Dimethyl Sulfate → 1,4-Dimethyl-5-nitro-1H-imidazole

HRID 2397217Notes

Reaction equation

HRID 2397217 reaction equation
[CH3:1][C:2]1[N:3]=[CH:4][NH:5][C:6]=1[N+:7]([O-:9])=[O:8].S(OC)(O[CH3:14])(=O)=O>C(O)=O>[CH3:1][C:2]1[N:3]=[CH:4][NH:5][C:6]=1[N+:7]([O-:9])=[O:8].[CH3:14][N:5]1[C:6]([N+:7]([O-:9])=[O:8])=[C:2]([CH3:1])[N:3]=[CH:4]1

Participants

5

Reactant 2

HCID 6497Dimethyl SulfateHCID 862781031H-Imidazole, 4-methyl-5-nitro-

Product 2

HCID 1488121,4-Dimethyl-5-nitro-1H-imidazoleHCID 862781031H-Imidazole, 4-methyl-5-nitro-

Reagents, catalysts & solvents 1

HCID 284Formic AcidSolvent

Conditions

Temperature
5 °C

Procedure

127 parts of 4-methyl-5-nitroimidazole is heated under reflux with 350 parts of formic acid and 126 parts of dimethyl sulfate for 4 hours. The formic acid is distilled off in vacuo and the residue is dissolved in 500 parts of water and adjusted to pH 1.8 with aqueous ammonia solution. The mixture is cooled to 5° C. and the unreacted 4-methyl-5-nitroimidazole is suction filtered. The filtrate is adjusted to pH 10 with aqueous ammonia solution and is continuously exhaustively extracted with ethyl acetate. The extract is evaporated in vacuo. The oily residue crystallizes on standing. 47 parts of unreacted 4-methyl-5-nitroimidazole and 66 parts of 1,4-dimethyl-5-nitroimidazole melting at 45° C. are obtained; this is equivalent to a yield of 74% of theory.

Workup

  1. distillationThe formic acid is distilled off in vacuo
  2. dissolutionthe residue is dissolved in 500 parts of water
  3. filtrationfiltered
  4. extractionis continuously exhaustively extracted with ethyl acetate
  5. customThe extract is evaporated in vacuo
  6. customThe oily residue crystallizes

Sources & evidence

ORD record
ord-10394a216f7147a3aaba36002ba672b0
Source dataset
uspto-grants-1977_05
Patent number
US04021442

Reaction notes

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