C([O:8][C:9]1[CH:14]=[CH:13][C:12]([N:15]2[C:19]3=[N:20][CH:21]=[CH:22][C:23]([CH3:24])=[C:18]3[N:17]([CH3:25])[C:16]2=[O:26])=[CH:11][CH:10]=1)C1C=CC=CC=1.CCOC(C)=O>CN(C=O)C.[Pd]>[OH:8][C:9]1[CH:10]=[CH:11][C:12]([N:15]2[C:19]3=[N:20][CH:21]=[CH:22][C:23]([CH3:24])=[C:18]3[N:17]([CH3:25])[C:16]2=[O:26])=[CH:13][CH:14]=1A mixture of 3-[4-(benzyloxy)phenyl]-1,7-dimethyl-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one (2.0 g) and 10% Pd—C (0.308 g) in DMF (10 mL)—EtOAc (100 mL) was hydrogenated under balloon pressure at 20° C. for 1 h. The catalyst was removed by filtration and the filtrate was concentrated in vacuo. The residue was purified by column chromatography (NH silica gel, eluted with 50%-100% EtOAc in hexane) to give 3-(4-hydroxyphenyl)-1,7-dimethyl-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one (1.30 g) as a light brown solid. This product was subjected to the next reaction without further purification.
Loading…
