Ethanol → Diethyl 1H-imidazole-4,5-dicarboxylate

HRID 1267802Notes

Reaction equation

HRID 1267802 reaction equation
[NH:1]1[C:5]([C:6]([OH:8])=[O:7])=[C:4]([C:9]([OH:11])=[O:10])[N:3]=[CH:2]1.[CH2:12](N(CC)CC)[CH3:13].[CH2:19](O)[CH3:20]>ClCCl>[NH:1]1[C:5]([C:6]([O:8][CH2:12][CH3:13])=[O:7])=[C:4]([C:9]([O:11][CH2:19][CH3:20])=[O:10])[N:3]=[CH:2]1

Participants

5

Reactant 3

HCID 702EthanolHCID 8471TriethylamineHCID 684421H-Imidazole-4,5-dicarboxylic acid

Product 1

HCID 350670Diethyl 1H-imidazole-4,5-dicarboxylateYield 52%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Conditions

Temperature
0 °C

Procedure

Imidazole-4,5-dicarboxylic acid (7.55 g, 50.0 mmol) is dissolved in absolute ethyl alcohol (120 mL). The solution was cooled in an ice bath to 0° C. and bubbled dry HCl gas for 1 h. Later, the reaction mixture was refluxed at 80° C. for 7 h during which time all the starting material was consumed. The solvent was removed and the residue that obtained was dissolved in dichloromethane (200 mL) and the organic layer was neutralized with triethylamine. The organic layer was washed with cold water (100 mL) and brine (50 mL), dried over anhydrous sodium sulfate and concentrated in vacuo to give 5.50 g (52%) of white solid: mp 175-177° C.; 1H NMR (CDCl3) δ 1.40 (t, 3H), 4.41 (m, 2H), 7.84 (1H, C2H) and 11.55 (br s, 1H, NH).

Workup

  1. custombubbled dry HCl gas for 1 h
  2. temperatureLater, the reaction mixture was refluxed at 80° C. for 7 h during which time all the starting material
  3. customwas consumed
  4. customThe solvent was removed
  5. customthe residue that obtained
  6. washThe organic layer was washed with cold water (100 mL) and brine (50 mL)
  7. dry with materialdried over anhydrous sodium sulfate
  8. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-469a78890e0047bbafb8603b17b910ca
Source dataset
uspto-grants-2003_04
Patent number
US06552183B1

Reaction notes

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