preventing the reaction system from coming into contact with a gas phase containing molecular oxygen such as air, etc.
ASANO SHIRO
SAKAMOTO TOSHIHIKO
