反应详情

To a chilled solution of (2-amino-4-cyanophenyl)-carbamic acid tert-butyl ester (2.1 g, 8.8 mmol) in CH2Cl2 (50 mL) and triethylamine (1.22 mL, 8.8 mmol) was added a solution of triphosgene (0.94 g, 3.2 mmol) in CH2Cl2 (50 mL) slowly. The reaction was stirred at room temperature for 3 hours, diluted with CH2Cl2, washed with water, brine, dried over Na2SO4, filtered and concentrated in vacuo. The residue was purified by flash chromatography in silica gel using a gradient from 30% to 60% ethyl acetate in n-heptane as eluent to afford 5-cyano-2-oxo-2,3-dihydro-benzoimidazole-1-carboxylic acid tert-butyl ester (1.7 g, 75%) as a white solid.

1. washwashed with water, brine
2. dry with materialdried over Na2SO4
3. filtrationfiltered
4. concentrationconcentrated in vacuo
5. customThe residue was purified by flash chromatography in silica gel using a gradient from 30% to 60% ethyl acetate in n-heptane as eluent