Process for preparing glyoxylic esters or their hydrates in which a water-soluble salt of a maleic or fumaric monoester or a mixture thereof is reacted with ozone in aqueous solution at temperatures of from 0 to 50.degree. C., and the corresponding glyoxylic ester or its hydrate is isolated from the resulting reaction mixture.
在制备甘醛酸酯或其
水合物的过程中,通过在0至50摄氏度的
水溶液中,将
顺丁烯二酸或
呋喃二酸单酯的
水溶性盐或二者的混合物与
臭氧反应,然后从产生的反应混合物中分离出相应的甘醛酸酯或其
水合物。