反应详情

3aS,4R,6aR)-5-iodo-2,2-dimethyl-4,6a-dihydro-3aH-cyclopenta[d][1,3]dioxol-4-ol (5-3) (1.5 g, 5.3 mmol, 1 equiv) was dissolved in DMF (6 mL) and imidazole (1.3 g, 18/4 mmol, 3.5 equiv) was added followed by TBDPS-Cl (3.0 mL, 11.6 mmol, 2.2 equiv). The resulting mixture was stirred at ambient temperature for 30 minutes. Upon disappearance of starting material, the mixture was diluted with 50 mL EtOAc and washed with water (2×50 mL). The organic layer was dried over MgSO4, filtered and concentrated. The crude residue was purified by flash chromatography (120 g SiO2, 0-20% EtOAc in hexanes) to yield tert-butyl((3aR,4R,6aR)-5-iodo-2,2-dimethyl-4,6a-dihydro-3aH-cyclopenta[d][1,3]dioxol-4-yloxy)diphenylsilane (5-4) as a colorless oil. 1H NMR (500 MHz, CDCl3): δ 7.82 (t, J=8 Hz, 4H); 7.34-7.44 (m, 6H); 6.33 (s, 1H); 4.61 (dd, J=5.5, 2.0 Hz, 1H); 4.46 (dd, J=5.5, 2.0 Hz, 1H); 3.91 (t, J=5.5 Hz, 1H); 1.40 (s, 3H); 1.21 (s, 3 II); 1.16 (s, 9H).

1. washwashed with water (2×50 mL)
2. dry with materialThe organic layer was dried over MgSO4
3. filtrationfiltered
4. concentrationconcentrated
5. customThe crude residue was purified by flash chromatography (120 g SiO2, 0-20% EtOAc in hexanes)