Near uv irradiation of anthracene-9, 10-dione in deoxygenated 96% H2SO4 generates the sulphate ester of 2-hydroxyanthracene-9, 10-dione in high yield along with the 1-hydroxy isomer and the novel reduction products anthracen-9 (10H)-one and 9, 9′-bianthracene- 10, 10′(9H, 9′ H)-dione; contrary to previous results, the product distribution and the rate of reaction are dependent upon the concentration of O2 in the solution.
