Hydrochloric Acid → 4-Amino-2-bromo-3-methylbenzaldehyde

Temperature

90 °C

To a solution of commercially available 3-bromo-2-methyl-phenylamine (1.86 g, 10 mmol) in DMSO (200 mL) was added concentrated HCl (10 mL), followed by CuCl2 (2.7 g, 20 mmol). The resulting suspension was heated to 90° C. for 6 h. After cooling to rt, the reaction mixture was poured into ice/water (600 mL) and adjusted to pH=8 by dropwise addition of 10% aqueous NaOH. The resulting greenish suspension was filtered through a pad of Celite®, and the filtrate extracted with ether (3×). The combined organics were washed with brine, dried (Na2SO4), filtered and concentrated. The residue was chromatographed (silica gel), eluting with 30-70% EtOAc/hexane to furnish the title compound (0.67 g, 31%).

1. temperatureAfter cooling to rt
2. filtrationThe resulting greenish suspension was filtered through a pad of Celite®
3. extractionthe filtrate extracted with ether (3×)
4. washThe combined organics were washed with brine
5. dry with materialdried (Na2SO4)
6. filtrationfiltered
7. concentrationconcentrated
8. customThe residue was chromatographed (silica gel)
9. washeluting with 30-70% EtOAc/hexane

ORD record

ord-f81d830fb45f44d8981b257cfb04434d

Source dataset

uspto-grants-2008_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07405234B2