Pyridine → (3aR,4S,6aR)-2,2-dimethyl-4,6a-dihydro-3aH-cyclopenta[d][1,3]dioxol-4-yl methyl carbonate

Temperature

0 °C

(3aS,4S,6aR)-2,2-dimethyl-4,6a-dihydro-3aH-cyclopenta[d][1,3]dioxol-4-ol (2-1) (9.76 g, 62.5 mmol, 1.0 equiv) was dissolved in DCM (200 mL). Pyridine (7.58 mL, 94.0 mmol, 1.5 equiv) was added and the mixture stirred at 0° C. After 1 hour DMAP (3.05 g, 25.0 mmol, 0.4 equiv) was added followed by methyl chloroformate (19.4 mL, 250 mmol, 4 equiv). The resulting mixture was stirred overnight, and the temperature was allowed to slowly increase to room temperature. The reaction was partitioned between DCM and water, and the organic layer was separated and washed with water, dried (MgSO4), and concentrated to yield desired (3aR,4S,6aR)-2,2-dimethyl-4,6a-dihydro-3aH-cyclopenta[d][1,3]dioxol-4-yl methyl carbonate (2-2) as a colorless oil. 1H NMR (500 MHz, CDCl3): δ 6.10 (d, J=5.9 Hz, 1H); 5.91 (d, J=5.9 Hz, 1H); 5.30 (d, J=5.4 Hz, 1H); 5.03 (d, J=5.7 Hz, 1H); 4.92 (t, J=5.5 Hz, 1H); 3.83 (s, 3H); 1.40 (s, 3H); 1.38 (s, 3H).

1. stirringThe resulting mixture was stirred overnight
2. temperatureto slowly increase to room temperature
3. customThe reaction was partitioned between DCM and water
4. customthe organic layer was separated
5. washwashed with water
6. dry with materialdried (MgSO4)
7. concentrationconcentrated

ORD record

ord-0a20b7142b63460aa2268d1d645b03dd

Source dataset

uspto-grants-2012_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08329697B2