反应详情

A mixture of 3-[4-(benzyloxy)phenyl]-1-ethyl-7-methyl-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one (800 mg) and 10% Pd—C (118 mg) in EtOH (20 mL) was hydrogenated under balloon pressure at room temperature overnight. The catalyst was removed by filtration and the filtrate was concentrated in vacuo to give 1-ethyl-3-(4-hydroxyphenyl)-7-methyl-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one as a colorless solid. To a mixture of this solid and 3-methyl-2-(methylsulfonyl)-3H-imidazo[4,5-b]pyridine (480 mg) in DMF (10 ml) was added 60% sodium hydride (58.9 mg) at 100° C. The mixture was heated at 180° C. for 30 min under microwave irradiation. The reaction mixture was diluted with MeOH and concentrated under reduced pressure. The residue was purified by column chromatography (NH silica gel, eluted with 30%-50% AcOEt in hexane and silica gel, eluted with 15%-30% AcOEt in hexane). The crude materials were purified by HPLC (C18, eluted with H2O/MeCN containing 0.1% trifluoroacetic acid). To this obtained solution was added sat. NaHCO3 aq, the mixture was extracted with AcOEt, and the extract was dried over MgSO4 and concentrated in vacuo to give 1-ethyl-7-methyl-3-{4-[(3-methyl-3H-imidazo[4,5-b]pyridin-2-yl)oxy]phenyl}-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one (119 mg) as colorless crystals (Form A).

1. customThe catalyst was removed by filtration
2. concentrationthe filtrate was concentrated in vacuo