Ethyl Acetate → 2,5-Dibromo-3,6-difluoroaniline

Temperatur

80 °C

2,5-Dibromo-3,6-difluoronitrobenzene (120 g, 0.37 mol) is dissolved in a mixture of ethanol (300 mL) and concentrated HCl (500 mL). The mixture is heated to 80° C. and treated with iron powder (100 g, 1.78 mol) by portion-wise addition over 2 hours. After stirring for an additional hour, the mixture is cooled to room temperature and EtOAc (800 mL) is added. The solids are removed by filtration and then the solution concentrated by rotary evaporator to remove most of the solvent. The residue is partitioned between EtOAc (1000 mL) and water (500 mL). The organic layer is washed with brine (2×250 mL), dried (MgSO4) and concentrated by rotary evaporator to give a brown oil. The crude product is then purified using flash chromatography (9:1 hexanes/EtOAc) to give 2,5-dibromo-3,6-difluoroaniline.

1. temperaturethe mixture is cooled to room temperature
2. customThe solids are removed by filtration
3. concentrationthe solution concentrated by rotary evaporator
4. customto remove most of the solvent
5. customThe residue is partitioned between EtOAc (1000 mL) and water (500 mL)
6. washThe organic layer is washed with brine (2×250 mL)
7. dry with materialdried (MgSO4)
8. concentrationconcentrated by rotary evaporator
9. customto give a brown oil
10. customThe crude product is then purified

ORD-Eintrag

ord-7cf0a0c661de42a19af0ec90263fae5f

Quelldatensatz

uspto-grants-2007_04

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07202364B2