Ammonium Chloride → (1S,2R,3S,4R,5S)-3,4-dibenzyloxy-5-[4-chloro-3-[(4-ethoxyphenyl)methyl]phenyl]-2-hydroxy-6,8-dioxabicyclo[3.2.1]octane-1-carbaldehyde

Participants

Reaction Conditions

Reaction Steps

To a solution of (1S,2R,3S,4R,5S)-3,4-dibenzyloxy-5-[4-chloro-3-[(4-ethoxyphenyl)methyl]phenyl]-1-(hydroxymethyl)-6,8-dioxabicyclo[3.2.1]octan-2-ol 28j (0.22 g, 0.36 mmol) in dichloromethane (20 mL) was added saturated aqueous sodium bicarbonate (0.3 g, 3.6 mmol) at room temperature. To the mixture was added potassium bromide (25.7 mg, 0.22 mmol), 2,2,6,6-tetramethylpiperidinooxy (5.6 mg, 0.04 mmol) and sodium hypochlorite (0.8 mL, 0.94 mmol, 3.14% available chlorine) in turn at 0° C. The resulting mixture was stirred at 0° C. for 10 min and adjusted with saturated aqueous ammonium chloride till pH becomes 7. The resulting mixture was extracted with dichloromethane (15 mL×2). The combined organic layers were washed with water (10 mL×2) and saturated aqueous sodium chloride (10 mL×2), dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated in vacuo to give the title compound 28k as a white solid (221 mg, 100%).

Provenance & Evidence