反应详情

A mixture of 913 mg (5.46 mmol) 3-amino-2-hydroxy-benzoic acid methyl ester, 894 mg (8.19 mmol) of cyanogen bromide, 14.4 mL of ethanol and 1.6 mL of water was heated under reflux for 1 h. Ethanol was evaporated under reduced pressure and 20 mL of 2 N aq. Na2CO3 was added to the residue. The precipitated solid was filtered and washed with water. The remaining product was treated with methanol and the soluble filtrate containing the product was evaporated in vacuo to provide 797 mg (4.15 mmol, 76%) of 2-amino-benzooxazole-7-carboxylic acid methyl ester. LCMS: 193 (M+1)+.

1. temperaturewas heated
2. temperatureunder reflux for 1 h
3. customEthanol was evaporated under reduced pressure and 20 mL of 2 N aq. Na2CO3
4. additionwas added to the residue
5. filtrationThe precipitated solid was filtered
6. washwashed with water
7. additionThe remaining product was treated with methanol
8. additionthe soluble filtrate containing the product
9. customwas evaporated in vacuo