Acidities of anthraquinone and its hydroxy derivatives

The acidities of anthraquinone and its 1- and 6-hydroxy derivatives were studied. It is shown that the anthrone ring in the anthrapyridone molecule displays a strong electron-acceptor effect that stabilizes the anion during the development in the pyridone ring of a negative charge as a result of ionization; as a consequence of this, anthrapyridone and 1-hydroxyanthrapyridone are considerably stronger acids than 2-pyridone and 3-hydroxy-2-pyridone, respectively.Communication VII from the series Structure and Properties of Dyes. See [1] for communication VI.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1373–1376, October, 1978.