2-(Bromomethoxy)ethyl acetate → acetic acid 2-(3H-imidazo[4,5-b]pyridin-3-ylmethoxy)-ethyl ester

Participants

Reaction Steps

To a solution of 1.0 g (8.39 mmol) 3H-imidazo[4,5-b]pyridine in 20 ml DMF kept under argon at 0° C. 0.94 g (8.39 mmol) potassium tert-butoxide were added. The solution was warmed to room temperature and after 1 hour a solution of 1.74 g (8.8 mmol) (2-acetoxyethoxy)methyl bromide in 5 ml DMF was added dropwise over half an hour. The reaction was stirred at room temperature for 20 hours and then poured onto 75 ml of ice water. The mixture was extracted twice with 50 ml ethyl acetate. The combined organic layers were washed with water and brine, dried over Na2SO4 filtered and concentrated in vacuo. The crude product was purified by flash chromatography (silica gel, gradient DCM, DCM/MeOH 95/5 and 9/1) to afford 0.81 g (41%) of the desired product. MS(ISP): 236.2 [MH]+.

Provenance & Evidence