反应详情

To a solution of (±)-methyl (4-nitro-2,3-dihydro-1H-indol-3-yl)acetate from Step B (700 mg, 2.97 mmol), sodium carbonate (471 mg, 4.44 mmol), and potassium iodide (98 mg, 0.59 mmol) in acetone (15 mL) was added ethyl bromoacetate (9.9 mL, 88.9 mmol). The mixture was heated at reflux for 18 h, then cooled to ambient temperature and concentrated in vacuo. The residue was partitioned between H2O (15 mL) and EtOAc (2×40 mL) and the organic extracts were washed with brine, dried over Na2SO4, filtered, and concentrated in vacuo to a volume of 50 mL. Hexane was added to the EtOAc solution and a precipitate formed. The desired crystals were collected by vacuum filtration to give the title compound. MS: m/z=323 (M+1).

1. temperatureThe mixture was heated
2. temperatureat reflux for 18 h
3. concentrationconcentrated in vacuo
4. customThe residue was partitioned between H2O (15 mL) and EtOAc (2×40 mL)
5. washthe organic extracts were washed with brine
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo to a volume of 50 mL
9. additionHexane was added to the EtOAc solution
10. customa precipitate formed
11. filtrationThe desired crystals were collected by vacuum filtration