Dimethylformamide dimethyl acetal → 9-Cyclohexyl-3-{[2-(trimethylsilyl)ethoxy]methyl}-3H-imidazo[4,5-h][1,6]naphthyridin-6(9H)-one
Reaction equation
[CH:1]1([NH:7][C:8]2[C:13]([C:14](=[O:16])[CH3:15])=[CH:12][N:11]=[C:10]3[N:17]([CH2:20][O:21][CH2:22][CH2:23][Si:24]([CH3:27])([CH3:26])[CH3:25])[CH:18]=[N:19][C:9]=23)[CH2:6][CH2:5][CH2:4][CH2:3][CH2:2]1.[CH3:28]OC(OC)N(C)C>>[CH:1]1([N:7]2[C:8]3[C:9]4[N:19]=[CH:18][N:17]([CH2:20][O:21][CH2:22][CH2:23][Si:24]([CH3:26])([CH3:25])[CH3:27])[C:10]=4[N:11]=[CH:12][C:13]=3[C:14](=[O:16])[CH:15]=[CH:28]2)[CH2:6][CH2:5][CH2:4][CH2:3][CH2:2]1Participants
3
Procedure
1-[7-(Cyclohexylamino)-3-{[2-(trimethylsilyl)ethoxy]methyl}-3H-imidazo[4,5-b]pyridin-6-yl]ethanone (88.9 mg, 0.229 mmol) in N,N-dimethylformamide dimethyl acetal (2.0 mL) was stirred at 180° C. for 5 hours. The reaction mixture was allowed to cool to room temperature and concentrated under reduced pressure, and the resulting residue was dissolved in tetrahydrofuran (5 mL) and stirred with 1 M hydrochloric acid (2 mL) at 80° C. for 1 hour. The reaction mixture was allowed to cool to room temperature and, after addition of saturated aqueous sodium hydrogen carbonate, extracted with ethyl acetate, and the organic layer was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/ethyl acetate/methanol=1/1/0→0/10/1 (v/v/v)) to give the title compound as a yellow solid (57.5 mg, yield 63%).