Pigment Yellow 13

Pigment Yellow 13 is an organic compound and an azo compound. It is a widely used yellow pigment. It is also classified as a diarylide pigment, being derived from 3,3'-dichlorobenzidine. It is closely related to Pigment Yellow 12, wherein the two xylyl groups are replaced by phenyl and to Pigment Yellow 14 where the xylyl groups are replaced by o-tolyl. It is often depicted as an azo structure, but according to X-ray crystallography closely related compounds exist as the keto-hydrazide tautomers.