Nitric Acid → 4-Hydroxy-7,8-dimethyl-2H-1-benzopyran-2-one

Participants

Reaction Steps

Fuming nitric acid (16 ml) was added to a stirred suspension of 6-ethyl-4-hydroxy-7-methylcoumarin (m.p. 234°-7° ; 3.17g) in chloroform (250 ml) at room temperature over 1 hour. After standing for a further hour, the solvent was removed in vacuo at room temperature and 6N hydrochloric acid (60 ml) added to the residue. Filtration gave the product, m.p. 170°-2°(d), (C12H11NO5 requires C, 57.83; H, 4.45; N, 5.62. Found: C, 58.07; H, 4.54; N, 5.76).

Provenance & Evidence