Reaktion #3232

Reaktionsgleichung

sodium nitrite

2-chloro-4-methyl-6-nitroaniline

sulfuric acid

→

title compound

Ausbeute 92.0%

3-Chloro-5-nitrotoluene

Ausbeute 92.0%

Lösungsmittel

water

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONto exceed 5° C. during the addition
2. 2
   workup.ADDITIONAfter the addition
3. 3
   Temperaturat reflux until the evolution of gas from the reaction mixture
4. 4
   Temperaturto cool
5. 5
   Einengenwas concentrated
6. 6
   Filtrationfiltered
7. 7
   Sonstigeto remove the solids
8. 8
   EinengenThe filtrate was concentrated
9. 9
   Sonstigethe residue chromatographed (eluant: diethyl ether/hexane; 1/9)

Vorschrift

To a stirred mixture of 2-chloro-4-methyl-6-nitroaniline (7.39 g, 39.7 mM) and concentrated sulfuric acid (6.2 mL) in absolute ethanol (50 mL) at 0°-5° C. was slowly added a solution of sodium nitrite (6.85 g, 99.3 mM) in water (6 mL). The temperature of the reaction mixture was not allowed to exceed 5° C. during the addition. After the addition was completed, the reaction mixture was stirred at room temperature for 0.5 hr and then at reflux until the evolution of gas from the reaction mixture ceased. The reaction mixture was allowed to cool and was concentrated. The residue was slurried with ether and then filtered to remove the solids. The filtrate was concentrated and the residue chromatographed (eluant: diethyl ether/hexane; 1/9) to provide (6.25 g, 92%) the title compound as a yellow crystalline solid, mp 60.5-61° C.; MS(CI): 172 (M+H).

Quelle