Hydrochloric Acid → 3-[4-(benzyloxy)phenyl]-7-methyl-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one

Participants

Reaction Steps

To a solution of N2-[4-(benzyloxy)phenyl]-4-methylpyridine-2,3-diamine (91.0 g) in THF (850 mL) was added N,N′-carbonylimidazol (90.8 g) at room temperature. The mixture was stirred at room temperature for 17 h. To the mixture was added 1 N NaOH (300 mL) over 10 min in ice bath, and the mixture was stirred for 15 min. To the mixture was added 1 N HCl (460 mL) under ice cooling, and then the mixture was stirred for 15 min. To the mixture was added water (90 mL) at room temperature, and then the mixture was stirred for 20 min. The precipitate was collected by filtration, washed with water (1.3 L), and dried in air blowing for 30 min. The precipitate was washed with IPE (1.5 L) and dried in vacuo at 55° C. for 2.5 h. The precipitate was suspended in IPE (500 mL), and the mixture was stirred at room temperature for 1 h. The precipitate was collected by filtration, washed with IPE (500 mL), and dried in vacuo to give 3-[4-(benzyloxy)phenyl]-7-methyl-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one (86 g) as a purple solid.

Provenance & Evidence