Iodine → (3aR,6aR)-5-iodo-2,2-dimethyl-3aH-cyclopenta[d][1,3]dioxol-4(6aH)-one

関与物質

反応手順

3aR,6aR)-2,2-dimethyl-3aH-cyclopenta[d][1,3]dioxol-4(6aH)-one (5-1) (1.2 g, 7.8 mmol, 1 equiv) was dissolved in DCM (50 mL) and pyridine (0.9 mL, 10.9 mmol, 1.4 equiv) was added followed by a solution of iodine (3.4 g, 13.2 mmol, 1.7 equiv) in THF (6 mL). The resulting mixture stirred overnight at ambient temperature. Upon disappearance of starting material, the reaction mixture was poured over water (30 mL), extracted with CHCl3 (3×50 mL), dried over MgSO4, filtered and concentrated. The crude residue was purified by flash chromatography (80 g SiO2, 0-40% EtOAc in hexanes) to yield (3aR,6aR)-5-iodo-2,2-dimethyl-3aH-cyclopenta[d][1,3]dioxol-4(6aH)-one (5-2) as a pale yellow solid. 1H NMR (500 MHz, CDCl3): δ 7.97 (d, J=2.5 Hz, 1H); 5.22 (dd, J=5.5, 2.5 Hz, 1H); 4.53 (d, J=5.5 Hz, 1H); 1.42 (s, 3H); 1.39 (s, 3H).

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