Method for preparing 1,3-acetone dicarboxylic acid diester and intermediate thereof by oxidizing citric acid and hydrogen peroxide

The invention discloses a method for preparing 1,3-acetone dicarboxylic acid diester and an intermediate thereof by oxidizing citric acid and hydrogen peroxide. The method comprises the steps of: with hydrogen peroxide as an oxidizing agent, oxidizing citric acid in a water solution of citric acid at 0-100 DEG C to obtain 1,3-acetone dicarboxylic acid; and enabling the obtained 1,3-acetone dicarboxylic acid to be subjected to an esterification reaction with low-level fatty alcohol to obtain the 1,3-acetone dicarboxylic acid diester. The method disclosed by the invention is good in selectivity, high in transformation rate, free of environmental pollution and convenient for post treatment, thereby being an environment-friendly synthesis method; the method is a new synthesis method further satisfying atom economy rules; and moreover, the method is suitable for large-scale industrial production and the economic efficiency is greatly improved.