反应详情

温度

0 °C

3.0 g (12.1 mmol) of the compound from Example 5A were initially charged in 30 ml of dichloromethane, cooled to 0° C. and admixed with 3.4 ml (2.4 g, 12.1 mmol) of triethylamine and 2.4 g (12.1 mmol) of 4-nitrophenyl chloroformate. The reaction mixture was allowed to warm up slowly to RT and stirred at RT for 16 h. The mixture was washed several times with water, dried over sodium sulphate, filtered and concentrated under reduced pressure. The residue was purified by column chromatography on silica gel (eluent dichloromethane→dichloromethane/methanol 100:2). Yield: 4.7 g (83% of theory, purity 89%)

1. temperatureto warm up slowly to RT
2. washThe mixture was washed several times with water
3. dry with materialdried over sodium sulphate
4. filtrationfiltered
5. concentrationconcentrated under reduced pressure
6. customThe residue was purified by column chromatography on silica gel (eluent dichloromethane→dichloromethane/methanol 100:2)