反应详情

2-Oxoindoline-5-carboxylic acid (0.214 g, 1.21 mmol), O-(benzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium tetrafluoroborate (0.462 g, 1.44 mmol), 1-hydroxybenzotriazole hydrate (0.194 g, 1.44 mmol) and N,N-diisopropylethylamine (0.3 mL, 1.71 mmol) were suspended in a mixture of acetonitrile (4 mL) and N,N-dimethylformamide (1 mL) and stirred at room temperature for 30 min. Benzylamine (0.155 g, 1.45 mmol) was added and stirring was continued for 12 h. The solvent was removed in vacuo and the residue was separated between chloroform and a saturated aqueous sodium hydrogen carbonate solution. The aqueous layer was extracted with chloroform (3×30 mL). The combined organic layers were dried over sodium sulfate. Filtration and removal of the solvent in vacuo yielded the crude product which was purified on a silica gel column using a gradient chloroform/methanol, (100:1 to 1:1), as the eluent to give 0.104 g (30% yield) of the title compound as a solid: 1H NMR (DMSO-d6, 400 MHz) δ 10.60 (s, 1H), 8.85 (m, 1H), 7.77 (m, 2H), 7.29 (m, 4H), 7.21 (m, 1H), 6.85 (d, J=11 Hz, 1H), 4.45 (d, J=6 Hz, 2H), 3.52 (s, 2H); MS (ES) m/z 267 (M++1).

1. stirringstirring
2. waitwas continued for 12 h
3. customThe solvent was removed in vacuo
4. customthe residue was separated between chloroform
5. extractionThe aqueous layer was extracted with chloroform (3×30 mL)
6. dry with materialThe combined organic layers were dried over sodium sulfate
7. filtrationFiltration and removal of the solvent in vacuo
8. customyielded the crude product which
9. customwas purified on a silica gel column