1,3-Dichloro-2-fluoro-5-nitrobenzene → 3,5-Dichloro-4-fluoroaniline

To a solution of 1,3-dichloro-2-fluoro-5-nitro-benzene (71.4 g, 340 mmol) in methanol (1.5 L) was added a solution of ammonium formate (180.2 g, 2.86 mol) in water (300 mL). Zinc dust (93.4 g, 1.43 mol) was then added in four equal portions over 20 min. The reaction was stirred for 1 h and then allowed to cool to room temperature. The reaction mixture was filtered through diatomaceous earth and the filtrate was concentrated in vacuo. Ethyl acetate (300 mL) and water (300 mL) were added and the mixture was again filtered through diatomaceous earth. The layers were separated, and the aqueous layer was further extracted with ethyl acetate (350 mL). The combined organics were washed with 500 mL of brine, dried over Na2SO4, filtered, and concentrated to afford 56.4 g of the title compound as a brown solid, m/z 180.2 [M+H]+. This material was used without any further purification.

1. filtrationThe reaction mixture was filtered through diatomaceous earth
2. concentrationthe filtrate was concentrated in vacuo
3. additionEthyl acetate (300 mL) and water (300 mL) were added
4. filtrationthe mixture was again filtered through diatomaceous earth
5. customThe layers were separated
6. extractionthe aqueous layer was further extracted with ethyl acetate (350 mL)
7. washThe combined organics were washed with 500 mL of brine
8. dry with materialdried over Na2SO4
9. filtrationfiltered
10. concentrationconcentrated

ORD-Eintrag

ord-187a45749f3f489386620217e3a1d130

Quelldatensatz

uspto-grants-2013_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08552205B2