Synthesis of aminocarbazole–anthraquinone fused dyes and polymers

A new series of dyes have been synthesized by Buchwald-type coupling of 3-aminocarbazole with various isomers of chloroanthraquinone. The absorption maxima of the resulting dyes were found to vary from 542 nm (violet) to 777 nm (green) depending on the extent of conjugation. Also, three different polymers have been synthesized by coupling of 3,6-diaminocarbazole with isomers of dichloroanthraquinone under palladium-catalyzed conditions. We demonstrated that the conjugation length in these polymers was largely confined to their monomer repeat units.