Hydrogen Bromide → Methyl 3-bromo-5-nitrobenzoate

To a mixture of methyl 3-amino-5-nitrobenzoate (2.5 g, 13 mmol) in 40% HBr (50 mL) was added drop-wise solution of sodium nitrite (1.1 g, 16 mmol) in water (5 mL) at 0° C. The mixture was stirred for 15 min and was then poured into a cold solution of copper (I) bromide (9.2 g, 65 mmol) in 40% HBr (50 mL). The resulting dark brown mixture was stirred for 30 min, and then was diluted with water and extracted with EtOAc (50 mL×3). The combined organic layers were washed with brine and water, dried over anhydrous Na2SO4, and concentrated under vacuum. The residue was purified by column chromatography on silica gel (5-10% ethyl acetate in petroleum ether) to afford methyl 3-bromo-5-nitrobenzoate (2.2 g, 67% yield). 1H NMR (400 MHz, CDCl3) δ 8.79 (dd, J=1.6, 2.0 Hz, 1H), 8.55 (t, J=1.6 Hz, 1H), 8.49 (t, J=1.6 Hz, 1H), 4.00 (s, 3H).

1. stirringThe resulting dark brown mixture was stirred for 30 min
2. extractionextracted with EtOAc (50 mL×3)
3. washThe combined organic layers were washed with brine and water
4. dry with materialdried over anhydrous Na2SO4
5. concentrationconcentrated under vacuum
6. customThe residue was purified by column chromatography on silica gel (5-10% ethyl acetate in petroleum ether)

ORD record

ord-efb23b9a63c14f89997b8875b131810c

Source dataset

uspto-grants-2011_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07956052B2