4-Phenyl-1-butyne → ethyl 2-methyl-4-(4-phenylbut-1-ynyl)-1H-imidazole-1-carboxylate

Participants

Reaction Steps

In a dry reaction tube containing in suspension iodide copper (20 mg, 0.1 mmol) and triethylamine (5.81 mL 41.40 mmol), were added ethyl 4-iodo-2-methyl-1H-imidazole-1-carboxylate (580 mg, 2.07 mmol) and the Pd(PPh3)2Cl2 (66 mg, 0.1 mmol). A yellow suspension is obtained and after a few minutes stirred at room temperature was added the commercially available 4-phenyl-1-butyn (269 mg, 2.07 mmol) in triethylamine (0.5 mL). Immediately the color of the reaction turns to black. The mixture was stirred at room temperature for 30 min and then at 80° C. for 20 h Triethylamine was concentrated under reduce pressure and the residue was dissolved in DCM. The organic layer was washed with saturated NH4Cl, water and brine, dried (MgSO4) and concentrated. Purification by flash chromatography (prepacked 25 g silicagel column, DCM/MeOH: 99/1 as eluent to afford 410 mg of ethyl 2-methyl-4-(4-phenylbut-1-ynyl)-1H-imidazole-1-carboxylate (Yield: 70%) as a brown oil.

Provenance & Evidence