反应详情

A solution of ethyl 3-bromo-2-hydroxy-6-methyl-5-((methylsulfonyl)oxy)benzoate (116d, 593 mg, 1.5 mmol), triphenylphosphine (0.50 g, 1.9 mmol), and tert-butyl ((2-(benzyloxy)-4,6-dimethylpyridin-3-yl)methyl)(2-hydroxyethyl)carbamate (Cpd LL, 0.54 g, 1.5 mmol) in tetrahydrofuran (12 mL) was cooled to 0° C. then diisopropyl azodicarboxylate (0.40 mL, 1.9 mmol) was added drop wise. The reaction was slowly warmed to room temperature and stirred overnight. The reaction was diluted with water (15 mL) and extracted with ethyl acetate (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)(tert-butoxycarbonyl)amino)ethoxy)-3-bromo-6-methyl-5-((methylsulfonyl)oxy)benzoate (116e, 0.58 g, 52% yield) as a white solid.

1. extractionextracted with ethyl acetate (2×15 mL)
2. washThe combined organic layers were washed with brine (15 mL)
3. dry with materialdried over magnesium sulfate
4. concentrationconcentrated under vacuum
5. custompurified by column chromatography (20% EtOAc/Heptane)