Dimethylformamide → 2-chloro-1-(2-ethoxyethyl)-1H-benzimidazole

Participants

Reaction Conditions

Reaction Steps

Combine 2-chloro-1H-benzimidazole (21.1.4 g, 138.4 mmol) and dimethylformamide (200 mL). Add portionwise, sodium hydride (24.0 g, 60% in oil, 153.3 mmol). After 15 minutes, add 2-chloroethyl ethyl ether (21.9 g, 201,5 mmol). Heat to 60° C. After 18 hours, cool the reaction mixture and dilute with ethyl acetate. Extract with a saturated aqueous sodium bicarbonate solution, water, and then brine. Dry the organic layer over MgSO4, filter, and evaporate in vacuo to give a residue. Chromatograph the residue on silica gel eluting sequentially with 10% ethyl acetate/hexane and then 30% ethyl acetate hexane to give the 2-chloro-1-(2-ethoxyethyl)-1H-benzimidazole: Rf=0.74 (silica gel, 7/3 ethyl acetate/hexane).

Provenance & Evidence