反应详情

To a suspension of 2-amino-3-nitro benzoic acid (2.12 g, 10 mmol) in benzene (75 mL) was added dropwise thionyl chloride (1.8 mL, 25 mmol). The suspension was heated to reflux overnight. The mixture was cooled to room temperature and concentrated under reduced pressure to afford a golden solid. The crude material was dissolved in THF (40 mL) and cooled in an ice bath. Sodium borohydride (0.83 g, 22 mmol) was added in portions, and the reaction was allowed to come to room temperature with stirring. The ice bath was replaced and H2O (15 mL) was slowly added to the reaction. Once gas evolution had subsided, the solution was concentrated under reduced pressure. The residue was dissolved in EtOAc (200 mL) and washed with NaHCO3 (2×50 mL) and brine (50 mL). The organic layer was dried (Na2SO4), filtered, and concentrated under reduced pressure. The reside was adsorbed onto silica gel and purified by column chromatography, eluting with a gradient of 25% EtOAc/hexane to 50% EtOAc/hexane to afford the alcohol (0.89 g, 46%) as an orange solid. mp: 100° C. 1H NMR 300 MHz (DMSO-d6): δ=7.92 (dd, 1H, J=8.7, 1.4 Hz), 7.49 (d, 1H, J=6.8 Hz), 7.12 (bs, 2H), 6.66 (dd, 1H, J=8.7, 7.1 Hz), 5.45 (t, 1H, J=5.4 Hz), 4.52 (d, 2H, J=5.4 Hz). MS (ESI-POS): [M+H]+=169.

1. temperatureThe suspension was heated
2. temperatureto reflux overnight
3. concentrationconcentrated under reduced pressure
4. customto afford a golden solid
5. temperaturecooled in an ice bath
6. customto come to room temperature
7. concentrationthe solution was concentrated under reduced pressure
8. dissolutionThe residue was dissolved in EtOAc (200 mL)
9. washwashed with NaHCO3 (2×50 mL) and brine (50 mL)
10. dry with materialThe organic layer was dried (Na2SO4)
11. filtrationfiltered
12. concentrationconcentrated under reduced pressure
13. custompurified by column chromatography
14. washeluting with a gradient of 25% EtOAc/hexane to 50% EtOAc/hexane