Process for the preparation of 5-chloro-2-hydroxy-4-alkyl-benzenesulfonic acids
AssigneeHoechst Aktiengesellschaft
InventorsWolfgang Tronich, Carl-Stephan Frohlich, Gunther Sell
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Abstract
Process for the preparation of compounds of the formula (1) ##STR1## in which R is an alkyl (C.sub.1 -C.sub.6) group and X is a hydrogen or alkali metal atom, in which compounds of the formula (2) ##STR2## in which R and X have the abovementioned meanings, are converted into the corresponding diazonium compound with a diazotizing agent in a mineral acid at temperatures of about -5.degree. C. to about +25.degree. C., this diazonium compound is then reacted, without or after intermediate isolation, with aqueous mineral acid at temperatures of about 70.degree. C. to about 120.degree. C. and the resulting compounds of the above formula (1) are isolated.
Claims20
A process for the preparation of a compound of the formula (1) ##STR6## in which R is an alkyl (C.sub.1 -C.sub.6) group and X is a hydrogen or alkali metal atom, which comprises converting a compound of the formula (2) ##STR7## in which R and X have the abovementioned meanings, into the corresponding diazonium compound with a diazotizing agent in a mineral acid at temperatures of about -5.degree. C. to about +25.degree. C., subsequently reacting this diazonium compound, without or after intermediate isolation, with aqueous mineral acid at temperatures of about 70.degree. C. to about 120.degree. C. to obtain the compound of the above formula (1).
Dependencies are inferred from the claim text.