Reaction #696714

Reaction equation

Ethyl 1-methylimidazole-2-carboxylate

nitric acid

→

Ethyl 1-methyl-4-nitroimidazole-2-carboxylate

Solvents

sulfuric acid

Conditions

Workup

1. 1
   Temperaturemaintaining a temperature of 0° C
2. 2
   TemperatureThe reaction was then refluxed with an efficient condenser (-20° C.) in a well ventilated hood for 50 min
3. 3
   TemperatureThe reaction was cooled with an ice bath
4. 4
   Otherquenched
5. 5
   workup.ADDITIONby pouring onto 10 L ice
6. 6
   ExtractionThe resulting blue solution was then extracted with 20 L DCM
7. 7
   Dryingthe combined extracts dried (sodium sulfate)
8. 8
   Concentrationconcentrated in vacuo
9. 9
   Otherto yield a tan solid which
10. 10
    Otherwas recrystallized from 22 L of 21:1 carbon tetrachloride/ethanol
11. 11
    FiltrationThe resulting white crystals are collected by vacuum filtration

Procedure

Ethyl 1-methylimidazole-2-carboxylate was carefully dissolved in 1000 mL of concentrated sulfuric acid cooled to 0° C. 90% nitric acid (1 L) was slowly added maintaining a temperature of 0° C. The reaction was then refluxed with an efficient condenser (-20° C.) in a well ventilated hood for 50 min. The reaction was cooled with an ice bath, and quenched by pouring onto 10 L ice. The resulting blue solution was then extracted with 20 L DCM, the combined extracts dried (sodium sulfate) and concentrated in vacuo to yield a tan solid which was recrystallized from 22 L of 21:1 carbon tetrachloride/ethanol. The resulting white crystals are collected by vacuum filtration.

Source