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

Participants

Reaction Conditions

Reaction Steps

(2S,3S,4S,5R,6S)-3,4,5-tribenzyloxy-6-[4-chloro-3-[[4-(trifluoromethoxy)phenyl]methyl]phenyl]-6-methoxy-tetrahydropyran-2-carbaldehyde 6n (1.21 g, 1.63 mmol) was dissolved in 12 mL 1,4-dioxane, followed by addition of 2.65 mL 37% formaldehyde solution and dropwise addition of 4.89 mL 1 M sodium hydroxide. The reaction mixture was stirred for 16 hours at 70° C. Thereafter, the reaction mixture was concentrated under reduced pressure and was partitioned after 30 mL of saturated sodium chloride solution were added. The aqueous phase was extracted with ethyl acetate (30 mL×3) 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-[[4-(trifluoromethoxy)phenyl]methyl]phenyl]-2-(hydroxymethyl)-6-methoxy-tetrahydro-pyran-2-carbaldehyde 6p (1.27 g, pale yellow grease), which was used directly in the next step without purification.

Provenance & Evidence