反应详情

To a solution of ethyl 2-(2-(((2-(benzyloxy)-4,6-dimethylpyridin-3-yl)methyl)(tert-butoxycarbonyl)amino)ethoxy)-3-bromo-6-methyl-5-((methylsulfonyl)oxy)benzoate (116e, 0.58 g, 0.80 mmol) in dichloromethane (8 mL) was added 85% phosphoric acid (0.20 mL, 2.8 mmol). The mixture was stirred at room temperature for 2 hours then additional 85% phosphoric acid (0.20 mL, 2.8 mmol) was added and stirring was continued for 2 hours. The reaction was carefully quenched with saturated aqueous sodium bicarbonate (10 mL) and extracted with dichloromethane (2×15 mL). The combined organic layers were washed with brine (15 mL), dried over magnesium sulfate, concentrated under vacuum, and purified by column chromatography (20% EtOAc/Heptane) to give ethyl 2-(2-(((2-(benzyloxy)-4,6-dimethylpyridin-3-yl)methyl)amino)ethoxy)-3-bromo-6-methyl-5-((methylsulfonyl)oxy)benzoate (116f, 0.25 g, 50% yield) as a clear sticky solid.

1. stirringstirring
2. waitwas continued for 2 hours
3. customThe reaction was carefully quenched with saturated aqueous sodium bicarbonate (10 mL)
4. extractionextracted with dichloromethane (2×15 mL)
5. washThe combined organic layers were washed with brine (15 mL)
6. dry with materialdried over magnesium sulfate
7. concentrationconcentrated under vacuum
8. custompurified by column chromatography (20% EtOAc/Heptane)