Process for the preparation of 4-(2-aminophenylthio)naphthalic anhydride derivatives
AssigneeCassella Aktiengesellschaft
InventorsWolfgang Bauer, Wassilis Koumbouris
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Abstract
4-(2-Aminophenylthio)naphthalic anhydride derivatives are obtained in good yields and purities by reaction of 2-aminothiophenolates with 4-chloro- or 4-bromonaphthalic anhydrides having a particle size of at most 50 .mu.m.
Claims23
Process for the preparation of 4-(2-aminophenylthio)naphthalic anhydride derivatives of the formula I ##STR4## in which R denotes H, methyl, ethyl, methoxy, ethoxy or chlorine, comprising reacting 4-halonaphthalic anhydrides of the formula II ##STR5## in which X denotes chlorine or bromine, with 2-aminothiophenolates of the formula III ##STR6## in which R has the meaning mentioned above and M.sup..sym. is selected from the group consisting of an alkali metal cation, ammonium ion and a substituted ammonium ion;
- wherein said 4-halonaphthalic anhydride of the formula II employed has a maximum particle size of about 50 .mu.m.
Dependencies are inferred from the claim text.