反应详情

温度

-78 °C

(3aR,6S,6aR)-2,2,6-trimethyldihydro-3aH-cyclopenta[d][1,3]dioxol-4(5H)-one (6-1) (490 mg, 2.7 mmol, 1 equiv) was dissolved in dry DCM (55 mL) and 3A molecular sieves were added. The mixture was cooled to −78° C. and DIBAL (4.1 mL, 4.1 mmol, 1.5 equiv, 1.0M in heptane) was added dropwise. The resulting mixture stirred at the same temperature for 4 hours. Upon disappearance of the starting material, MeOH (6 mL) was added to quench the reaction. Water (10 mL) was added and the mixture was filtered through celite washing with DCM (2×30 mL). The organic layer was separated, dried over MgSO4, filtered and concentrated to afford (3aS,4S,6S,6aR)-2,2,6-trimethyltetrahydro-3aH-cyclopenta[d][1,3]dioxol-4-ol (6-2) as a colorless oil. 1H NMR (500 MHz, CDCl3): δ 4.50 (t, J=6.0 Hz, 1H); 4.27 (d, J=5.5 Hz, 1H); 4.12 (quin, J=6.0 Hz, 1H); 2.46 (d, J=8.5 Hz, 1H); 2.15 (quirt, J=4.5 Hz, 1H); 1.85 (m, 1H); 1.64 (dq, J=12.5, 3.0 Hz, 1H); 1.49 (s, 3H); 1.34 (s, 3H); 0.93 (d, J=8.0 Hz, 3H).

1. customto quench
2. customthe reaction
3. filtrationthe mixture was filtered
4. washthrough celite washing with DCM (2×30 mL)
5. customThe organic layer was separated
6. dry with materialdried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated