Reaction #3232

Reaction equation

sodium nitrite

2-chloro-4-methyl-6-nitroaniline

sulfuric acid

→

title compound

Yield 92.0%

3-Chloro-5-nitrotoluene

Yield 92.0%

Solvents

water

ethanol

Conditions

Workup

1. 1
   workup.ADDITIONto exceed 5° C. during the addition
2. 2
   workup.ADDITIONAfter the addition
3. 3
   Temperatureat reflux until the evolution of gas from the reaction mixture
4. 4
   Temperatureto cool
5. 5
   Concentrationwas concentrated
6. 6
   Filtrationfiltered
7. 7
   Otherto remove the solids
8. 8
   ConcentrationThe filtrate was concentrated
9. 9
   Otherthe residue chromatographed (eluant: diethyl ether/hexane; 1/9)

Procedure

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).

Source