Boron trifluoride → (2S,3R,4R,5S,6R)-2-[3-(4-benzyl-3,4-dihydro-2H-benzo[1,4]oxazin-6-ylmethyl)-4-chloro-phenyl]-6-hydroxymethyl-tetrahydro-pyran-3,4,5-triol

Participants

Reaction Steps

To a stirred solution of (2S,3R,4S,5S,6R)-2-[3-(4-benzyl-3,4-dihydro-2H-benzo[1,4]oxazin-6-ylmethyl)-4-chloro-phenyl]-6-hydroxymethyl-2-methoxy-tetrahydro-pyran-3,4,5-triol (5.0 g, 9.24 mmol) in acetonitrile-dichloromethane mixture 1:1 (40 mL) was added boron trifluoride diethyletharate complex (2.34 mL, 18.48 mmol), and triethylsilane (5.95 mL, 36.9 mmol) at −5° C. After stirring for 4 h at the same temperature, the reaction was quenched with aq. saturated sodium bicarbonate solution (15 mL). The volatiles were evaporated under reduced pressure, and the resulting mixture was extracted with dichloromethane (2×30 mL). The organic layers were combined and washed with brine (10 mL), dried over sodium sulfate, concentrated and purified by preparative HPLC to furnish (2S,3R,4R,5S,6R)-2-[3-(4-benzyl-3,4-dihydro-2H-benzo[1,4]oxazin-6-ylmethyl)-4-chloro-phenyl]-6-hydroxymethyl-tetrahydro-pyran-3,4,5-triol (3.5 g).

Provenance & Evidence