Collect. Czech. Chem. Commun. 1988, 53, 1574-1578

An intermediate of reaction of 2-naphthol with activated sludge

Karel Komersa, Antonín Lyčkab, Josef Jirmanb and Ivan Kolbb

a Department of Physical Chemistry, Institute of Chemical Technology, 532 10 Pardubice
b Research Institute of Organic Syntheses, 532 18 Pardubice-Rybitví


A redbrown intermediate has been isolated from a reaction mixture of 2-naphthol and the activated sludge, and its structure has been determined on the basis of its IR, MS, and especially 2D 1H and 13C NMR spectra. It corresponds to 4-(2-hydroxy-1-naphthyl)-6-hydroxy-1,2-naphthoquinone (I). In aqueous media I behaves as an acid-base indicator with the colour transition from yellow to redbrown. The concentration dissociation constants of I have been determined spectrophotometrically: K1 = 3·47 . 10-7, K2 = 3·80 . 10-10 for the standard state c0 = 1 mol dm-3, 298 K, 105 Pa.