(2R)-3-[tert-butyl(diphenyl)silyl]oxy-2-methylpropan-1-ol

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Under argon atmosphere, (R)-3-(t-butyldiphenylsilyloxy)-2-methylpropanol (48) (725 mg, 2.2 mmol) was dissolved in 40 ml of dry dichloromethane. MS-4A (30 mg), NMO (862 mg, 11.1 mmol) and TPAP (catalytic amount) were added to the resultant solution at 0° C., and the mixture was stirred for 15 min. The reaction mixture was further stirred overnight after the temperature was returned to room temperature. Subsequently, H2O was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with brine, dried over magnesium sulfate and evaporated. The obtained crude product was purified by column chromatography (21 g, 4% AcOEt-hexane) to obtain a colorless oily product (49) (700 mg, 97%). The reaction mixture was further stirred overnight was returned to room temperature the mixture was extracted with ethyl acetate The ethyl acetate layer was washed with brine dried over magnesium sulfate evaporated The obtained crude product was purified by column chromatography (21 g, 4% AcOEt-hexane)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Under argon atmosphere, Methyl(S)-3-(t-butyldiphenylsilyloxy)-2-metylpropionate (47) (1.0 g, 2.7 mmol) was dissolved in 50 ml of dry toluene, 1M DIBAL-H/hexane (5.7 ml, 5.7 mmol) was added to the resultant solution at 0° C., and the mixture was stirred for 15 min. Subsequently, the reaction mixture was further stirred for 45 min after the temperature was returned to room temperature. Ethyl acetate was added to the reaction mixture to decompose the excess DIBAL-H, and the resultant mixture was extracted with 0.5N HCl. The ethyl acetate layer was washed with brine, dried over magnesium sulfate and evaporated. The obtained crude product was purified by column chromatography (30 g, 4-10% AcOEt-hexane) to obtain a colorless oily product (48) (968 mg, quant.). Subsequently, the reaction mixture was further stirred for 45 min after the temperature was returned to room temperature the resultant mixture was extracted with 0.5N HCl The ethyl acetate layer was washed with brine dried over magnesium sulfate evaporated The obtained crude product was purified by column chromatography (30 g, 4-10% AcOEt-hexane)