反应详情

A solution of (S)-N-((2S,3S)-3,4-bis(tert-butyldimethylsilyloxy)-1-(tetrahydrofuran-3-yl)butan-2-yl)-2-methylpropane-2-sulfinamide (1.5 g, 3.0 mmol) in dry MeOH (30 mL) was brought to −20° C. followed by the addition of 10% HCl (100 mL, MeOH/acetyl chloride) and the resulting mixture was stirred at −20 C for 1 h. The mixture was quenched with 10% Na2CO3 and extracted with DCM (8×). The combined organics were dried over Na2CO4, filtered, concentrated and colorless oil obtained was dissolved in DCM (30 mL) followed by the addition of TEA (1.2 mL, 8.9 mmol) and di-tert-butyldicarbonate (1.0 mL, 4.4 mmol). The reaction was stirred at RT for 17 h. The mixture was concentrated and chromatographed on silica gel using 4:1 to 1:1 EtOAc/hexanes to afford a colorless oil as tert-butyl(2S,3S)-3(tert-butyldimethylsilyloxy)-4-hydroxy-1-((S)-tetrahydrofuran-3-yl)butan-2-ylcarbamate AND Tert-butyl(2S,3S)-3 (tert-butyldimethylsilyloxy)-4-hydroxy-1-((R)-tetrahydrofuran-3-yl)butan-2-ylcarbamate.

1. customwas brought to −20° C.
2. customThe mixture was quenched with 10% Na2CO3
3. extractionextracted with DCM (8×)
4. dry with materialThe combined organics were dried over Na2CO4
5. filtrationfiltered
6. concentrationconcentrated
7. customcolorless oil obtained
8. stirringThe reaction was stirred at RT for 17 h
9. concentrationThe mixture was concentrated
10. customchromatographed on silica gel using 4:1 to 1:1 EtOAc/hexanes