Boron trifluoride → (2S,3R,4R,5S,6R)-2-[3-[(4-benzylspiro[3H-1,4-benzoxazine-2,1'-cyclopropane]-6-yl)methyl]-4-chloro-phenyl]-6-(hydroxymethyl)tetrahydropyran-3,4,5-triol

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of (3R,4S,5S,6R)-2-[3-[(4-benzylspiro[3H-1,4-benzoxazine-2,1′-cyclopropane]-6-yl)methyl]-4-chloro-phenyl]-6-(hydroxymethyl)-2-methoxy-tetrahydropyran-3,4,5-triol (340 mg, 0.6 mmol) in acetonitrile-dichloromethane (6 mL, 1:1 mixture) was added triethylsilane (0.4 mL, 2.4 mmol) and boron trifluoride diethyletharate complex (0.15 mL, 1.2 mmol) at −5° C. After stirring for 4 h at 0° C., the reaction was quenched with saturated aq. sodium bicarbonate solution (5 mL). The volatiles were evaporated under reduced pressure, and the resulting mixture was extracted with ethyl acetate (3×10 mL). The ethyl acetate layers were combined and washed with brine (10 mL), dried over sodium sulphate, and concentrated. The resulting residue was purified by silica gel column chromatography to furnish (2S,3R,4R,5S,6R)-2-[3-[(4-benzylspiro[3H-1,4-benzoxazine-2,1′-cyclopropane]-6-yl)methyl]-4-chloro-phenyl]-6-(hydroxymethyl)tetrahydropyran-3,4,5-triol (300 mg).

Provenance & Evidence