Sulfuric Acid → 2-Bromo-6-nitrophenol

A solution of 60 mL of concentrated sulfuric acid diluted with 186 mL of water was cooled to room temperature. Sodium nitrate (79.2 g, 0.93 mol) was added to the solution. 2-Bromo-phenol 1a (60 mL, 0.52 mol) was added dropwise at such a rate that the reaction temperature was kept below 25° C. The reaction mixture was stirred at room temperature for 2 hours. The precipitate was dissolved in 320 mL of ethyl acetate. The mixture was washed with water and saturated brine, dried over anhydrous magnesium sulfate, filtered and the filtrate was concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography to obtain the title compound 2-bromo-6-nitro-phenol 1b (48.2 g, yield 42.8%) as a yellow solid.

1. customwas kept below 25° C
2. washThe mixture was washed with water and saturated brine
3. dry with materialdried over anhydrous magnesium sulfate
4. filtrationfiltered
5. concentrationthe filtrate was concentrated under reduced pressure
6. customThe resulting residue was purified by silica gel column chromatography

ORD-Eintrag

ord-48bd4bb188e9472bb4d9c1e808ff3e49

Quelldatensatz

uspto-grants-2014_02

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08642637B2