摘要:
Anthraquinone compounds of the formula, ##STR1## wherein R is hydrogen, alkyl or cycloalkyl, which are useful as intermediates for disperse dyes and as sublimable dyes for thermal transfer recording, are prepared by allowing the compound of the formula, ##STR2## wherein X is hydrogen or sulfonic acid group, to react with a cyanogenating agent in an aqueous medium in the presence of a compound, such as polyalkylene glycols.
摘要:
1,4-Diaminoanthraquinone-2,3-disulfonic acid or salt thereof and 1,4-diaminoanthraquinone-2,3-dinitrile which are intermediate of anthraquinone dyes are economically prepared by allowing 1,4-diamino-2,3-dihalogenoanthraquinone to react with alkalimetal sulfite in aqueous solution in the presence of quaternary ammonium or phosphonium compound, while water is being removed, to obtain 1,4-diaminoanthraquinone-2,3-disulfonic acid or salt thereof and, if necessary, cyanogenating the reaction mixture above without removing the disulfonic acid or salt thereof produced above to obtain 1,4-diaminoanthraquinone-2,3-dinitrile. The quaternary ammonium or phosphonium compound is recovered from and re-used for the reactions above.