反应详情

To a solution of (R)-benzyl 3-(4-(benzyloxy)phenyl)-2-hydroxypropanoate (Compound XLIII-1) 18.1 g (50.0 mmol) in dichloromethane 80 ml, trifluoromethanesulfonic anhydride 10.1 ml (60.0 mmol) and 2,6-lutidine 8.74 ml (75.0 mmol) were added and the mixture was stirred at room temperature for 0.5 hr. N-hydroxyphthalimide 8.16 g (50.0 mmol) and triethylamine 10.5 ml (75.0 mmol) were added to the reaction mixture and the mixture was stirred at room temperature overnight. The reaction mixture was concentrated in vacuo and diluted with ethyl acetate 500 ml and washed with saturated sodium bicarbonate solution 500 ml, water 500 ml and brine 500 ml. The organic phase was dried over magnesium sulfate and filtered. The filtrate was concentrated in vacuo and the residue was purified on silica gel column chromatography (Merck 60N spherical, neutral elution by n-hexane:ethyl acetate=90:10 to 70:30) to obtain the title compound 15.0 g (yield 59%).

1. stirringthe mixture was stirred at room temperature overnight
2. concentrationThe reaction mixture was concentrated in vacuo
3. additiondiluted with ethyl acetate 500 ml
4. washwashed with saturated sodium bicarbonate solution 500 ml, water 500 ml and brine 500 ml
5. dry with materialThe organic phase was dried over magnesium sulfate
6. filtrationfiltered
7. concentrationThe filtrate was concentrated in vacuo
8. customthe residue was purified on silica gel column chromatography (Merck 60N spherical, neutral elution by n-hexane:ethyl acetate=90:10 to 70:30)