Ammonia → 3-Amino-5,6-dichloro-2-nitrotoluene

Temperatur

150 °C

A mixture of t-butyl (2-nitro-3,5,6-trichlorophenyl)acetate (123 g, 0.361 mol) and saturated aqueous ammonia (300 mL) in 2-methoxy ethanol (360 mL) was heated in an autoclave at 150° C. for 72 hours. The resulting viscous, black mixture was diluted with water (1 L) and ethyl acetate (1 L) and filtered through Arbocel filter aid. The dark red filtrate was separated, and the aqueous layer extracted with ethyl acetate (2×1 L). The combined organic solutions were washed with brine (1 L), dried (MgSO4) and evaporated onto silica gel (70-200μ, 200 g). The silica gel was applied to the top of a chromatography column containing silica gel (40-60 μ, 800 g). Elution with hexane/ethyl acetate (98:2-92:8) gave 3-amino-5,6-dichloro-2-nitrotoluene (EP-A-0385850) as a bright orange solid (39.7 g), which was contaminated with 5-amino-3,6-dichloro-2-nitrotoluene (14%). This mixture was carried onto the next step without further purification. 1H NMR (300 MD, CDCl3) 2.48 (3H, s), 4.80 (2H, s), 6.82 (1H, s).

1. filtrationfiltered through Arbocel
2. filtrationfilter aid
3. customThe dark red filtrate was separated
4. extractionthe aqueous layer extracted with ethyl acetate (2×1 L)
5. washThe combined organic solutions were washed with brine (1 L)
6. dry with materialdried (MgSO4)
7. customevaporated onto silica gel (70-200μ, 200 g)
8. additioncontaining silica gel (40-60 μ, 800 g)
9. washElution with hexane/ethyl acetate (98:2-92:8)

ORD-Eintrag

ord-512bbff28b704530b97d724f89fb9b6f

Quelldatensatz

uspto-grants-1998_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05783572