反应详情

A solution of 5-fluoro-1H-indole (16.9 mmol) and potassium tert-butoxide (33.8 mmol) in DMF (76 mL) is stirred at rt under N2 for 2 h. 0.15 M NH2Cl. in ether (169.2 mL) is added drop-wise for 15 minutes at rt. The reaction mixture is stirred at rt for 2 h, then quenched with 10% Na2S2O3 aqueous solution and extracted with ether. The organic layer is separated, dried (Na2SO4), filtered and concentrated in vacuo. The residue is purified by silica gel chromatography eluting with 60-80% EtOAc in heptane to afford 5-fluoro-indole-1-ylamine (751 mg, 30%) as a solid. 1H NMR (300 MHz, CDCl3): δ 4.80 (br, 2N—H), 6.38 (d, H), 7.00 (m, H), 7.19-7.43 (m, 3H).

1. customquenched with 10% Na2S2O3 aqueous solution
2. extractionextracted with ether
3. customThe organic layer is separated
4. dry with materialdried (Na2SO4)
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customThe residue is purified by silica gel chromatography
8. washeluting with 60-80% EtOAc in heptane