Hydrogen Peroxide → 2-Amino-3-chloro-4-methoxybenzoic acid

A suspension of compound 246d (6.03 g, 28.52 mmol), NaOH (1.25 g, 31.37 mmol), and NaCl (3.49 g, 59.89 mmol) in water (60 mL) was stirred at room temperature for 30 min and was then ice-cooled. H2O2 was added dropwise. The mixture was stirred at 0° C. for 20 min and at room temperature for 3 hrs. The reaction mixture was quenched with glacial AcOH, filtered, and washed with water. The solid obtained was dissolved in DCM, dried over Na2SO4, filtered, and concentrated under reduced pressure. The crude material was purified by chromatography on silica gel (DCM/MeOH) to yield compound 247d as an orange solid in 36% yield. 1H NMR (DMSO-d6, 400 MHz) δ (ppm) 3.85 (s, 3H), 6.41 (d, J=9.05 Hz, 1H), 6.77 (brs, 2H), 7.74 (d, J=9.05 Hz, 1H), 12.7 (brs, 1H).

1. temperatureice-cooled
2. stirringThe mixture was stirred at 0° C. for 20 min and at room temperature for 3 hrs
3. customThe reaction mixture was quenched with glacial AcOH
4. filtrationfiltered
5. washwashed with water
6. customThe solid obtained
7. dry with materialdried over Na2SO4
8. filtrationfiltered
9. concentrationconcentrated under reduced pressure
10. customThe crude material was purified by chromatography on silica gel (DCM/MeOH)

ORD record

ord-c2ab589667be4fd093f0029a82445b61

Source dataset

uspto-grants-2013_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08377962B2