Acetic Anhydride → 3-Methylbenzo[d]isoxazole

Participants

Reaction Conditions

Reaction Steps

Acetic anhydride (7.1 mL, 75 mmol) was added to 24 (7.55 g, 50 mmol) in a 100 mL flask. The mixture was heated to 60° C. for 3 hours followed by evaporation to dryness. Potassium carbonate (8.7 g, 63 mmol) was partly dissolved in 40 mL DMF and added to the mixture. The mixture was stirred at room temperature overnight and finally heated to 100° C. for 30 minutes. Ethyl acetate and water were added. The phases were separated and the aqueous phase was extracted with ethyl acetate and dichloromethane. The combined organic phases were dried over magnesium sulphate and evaporated to dryness to give 5.6 g of a yellow oil. Crude product was purified by column chromatography (100% dichloromethane), producing pure 25 (4.6 g). 1H NMR (CDCl3) δ 2.6 (s, 3H), 7.3 (m, 1H), 7.55 (m, 2H), 7.65 (m, 1H).

Provenance & Evidence