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

Participants

Reaction Steps

Fuming nitric acid (18 ml) was added to a stirred suspension of 4-hydroxy-5,6,7-trimethylcoumarin (m.p. 262°-4°; 3.38g) in chloroform (250 ml) at room temperature over 1.5 hours. After a further 30 minutes, the solvent was removed in vacuo at room temperature and 6N hydrochloric acid (70 ml) added to the residue. Filtration gave the product, m.p. 134°-7°(d), (C12H11NO5 requires C, 57.83; H, 4.45; N, 5.62. Found: C, 57.92; H, 4.57; N, 5.65).

Provenance & Evidence