Bohn-Schmidt Reaction

R. Bohn, DE 46654 (1889); R. E. Schmidt, DE 60855 (1891).

Hydroxylation of anthraquinones containing at least one hydroxyl group by treatment with fuming sulfuric acid or sulfuric acid and boric acid in the presence of a catalyst such as mercury:

Reviews: M. Phillips, Chem. Rev. 6, 168 (1929); Fieser, Fieser, Organic Chemistry (New York, 1956) p 903. Studies and proposed mechanism: J. Winkler, W. Jenny, Helv. Chim. Acta 48, 119 (1965); B. R. Dhruva et al., Indian J. Chem. 14 (B), 622 (1976).