Acetic Acid → HCID 178526878, compound

Participants

Reaction Conditions

Reaction Steps

86% phosporic acid (90 mL, 151.3 g) and 3-cyano-4-methoxy-2(1H)-pyridinone (Compound X) (30.0 g, 0.20 mole) are combined under argon in a 500 mL flask equipped with a mechanical stirrer, reflux condensor. The mixture is heated in an oil bath at 175-180° C. for 23 hours. The reaction mixture is cooled to 71° C. and glacial acetic acid (90 mL, 94.5 g) added and the mixture heated at 90° C. for about 90 minutes. Fuming nitric acid (density=1.52) (12.6 g, 8.3 ml) is then added carefully over a period of 15 minutes (giving a mild exotherm), and the mixture heated at 90-95° C. for 2 hours. Water (90 mL) is then added to the mixture and heating at 90° C. continued for 1 hour. The mixture is then cooled slowly with stirring to room temperature, filtered through a sintered glass funnel and the residue washed with water to give Compound XII, m.p. 268° C.; NMR (DMSO) δ 7.44 (1H, d); 6.0 (1H, d); 3.5 (2H).

Provenance & Evidence