Dichloromethane → 2-Bromo-5-nitrophenol

Temperature

-44 °C

A mixture of 29.1 g (125.6 mmol) of 2-bromo-5-nitroanisole and 250 mL CH2Cl2 was stirred at −44° C. in a dry ice acetonitrile bath under a nitrogen atmosphere. Boron tribromide (18 mL) was added dropwise to the reaction mixture. The resulting black reaction was stirred while allowing the cooling bath to slowly rise to room temperature over 20 h. TLC analysis indicated complete reaction, so the reaction mixture was transferred to an addition funnel and added cautiously to a mixture of ice, water and 75 g solid KH2PO4. The layers were separated, the aqueous layer was washed with CH2Cl2, the combined organic extracts were washed with brine, dried over anhydrous magnesium sulfate, filtered, concentrated to give 27.4 g (125.6 mmol, 100%) of 2-bromo-5-nitrophenol as a black solid. 1H NMR (400 MHz) CDCl3 7.85 (s, 1H), 7.62-7.70 (m, 2H), 5.88 (s, 1H).

1. customThe resulting black reaction
2. stirringwas stirred
3. customreaction
4. customso the reaction mixture was transferred to an addition funnel
5. customThe layers were separated
6. washthe aqueous layer was washed with CH2Cl2
7. washthe combined organic extracts were washed with brine
8. dry with materialdried over anhydrous magnesium sulfate
9. filtrationfiltered
10. concentrationconcentrated

ORD record

ord-5ffed445314d4b5e92fbcd8e0079d338

Source dataset

uspto-grants-2005_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06875765B2