反应详情

A stirred mixture of 1.0 g (4 mmol) of ethyl 3H-furo[2,3-f]benzoxazole-2-one-6-carboxylate, 100 ml of ethanol and 0.5 g of potassium hydroxide is refluxed for 1 h. The mixture is concentrated, the residue is dissolved in water and acidified with 20% aqueous sulfuric acid solution. The precipitated crystals are filtered off and washed with water to yield 0.84 g (95%) of the title compound. Mp.: 190-192° C. (water).

1. temperatureis refluxed for 1 h
2. concentrationThe mixture is concentrated
3. dissolutionthe residue is dissolved in water
4. filtrationThe precipitated crystals are filtered off
5. washwashed with water