Chemistry of indanthrone. Part XII. Some properties of the dinaphthophenazinediquinones and their NN′-dihydro-derivatives

Abstract

The preparations of three dinaphthophenazinediquinones are described, and a comparison of their properties made, in particular their dehydrogenating action on alcohols. The degradative oxidation of 7,16-dihydrodinaphtho-[2,3-b:2′,3′-i]phenazine-5,9,14,18-diquinone (A) with chromium trioxide in acetic acid afforded 2,3-dihydroxynaphtho[2,3-g]quinoxaline-6,11-quinone and its chromium salt. The N-methylation of (A) using methyl toluene-p-sulphonate, and the properties of the derived 7,16-dimethyl derivative are described. Bromination of (A) in nitrobenzene gave the 6-bromo-derivative, some reactions of which are given.