申请人:Hoechst Aktiengesellschaft
公开号:US04710322A1
公开(公告)日:1987-12-01
The invention consists in an improved process for the preparation of salts of benzaldehyde-2,4-disulfonic acid from 2,4-dichlorobenzaldehyde. In the process 2,4-di-chlorobenzaldehyde is reacted with an aqueous solution of an alkali metal or alkaline earth sulfite and/or hydrogensulfite for a reaction time of less than 7 hours at 140.degree.-180.degree. C. to form the corresponding salt of benzaldehyde-2,4-disulfonic acid with high yield. The product has application in the electroplating industry and in the preparation triphenylmethane dyestuffs.
本发明涉及从2,4-二氯苯甲醛制备苯甲醛-2,4-二磺酸盐的改进工艺。在该工艺中,将2,4-二氯苯甲醛与碱金属或碱土金属亚硫酸盐和/或氢亚硫酸盐的水溶液反应,反应时间小于7小时,反应温度为140-180°C,高产率地形成相应的苯甲醛-2,4-二磺酸盐。该产品在电镀工业和三苯甲烷染料的制备中具有应用。