Nitric Acid → 1-Bromo-2-fluoro-3,5-dinitrobenzene

Temperature

80 °C

To 1-fluoro-2,4-dinitrobenzene (13.0 g, 69.85 mmol, 1 equiv) dissolved in sulfuric acid (190 mL) at room temperature was added bromine (4.30 mL, 83.82 mmol, 1.2 equiv) dropwise followed by the slow dropwise addition of nitric acid (70%, d=1.500; 3.25 mL, 76.84 mmol, 1.1 equiv). The reaction vessel was fitted with a refluxing condenser, and the reaction mixture was heated at 80° C. for 10 hours. LCMS indicated a reactant:product ratio of 1:1. After allowing to cool to room temperature, the mixture was poured into ice and diluted with DCM. The aqueous and organic layers were partitioned, and the aqueous extracted with DCM (2×300 mL). The combined organic extracts were washed with saturated Na2S2O3 (2×200 mL), dried (Na2SO4), filtered, and concentrated to dryness. The crude product was purified using a pad of silica gel and eluted with EtOAc/hexanes (25-35% EtOAc in increments of 5% EtOAc) to give the product 1-bromo-2-fluoro-3,5-dinitrobenzene (5.55 g, 30%) as a light-yellow solid.

1. customThe reaction vessel was fitted with a refluxing condenser
2. temperatureto cool to room temperature
3. additionthe mixture was poured into ice
4. customThe aqueous and organic layers were partitioned
5. extractionthe aqueous extracted with DCM (2×300 mL)
6. washThe combined organic extracts were washed with saturated Na2S2O3 (2×200 mL)
7. dry with materialdried (Na2SO4)
8. filtrationfiltered
9. concentrationconcentrated to dryness
10. customThe crude product was purified
11. washeluted with EtOAc/hexanes (25-35% EtOAc in increments of 5% EtOAc)

ORD record

ord-457cac3397074dc4be8a2f6b342f7a27

Source dataset

uspto-grants-2015_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09181222B2