反应详情

A suspension of 5-bromo-2-methoxyphenylboronic acid (500 mg, 2.17 mmol), 3-iodonitrobenzene (647 mg, 2.60 mmol), and potassium carbonate (599 mg, 4.33 mmol) in methanol (10 mL) and water (2 mL) was degassed for 30 min under a nitrogen stream followed by the addition of palladium(II) acetate (9.72 mg, 0.0433 mmol). The reaction was stirred at room temperature for 4 h. The methanol was removed under reduced pressure, ethyl acetate (50 mL) and water (50 mL) were added, and the biphasic suspension was filtered. The layers were separated and the organic was washed with water (50 mL). The aqueous washes were combined and extracted with ethyl acetate (2×50 mL), and the organic extracts combined. The organic solution was washed with water (3×50 mL), saturated aqueous sodium bicarbonate (50 mL), brine, dried over sodium sulfate, filtered, and the solvent removed under vacuum to give a crude brown gum. The product was purified by flash silica gel column chromatography (5% ethyl acetate in hexanes), and crystallized by dissolving in diethyl ether (20 mL) and hexanes (50 mL), removing one half of the solvent under vacuum, filtering and washing with hexanes (2×10 mL) to give I-207 (417.8 mg, 63% yield). 1H NMR (400 MHz, CDCl3) 8.38 (t, J=1.8 Hz, 1H), 8.21-8.19 (m, 1H), 7.81 (dt, J=7.5 Hz, 1.3 Hz, 1H), 7.58 (t, J=8.0 Hz, 1H), 7.50-7.45 (m, 2H), 6.90 (d, J=8.8 Hz, 1H), 3.82 (s, 3H) ppm.

1. customwas degassed for 30 min under a nitrogen stream
2. customThe methanol was removed under reduced pressure, ethyl acetate (50 mL) and water (50 mL)
3. additionwere added
4. filtrationthe biphasic suspension was filtered
5. customThe layers were separated
6. washthe organic was washed with water (50 mL)
7. extractionextracted with ethyl acetate (2×50 mL)
8. washThe organic solution was washed with water (3×50 mL), saturated aqueous sodium bicarbonate (50 mL), brine
9. dry with materialdried over sodium sulfate
10. filtrationfiltered
11. customthe solvent removed under vacuum
12. customto give a crude brown gum
13. customThe product was purified by flash silica gel column chromatography (5% ethyl acetate in hexanes)
14. customcrystallized
15. dissolutionby dissolving in diethyl ether (20 mL)
16. customhexanes (50 mL), removing one half of the solvent under vacuum
17. filtrationfiltering
18. washwashing with hexanes (2×10 mL)
19. customto give I-207 (417.8 mg, 63% yield)