Hydrochloric Acid → 6-Cyclopropyl-8-[(2,6-difluorobenzyl)oxy]-2-methylimidazo[1,2-a]pyridine-3-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

470 mg of ethyl 6-cyclopropyl-8-[(2,6-difluorobenzyl)oxy]-2-methylimidazo[1,2-a]pyridine-3-carboxylate (Example 41A) were initially charged in 36 ml of tetrahydrofuran/methanol 5:1, and 6.1 ml of 1N aqueous lithium hydroxide solution were added. The mixture was stirred at 40° C. for 4 h and then acidified with 6 N hydrochloric acid and concentrated. The residue was taken up in water and repeatedly extracted with dichloromethane. The combined organic phases were washed with saturated aqueous sodium chloride solution, dried with magnesium sulphate and filtered, and the filtrate was concentrated. This gave 470 mg of the desired product (90% pure; 97% of theory) which was reacted without further purification.

Provenance & Evidence