Process for the preparation of 6-chloro-2,4-dinitrophenol
AssigneeHoechst Aktiengesellschaft
InventorsOtto Arndt, Theodor Papenfuhs
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Abstract
A process for the preparation of 6-chloro-2,4-dinitrophenol in a high yield and in a high degree of purity by saponifying 2,4-dinitrochlorobenzene and/or 2,4-dinitrophenyl alkyl ethers of the formula ##STR1## in which m denotes the number 2, 3 or 4 and n denotes the number 1 or 2, by means of aqueous sodium hydroxide or potassium hydroxide solution and chlorinating the resulting 2,4-dinitrophenol with sodium hypochlorite, which comprises chlorinating the 2,4-dinitrophenol, without prior isolation as an intermediate, in aqueous suspension at a pH value of 3.5-7 by means of chlorine bleach liquor at temperatures of 5.degree. to 20.degree. C.
Claims8
A process for the preparation of 6-chloro-2,4-dinitrophenol in a high yield and in a high degree of purity by saponifying 2,4-dinitrochlorobenzene or 2,4-dinitrophenyl alkyl ethers of the formula ##STR4## in which m denotes the number 2, 3 or 4 and n denotes the number 1 or 2, by means of aqueous sodium hydroxide or potassium hydroxide solution and chlorinating the resulting 2,4-dinitrophenol with sodium hypochlorite, which comprises chlorinating the resulting 2,4-dinitrophenol, without prior isolation as an intermediate, in aqueous suspension at a pH value of 3.5-7 by means of chlorine bleach liquor at temperatures of 5.degree. to 20.degree. C.
A process for the preparation of 6-chloro-2,4-dinitrophenol in a high yield and in a high degree of purity by saponifying 2,4-dinitrochlorobenzene together with 2,4-dinitrophenyl alkyl ethers of the formula ##STR5## in which m denotes the number 2,3 or 4 and n denotes the number 1 or 2, by means of aqueous sodium hydroxide or potassium hydroxide solution and chlorinating the resulting 2,4-dinitrophenol with sodium hypochlorite, which comprises chlorinating the resulting 2,4-dinitrophenol, without prior isolation as an intermediate, in aqueous suspension at a pH value of 3.5-7 by means of chlorine bleach liquor at temperatures of 5.degree. to 20.degree. C.
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