反应详情

To 7 g 4-Bromo-1H-indole-2-carboxylic acid in 150 ml toluene, 28 ml Di-tert-butoxymethyl-dimethyl-amine were added dropwise at 80° C. The reaction mixture was heated under reflux for additional 12 h. After removal of the solvents under reduced pressure the residue was dissolved in 200 ml DCM and washed with sat. aqueous NaHCO3 solution (2×50 ml). The organic layer was dried over MgSO4 and concentrated under reduced pressure. The residue was purified by chromatography on silica gel eluting with n-heptane/ethyl acetate 9:1. The fractions containing the product were collected and concentrated under reduced pressure. Yield: 6.5 g . MS (ESI+): m/e=297.

1. temperatureThe reaction mixture was heated
2. temperatureunder reflux for additional 12 h
3. customAfter removal of the solvents under reduced pressure the residue
4. dissolutionwas dissolved in 200 ml DCM
5. washwashed with sat. aqueous NaHCO3 solution (2×50 ml)
6. dry with materialThe organic layer was dried over MgSO4
7. concentrationconcentrated under reduced pressure
8. customThe residue was purified by chromatography on silica gel eluting with n-heptane/ethyl acetate 9:1
9. additionThe fractions containing the product
10. customwere collected
11. concentrationconcentrated under reduced pressure