摘要 |
A process for the preparation of the unsaturated dinitroaniline, ethalfluralin, having a level of nitrosamines lower than 0.5 ppm and essentially free from the compound of addition of halogenhydric acid on the methallyl double-bond, by treatment wlth aqueous halogenhydric acid, wherein crude ethalfluralin is treated under agitation with an aqueous solution of hydrobromic acid in the presence of sulfamic acid and of a sulfur compound selected from the groups consisting of bisulfites, metabisulfites, hydrosulfites, sulfurous acid and gaseous sulfur dioxide.
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