Croconate blue

The term Croconate Blue as a dye name specifically refers to the dipotassium salt K2C14N6O2.

It hydrolyzes slowly in water to give croconic acid violet.

Extended heating in water produces deep green plates, apparently a polymer.

The dipotassium salt is obtained from the acid by treatment with potassium methoxide from water as a green-blue trihydrate, that slowly loses water converting to the dihydrate.

It quickly converts to croconate violet when treated with potassium hydroxide.