Sodium borohydride → [(3S,4S,5R,6S)-3,4,5-tribenzyloxy-6-[4-chloro-3-[[4-(trifluoromethoxy)phenyl]methyl]phenyl]-2-(hydroxymethyl)-6-methoxy-tetrahydropyran-2-yl]methanol

Participants

Reaction Steps

(2S,3S,4S,5R,6S)-3,4,5-tribenzyloxy-6-[4-chloro-3-[[4-(trifluoromethoxy)phenyl]methyl]phenyl]-2-(hydroxymethyl)-6-methoxy-tetrahydropyran-2-carbaldehyde 6p (1.27 g, 1.63 mmol) was dissolved in 10 mL of mixed solution (THF and MeOH, v:v=1:1) and followed by addition of sodium borohydride (0.12 g, 3.26 mmol) in batch. The reaction mixture was stirred for 1.5 hours. Thereafter, the reaction mixture was concentrated under reduced pressure and was partitioned after 30 mL of ethyl acetate were added. The organic extract was washed with saturated sodium chloride solution (15 mL×2), combined, dried over anhydrous magnesium sulfate, and filtered. The filtrate was concentrated under reduced pressure and the resulting residue was purified by silica gel chromatography with elution system E to obtain the title compound [(3S,4S,5R,6S)-3,4,5-tribenzyloxy-6-[4-chloro-3-[[4-(trifluoromethoxy)phenyl]methyl]phenyl]-2-(hydroxymethyl)-6-methoxy-tetrahydropyran-2-yl]methanol 6q (400 mg, white solid), yield: 31.5%. 1H NMR (400 MHz, CD3OD): δ 7.58 (dd, 1H), 7.54 (d, 1H), 7.39 (d, 1H), 7.31-7.24 (m, 13H), 7.16 (d, 2H), 7.11-7.06 (m, 4H), 4.92 (d, 1H), 4.76 (d, 1H), 4.66-4.59 (m, 1H), 4.27-4.22 (m, 2H), 4.17-4.10 (m, 2H), 4.07-4.04 (m, 3H), 3.99-3.95 (m, 2H), 3.77 (d, 1H), 3.65-3.60 (m, 2H), 3.35 (s, 2H), 3.18 (s, 3H).

Provenance & Evidence