Anthraquinone dye used for a color filter of a lcd

A method for synthesis of an asymmetric 1,4-diaminoanthraquinone compound wherein the amino groups are substituted with different groups selected from alkyl, aryl and alkylaryl groups, comprising the steps of:

• (A) reacting in the presence of at least one catalyst a mixture of 2,3-dihydro-9,10-dihydroxy-1,4-anthraquinone and 1,4-dihydroxyanthraquinone with a compound represented by the formula (3),
• R1—NH2 (3)
• wherein R1 is an aryl group, alkyl group or an arylalkyl group, R1 can be substituted by the group selected from the group consisting of hydroxyl group, amino group, thiol group, alkyl group having 1 to 20 carbon atoms, aryl group or combination thereof to form a first intermediate, and
• (B) reacting in the presence of at least one catalyst the first intermediate with a compound represented by the formula (4)
• R2—NH2 (4)
• wherein R2 is an aryl group, alkyl group or an arylalkyl group, R2 can be substituted by the group selected from the group consisting of hydroxyl group, amino group, thiol group, alkyl group having 1 to 20 carbon atoms, aryl group or combination thereof, and R1 and R2 are different.

A method for synthesis of an asymmetric 1,4 bis(arylamine)anthraquinone compound, comprising the steps of:

• (A) reacting in the presence of boric acid a mixture of 2,3-dihydro-9,10-dihydroxy-1,4-anthraquinone and 1,4-dihydroxyanthraquinone with a compound represented by the formula (5)
• Ar1—NH2 (5)
• wherein Ar1 is aryl group substituted by at least one group selected from the group consisting of hydroxyl group, amino group, thiol group, alkyl group having 1 to 20 carbon atoms, aryl group or combination thereof to form a first intermediate, and
• (B) reacting in the presence of boric acid, metal zinc and an acid the first intermediate with a compound represented by the formula (6)
• Ar2—NH2 (6)
• wherein Ar2 is aryl group substituted by at least one group selected from the group consisting of hydroxyl group, amino group, thiol group, alkyl group having 1 to 20 carbon atoms, aryl group or combination thereof, and the substituent of Ar1 and the substituent of Are are different.