反应详情

A mixture of Example 679A (204 mg, 0.8 mmol), trifluoroacetic acid (0.87 mL, 8 mmol), and triethylsilane (1.27 mL, 8 mmol) in methylene chloride was stirred at room temperature for 5 days. The solution was concentrated under vacuum, diluted with methylene chloride, and poured into 2M NaOH. The organic layer was washed with brine, dried (MgSO4), filtered, and concentrated under vacuum. The residue was then purified by flash column chromatography on silica gel with 1:1 hexanes/methylene chloride to provide 108 mg (57%) of the title compound. MS (ESI) m/e 240 (M+H)+, 1H NMR (DMSO-d6, 300 MHz): □ 8.88 (s, 1H), 7.67 (s, 1H), 7.21 (d, J=7.80 Hz, 1H), 7.07 (d, J=2.03 Hz, 1H), 6.96 (dd, J=7.80, 2.03 Hz, 1H), 4.10 (s, 2H), 3.84 (s, 3H).

1. concentrationThe solution was concentrated under vacuum
2. additiondiluted with methylene chloride
3. additionpoured into 2M NaOH
4. washThe organic layer was washed with brine
5. dry with materialdried (MgSO4)
6. filtrationfiltered
7. concentrationconcentrated under vacuum
8. customThe residue was then purified by flash column chromatography on silica gel with 1:1 hexanes/methylene chloride