Why schiff`s reagent doesnot react with aromatic ketone ??

Schiff's reagent A reagent utilized for testing for aldehydes and ketones; it comprises of an answer of fuchsin color that has been decolorized by sulfur dioxide. Aliphatic aldehydes reestablish the pink promptly, while sweet-smelling ketones have no impact on the reagent. Fragrant aldehydes and aliphatic ketones reestablish the shading gradually as the aldehyde really associates with the - NH2SO2H there are 3 destinations on the reagent where as the ketones does not interface