反应详情

A mixture of methyl 2,3-diamino-5-(4-morpholinyl)benzoate (4.0 g) in CF3COOH (20 mL) was heated at reflux temperature for 8 h. When TLC analysis indicated consumption of starting material, the mixture was cooled to room temperature and the solvent was removed in-vacuo. The residue was diluted with aqueous NaHCO3 and extracted with EtOAc (250 mL×3). The combined organic layers were washed with brine (250 mL×2), dried over anhydrous Na2SO4. After filtration, the solvent was removed by rotary evaporator. The residue was then purified by silica gel chromatography eluted with EtOAc:petroleum ether=1:4 to afford the desired product as a pale solid. (4.3 g, 82.7%). 1H NMR (300 MHz, DMSO-d6): δ ppm 13.47 (s, 1H), 7.71 (s, 1H), 7.56 (s, 1H), 3.96 (s, 3H), 3.79 (t, 4H, J=4.5 Hz), 3.17 (s, 4H). LC-MS: m/e=330.1 [M+1]+.

1. temperaturewas heated
2. temperatureat reflux temperature for 8 h
3. customconsumption of starting material
4. customthe solvent was removed in-vacuo
5. additionThe residue was diluted with aqueous NaHCO3
6. extractionextracted with EtOAc (250 mL×3)
7. washThe combined organic layers were washed with brine (250 mL×2)
8. dry with materialdried over anhydrous Na2SO4
9. filtrationAfter filtration
10. customthe solvent was removed by rotary evaporator
11. customThe residue was then purified by silica gel chromatography
12. washeluted with EtOAc