Diethyl Carbonate → 3-ethyl-2-naphthalen-1-yl-3H-imidazole-4-carboxylic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

To a solution of 1-ethyl-2-naphthalen-1-yl-1H-imidazole (1.11 g, 5 mmol) in anhydrous THF (30 ml) at −78° C. under nitrogen is added a solution of n-BuLi in hexane (1.6 M, 3.44 ml, 5.5 mmol, 1.1 eq.) dropwise. The resulting mixture is stirred at −78° C. for 1 hr, followed by the addition of diethyl carbonate (1.77 g, 15 mmol, 3.0 eq.). The resulting solution is stirred at −78° C. for 30 min, warmed to rt slowly, and stirred for an additional 30 min at rt. Water (30 ml) is added to quench the reaction, and THF is evaporated under reduced pressure. The residue is extracted with EtOAc (30 ml×2) and the combined organic layers are washed with water and brine, dried over sodium sulfate, and concentrated. The crude product is purified through silica gel chromatography (hexanes/EtOAc, from 8:1 to 4:1) to give 3-ethyl-2-naphthalen-1-yl-3H-imidazole-4-carboxylic acid ethyl ester. LCMS 295 (M+1).

Provenance & Evidence