| 摘要 |
PROBLEM TO BE SOLVED: To simply obtain the subject compound useful as the intermediate of a cyanide coupler for color photography in high purity. SOLUTION: This method for producing the 2,4-dichloro-3-ethyl-6-nitrophenol of formula I comprises sulfonating 4-chloro-3-ethylphenol of formula II with fuming sulfate (28-65% concentration) in an organic solvent (e.g. methylene chloride) preferably at 10-50 deg.C chlorinating the produced 5-chloro-4-ethyl-2- hydroxybenzene-sulfonic acid with chlorine gas in an aqueous solvent, converting the produced 3,5-dichloro-4-ethyl-2-hydroxybenzenesulfonic acid into a sulfonic acid, depositing the sulfonic acid, and further nitrating the sulfonic acid with nitric acid or a nitrate.
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