Sodium Hydroxide → 2-(3-Chlorophenyl)-3H-imidazo[4,5-b]pyridine-3-acetic acid

Participants

Reaction Steps

A mixture of 2-(3-chlorophenyl)-3H-imidazo[4,5-b]pyridine-3-acetic acid ethyl ester (6.0 g, 0.019 mole), sodium hydroxide pellets (0.9 g, 0.023 mole), and 50 ml of ethanol-water (2:1) was refluxed for 1 hour. The reaction mixture was cooled and the ethanol evaporated in vacuo. The residual aqueous mixture was diluted with water (40 ml) and extracted with diethyl ether (2×25 ml). The aqueous portion was acidified with concentrated hydrochloric acid to a pH of 5-6. After precipitation was complete, the solid was collected by filtration, giving 5.9 g (100%). Recrystallization from ethanol gave 4.7 g of cream colored needles, mp 214°-216° C.

Provenance & Evidence