反应详情

A mixture of [2-(3,5-dibromo-4-nitropyrazol-1-yl)ethyl]carbamic acid tert-butyl ester (3.5 g; 8.45 mmol), EtOH (100 ml) and benzylamine (12.9 g, 117 mmol) was heated at reflux for 1.5 h. The reaction medium was concentrated as much as possible under reduced pressure. The residue was taken up in DCM (100 ml) and the organic phase was washed with water (5×50 ml) until all excess benzylamine had been removed and was then dried over Na2SO4. The organic solvent was evaporated under reduced pressure to give the [2-(5-benzylamino-3-bromo-4-nitropyrazol-1-yl)ethyl]carbamic acid tert-butyl ester (2.5 g, 67%) in the form of a pale yellow solid.

1. temperaturewas heated
2. temperatureat reflux for 1.5 h
3. concentrationThe reaction medium was concentrated as much as possible under reduced pressure
4. washthe organic phase was washed with water (5×50 ml) until all excess benzylamine
5. customhad been removed
6. dry with materialwas then dried over Na2SO4
7. customThe organic solvent was evaporated under reduced pressure