Pigment violet 23 explained

Pigment violet 23 is an organic compound that is a commercial pigment. It is member of the dioxazine family of heterocyclic compounds, but derived from carbazoles.^[1] It is prepared by condensation of chloranil and 3-amino-N-ethylcarbazole. It has a centrosymmetric angular structure.^[2] For many years, the structure was assigned, incorrectly, as having a "linear structure" (EC no. 228-767-9, CAS RN 6358-30-1) which differ in terms of the carbazole ring fusion.^[3]

Pigment violet 23 is prepared by condensation of an aniline with chloranil.^[4]

References

1. Chamberlain, Terence "Dioxazine violet pigments" from High Performance Pigments Edited by Smith, Hugh M. 2002, 185–194.
2. Panina, N.; van de Ven, R.; Verwer, P.; Meekes, H.; Vlieg, E.; Deroover, G. "Polymorph prediction of organic pigments" Dyes and Pigments 2008, volume 79, 183–192.
3. Book: Heinrich Zollinger. Color Chemistry Syntheses, Properties, and Applications of Organic Dyes and Pigments. 2003. John Wiley & Sons . 3-906390-23-3. 118.
4. Horst Tappe, Walter Helmling, Peter Mischke, Karl Rebsamen, Uwe Reiher, Werner Russ, Ludwig Schläfer and Petra Vermehren "Reactive Dyes"in Ullmann's Encyclopedia of Industrial Chemistry 2000, Wiley-VCH, Weinheim.