反应详情

To a suspension of 1-ethyl-6,7-bis((4-methoxybenzyl)oxy)-4-oxo-1,4-dihydrocinnoline-3-carboxylic acid (2.25 g, 4.59 mmol) in tetrahydrofuran (THF) (60 mL) was added triethylamine (2.110 mL, 15.14 mmol) and ethyl chloroformate (1.322 mL. 13.76 mmol). The resulting yellow solution was stirred at room temperature for 2 h, and was then added to a solution of sodium borohydride (2.083 g, 55.0 mmol) in ethanol (60 mL). After being stirred for 2 h, the reaction was quenched by addition of water (5 mL). The organic solvent was removed in vacuo, the residue was then taken in water (50 mL) and extracted with dichloromethane (2×50 mL). The combined extracts were dried over sodium sulfate, filtered and concentrated in vacuo. The crude product was purified by automatic silica gel column chromatography (Combiflash RF), eluting with methanol/dichloromethane (0-10%) to afford 1-ethyl-3-(hydroxymethyl)-6,7-bis((4-methoxybenzyl)oxy)cinnolin-4(1H)-one (1.97 g, 3.64 mmol, 79% yield) as a white solid. LCMS: (M+H)+: 477.1

1. stirringAfter being stirred for 2 h
2. customthe reaction was quenched by addition of water (5 mL)
3. customThe organic solvent was removed in vacuo
4. extractionextracted with dichloromethane (2×50 mL)
5. dry with materialThe combined extracts were dried over sodium sulfate
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customThe crude product was purified by automatic silica gel column chromatography (Combiflash RF)
9. washeluting with methanol/dichloromethane (0-10%)