| 摘要 |
FIELD: organic synthesis. ^ SUBSTANCE: invention relates to methods for preparing alkylenaminopolycarboxylic acids and, in particular, ethylenediamine-N,N,N',N'-tetrapropionic acid used as complexion agent in chemical industry, agriculture, and medicine. A novel method resides in reaction of ethylenediamine with beta-chloropropionic acid sodium salt as prepared by neutralization of beta-chloropropionic acid with sodium hydroxide aqueous solution at elevated temperature not exceeding 85°C and pH 9.0-11.0. Reaction mixture is then desalted, acidified to pH 1.5-2.0 at 10-15°C, neutralized with triethylamine to pH 4.0-4.5 at 5-10°C, and thus isolated desired product is with distilled water. ^ EFFECT: simplified synthetic scheme, reduced expenses and power consumption. ^ 4 cl |
