1,3-Dinitrobenzene → Tert-butyl 4-(3-fluoro-4-nitrophenyl)piperazine-1-carboxylate

Temperature

50 °C

2,4-dinitrobenzene (1.2 g), N-Boc-piperazine (1.4 g) and potassium carbonate (1.2 g) were dissolved in dimethylformamide (5 mL) and stirred at 50° C. overnight. Then, the mixture was distilled under reduced pressure to remove dimethylformamide, added with water, and extracted with ethyl acetate. The thus obtained organic layer was washed with brine, and water was removed with sodium sulfate, and the solvent was removed by distillation under reduced pressure. The mixture was purified by column chromatography (silica gel) to obtain target compounds (Rf=0.3, hexane:ethyl acetate=2:1) and (tert-butyl-4-(5-fluoro-2-nitrophenyl)piperazin-1-carboxylate (Rf=0.6, hexane:ethyl acetate=2:1).

1. distillationThen, the mixture was distilled under reduced pressure
2. customto remove dimethylformamide
3. additionadded with water
4. extractionextracted with ethyl acetate
5. washThe thus obtained organic layer was washed with brine, and water
6. customwas removed with sodium sulfate
7. customthe solvent was removed by distillation under reduced pressure
8. customThe mixture was purified by column chromatography (silica gel)
9. customto obtain target compounds (Rf=0.3, hexane:ethyl acetate=2:1)

ORD record

ord-33434855225a4960ab79bee64b09fab3

Source dataset

uspto-grants-2015_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09199944B2