反应详情

To a solution of compound 22 (35 mg, 0.12 mmol) in DMSO (3 mL) was added trimethylsulfonium iodide (204 mg, 1.0 mmol) and potassium tert-butoxide (112 mg, 1.0 mmol) at room temperature. After 3 h, water (20 mL) was added and the product extracted into EtOAc (50 mL×3). The combined extracts were dried, filtered and concentrated. The residue was purified by flash column chromatography (silica gel eluted with 20% EtOAc in hexanes) to afford compound 23 (23 mg, 63%): mp 138-140° C.; [α]D20 −16.7 (c 0.15, CHCl3); 1H NMR (CDCl3) δ 4.06 (s, br, 1H), 2.90 (d, J=5.1 Hz, 1H), 2.61 (d, J=5.1 Hz, 1H), 0.86 (s, 3H), 0.79 (s, 3H); 13C NMR (CDCl3) δ 70.5, 66.6, 54.6, 53.6, 47.1, 42.6, 40.2, 39.2, 36.4, 35.8, 35.1, 32.0, 31.8, 29.1, 28.9, 28.8, 25.9, 24.4, 14.4, 11.2; IR νmax 3435, 1007, 758 cm−1. Anal. Calcd for (C20H32O2): C, 78.90; H, 10.59. Found: C, 78.83; H, 10.77.

1. extractionthe product extracted into EtOAc (50 mL×3)
2. customThe combined extracts were dried
3. filtrationfiltered
4. concentrationconcentrated
5. customThe residue was purified by flash column chromatography (silica gel eluted with 20% EtOAc in hexanes)