Method for producing anthraquinone compounds
AssigneeSumitomo Chemical Company, Limited
InventorsMakoto Hattori, Satoshi Kajitani
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Abstract
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.
Claims9
A method for producing an anthraquinone compound having the formula (III) ##STR8## where R is a hydrogen atom, or an unsubstituted or substituted alkyl or cycloalkyl group, which comprises reacting a compound having the formula (I), or a salt thereof ##STR9## wherein R is defined as above and X is an hydrogen atom or a sulfonic acid group, in an aqueous medium with a cyanogenating agent in the presence of a compound of the formula (II),
- HO--A-O).sub.n R' (II)
- wherein A is a bivalent aliphatic saturated hydrocarrbon residual group having 2 to 4 carbon atoms, R' is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and n is a number of from 1 to 100, the compound of formula (II) being present in an amount of from 2 to 90% by weight based on the total weight of the compound of the formula (II) and the aqueous medium, containing no quaternary ammonium or quaternary phosphonium compound.
A method according to claim 5, wherein the total weight of the compound of the formula (II) and the aqueous medium ranges from 2 to 30 times by weight the weight of the compound of the formula (I).
Dependencies are inferred from the claim text.