Formaldehyde → (2S,3S,4S,5R,6S)-3,4,5-tribenzyloxy-6-[4-chloro-3-[(2,3-difluoro-4-methoxy-phenyl)methyl]phenyl]-2-(hydroxymethyl)-6-methoxy-tetrahydropyran-2-carbaldehyde

Participants

Reaction Conditions

Reaction Steps

(2S,3S,4S,5R,6S)-3,4,5-tribenzyloxy-6-[4-chloro-3-[(2,3-difluoro-4-methoxy-phenyl)methyl]phenyl]-6-methoxy-tetrahydropyran-2-carbaldehyde 2k (1.24 g, 1.71 mmol) was dissolved in 15 mL 1,4-dioxane, followed by 37%-40% aqueous solution of formaldehyde (2.8 mL, 34.2 mmol) and 1.5 mL of sodium hydroxide solution (205 mg, 5.13 mmol). The reaction mixture was stirred overnight at 70° C. Thereafter, the reaction mixture was concentrated under reduced pressure and partitioned after 30 mL ethyl acetate and 15 mL saturated sodium chloride solution were added. The aqueous phase was extracted with ethyl acetate (15 mL×2) and the organic extract was combined, dried over anhydrous magnesium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain the title compound (2S,3S,4S,5R,6S)-3,4,5-tribenzyloxy-6-[4-chloro-3-[(2,3-difluoro-4-methoxy-phenyl)methyl]phenyl]-2-(hydroxymethyl)-6-methoxy-tetrahydropyran-2-carbaldehyde 2m (1.29 g, yellow grease), which was used directly in the next step without purification.

Provenance & Evidence