Triphenylphosphine → Ethyl 2-(2-(((2-(benzyloxy)-4,6-dimethylpyridin-3-yl)methyl)(tert-butoxycarbonyl)amino)ethoxy)-3-bromo-6-methyl-5-((methylsulfonyl)oxy)benzoate

Participants

Reaction Steps

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.

Provenance & Evidence