反应详情

温度

80 °C

Place 2,3-dichloro-5-nitro-pyridine (2.0 g, 10.36 mmol), piperazine-1-carboxylic acid tert-butyl ester (2.12 g, 11.40 mmol), and potassium carbonate (1.72 g, 12.43 mmol) in DMF (20 mL). Heat to 80° C. for 2.5 days. Cool to room temperature and add ethyl acetate and water. Separate organic layer and wash with water and saturated aq. sodium chloride. Collect organic layer, dry over Mg2SO4, filter, and concentrate under reduced pressure. Subject residue to silica gel chromatography eluting with 20% EtOAc:hexane to yield 3.29 g (93%) of 4-(3-chloro-5-nitro-pyridin-2-yl)-piperazine-1-carboxylic acid tert-butyl ester. MS(ES): m/z=341 [M+H].

1. temperatureCool to room temperature
2. washSeparate organic layer and wash with water and saturated aq. sodium chloride
3. dry with materialCollect organic layer, dry over Mg2SO4
4. filtrationfilter
5. concentrationconcentrate under reduced pressure
6. washSubject residue to silica gel chromatography eluting with 20% EtOAc