1,3-Dibromobenzene → 2,4-Dibromo-1-nitrobenzene

Temperature

0 °C

To an ice-cold solution of 1,3-dibromobenzene (10 g, 42.4 mmol) in concentrated sulfuric acid (200 mL) was added ammonium nitrate (3.39 g, 42.4 mmol) portionwise. The reaction mixture was stirred at 0° C. for 15 min, then it was poured onto an ice-water mixture. The aqueous mixture was extracted with dichloromethane (2×). The combined organic layers were washed with water then a saturated aqueous solution of sodium bicarbonate (2×), dried over sodium sulfate, filtered, and concentrated in vacuo. The residue was triturated with hexane, filtered, and dried in vacuo to give 7.63 g of 2,4-dibromo-1-nitro-benzene as a yellow solid (64% yield): 1H NMR (CDCl3) δ 7.62 (dd, 1H), 7.78 (d, 1H), 7.95 (d, 1H).

1. extractionThe aqueous mixture was extracted with dichloromethane (2×)
2. washThe combined organic layers were washed with water
3. dry with materiala saturated aqueous solution of sodium bicarbonate (2×), dried over sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. customThe residue was triturated with hexane
7. filtrationfiltered
8. customdried in vacuo

ORD record

ord-65d451a2e4634fe89d129006086d426f

Source dataset

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08507489B2