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

Participants

Reaction Conditions

Reaction Steps

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) δ1.40 (t, 3H), 4.41 (m, 2H), 7.84 (1H, C2H) and 11.55 (br s, 1H, NH).

Provenance & Evidence