反应详情

温度

-78 °C

To acetic anhydride (5 mL) at 0° C. was added 90% nitric acid (0.183 mL, 3.90 mmol) and the resulting mixture was aged for 10 min, then added dropwise to a solution of tert-butyl [1-(phenylsulfonyl)-1H-indol-4-yl]acetate from Step B (1.00 g, 2.69 mmol) in acetic anhydride (5 mL) at −78° C. The reaction mixture was stirred at −78° C. for 6 h, then aged at −20° C. for 16 b, then quenched with H2O and extracted with EtOAc (2×10 mL). The combined organic extracts were dried over Na2SO4, filtered, and concentrated in vacuo. The crude product was purified by silica gel chromatography, eluting with a gradient of hexane:EtOAc—100:0 to 70:30, to give the title compound. MS: m/z=361 (M−C4H7).

1. customaged at −20° C. for 16 b
2. customquenched with H2O
3. extractionextracted with EtOAc (2×10 mL)
4. dry with materialThe combined organic extracts were dried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customThe crude product was purified by silica gel chromatography
8. washeluting with a gradient of hexane