反应详情

To a solution of (2S,3R,4R,5S)-3,4,5-tris(benzyloxy)-2-(benzyloxymethyl)-6-(3-(bromomethyl)-4-chlorophenyl)-tetrahydro-2H-pyran (195 mmol) from Step 7 in ethanol (260 mL) and water (130 mL) was added potassium cyanide (31.8 g, 488 mmol). The reaction mixture was refluxed overnight. After cooling to room temperature, the mixture was diluted with water and extracted with ethyl acetate. The organic layer was washed with brine, dried over magnesium sulfate, filtered and evaporated in vacuo. Flash chromatography on a Biotage® apparatus (silica gel, 5 to 40% ethyl acetate in hexanes gradient) gave the title compound (105 g, 156 mmol, 80%, mixture of α,β-anomer in about 1:2 ratio) as a colorless oil.

1. temperatureThe reaction mixture was refluxed overnight
2. extractionextracted with ethyl acetate
3. washThe organic layer was washed with brine
4. dry with materialdried over magnesium sulfate
5. filtrationfiltered
6. customevaporated in vacuo