Hydrochloric Acid → 4-Bromo-2,6-dinitroaniline

Temperatur

65 °C

A mixture of sodium sulfide nonahydrate (96 g, 400 mmol) and sulfur (12.8 g, 400 mmol) in a mixture of 400 mL of water and 100 mL of ethanol was heated at reflux under nitrogen for 1 h. The solution was added to a stirred suspension of 2-bromo-4,6-dinitrobenzenamine (104.8 g, 400 mmol) and ammonium chloride (20.8 g, 400 mmol) in a mixture of 400 mL of water and 700 mL of ethanol. The mixture was stirred at 65° C. for 30 min. Then 400 mL of 2N NaOH solution was added dropwise during a period of 30 min and the mixture was then stirred for a further 15 minutes at 65° C. After cooling, the mixture was poured onto a mixture of 2N HCl (400 mL), 1 kg ice and 1 L of water, stirred for 15 min to complete the reaction and extracted with ethyl acetate (1 L×3). The combined organic layers were dried over sodium sulphate and evaporated to give the crude product (90 g, 97%) as a rust-colored solid, which was used for the next step without further purification; LC/MS: MS (ES+) m/e 232 [M+H]+; 1H NMR (300 MHz, DMSO-d6) δ ppm 5.48 (s, 2H), 6.07 (s, 2H), 7.39 (d, J=2.7 Hz, 1H), 7.64 (d, J=2.7 Hz, 1H).

1. temperaturewas heated
2. temperatureat reflux under nitrogen for 1 h
3. stirringthe mixture was then stirred for a further 15 minutes at 65° C
4. temperatureAfter cooling
5. stirringstirred for 15 min
6. customthe reaction
7. extractionextracted with ethyl acetate (1 L×3)
8. dry with materialThe combined organic layers were dried over sodium sulphate
9. customevaporated

ORD-Eintrag

ord-ec40050bfb7c43a58c9a5ef6177975fa

Quelldatensatz

uspto-grants-2014_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08778937B2