反应详情

To a solution of tert-butyl 4-(1-ethylpropyl)-3-(2-isopropoxy-2-oxoethyl)-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxylate (8.95 g, 22.1 mmol) in ethyl acetate (10 ml) was added a 4N solution of hydrogen chloride in ethyl acetate (20 ml), and the mixture was stirred at room temperature for 1 hour. The reaction mixture was diluted with saturated aqueous sodium hydrogen carbonate and extracted with ethyl acetate (X2). The combined organic layer was washed with brine (X1), dried over sodium sulfate and concentrated in vacuo. The residue was purified by silica gel column chromatography eluting with a 5-20% ethyl acetate/hexane gradient mixture. The residual solid was washed with hexane to give 5.76 g (18.9 mmol, 85.6%) of the title compound as a colorless solid.

1. extractionextracted with ethyl acetate (X2)
2. washThe combined organic layer was washed with brine (X1)
3. dry with materialdried over sodium sulfate
4. concentrationconcentrated in vacuo
5. customThe residue was purified by silica gel column chromatography
6. washeluting with a 5-20% ethyl acetate/hexane gradient mixture
7. washThe residual solid was washed with hexane