Aluminum(III) Chloride → 5-Hydroxy-1H-benzo[d][1,3]oxazine-2,4-dione

Participants

Reaction Steps

A suspension of Example 385A (1.93 g, 10 mmol) in dichloromethane (100 mL) was treated with AlCl3 (2.6 g, 20 mmol), stirred at room temperature overnight, treated slowly with brine (100 mL) while vigorously stirring, and extracted with ethyl acetate. The desired product was obtained as a white solid after evaporation of the solvent. Yield: 1.74 g, 97.2%. 1H NMR (DMSO-d6) δ 6.55 (d, 1H), 6.65 (d, 1H), 7.50 (t, 1H), 10.35 (s, 1H), 11.62 (br s, 1H); MS (ESI(−)) m/e 178 (M−H)−.

Provenance & Evidence