反应详情

tert-Butyldimethylsilylchloride (2.78 g, 18.5 mmol) in DMF (30 mL) was added dropwise over 3 h to the alcohol from Step 1 (5.43 g) and imidazole (1.33 g) in DMF (50 mL) at 0° C. After the addition was complete the ice bath was removed and the reaction warmed to room temperature overnight. The DMF solution was diluted with ether (400 mL) then washed with water (2×75 mL), sat'd NaHCO3 (1×75 mL), and brine (1×075 mL). The organic layer was dried over MgSO4, filtered, and then evaporated to dryness. The product was purified by flash chromatography (silica gel, 20-40% ethyl acetate/hexanes) to provide benzyl (1S,2R,4R)-2-((tert-butyldimethylsilyloxy)methyl)-4-hydroxycyclohexylcarbamate (4.15 g) as a color less oil. MS found: (M+H)+=394.

1. additionAfter the addition
2. customwas removed
3. additionThe DMF solution was diluted with ether (400 mL)
4. washthen washed with water (2×75 mL), sat'd NaHCO3 (1×75 mL), and brine (1×075 mL)
5. dry with materialThe organic layer was dried over MgSO4
6. filtrationfiltered
7. customevaporated to dryness
8. customThe product was purified by flash chromatography (silica gel, 20-40% ethyl acetate/hexanes)