反应详情

Ethyl 2-ethyl-4-methylenecyclopentanecarboxylate (0.720 g, 3.95 mmol), triphenylsilanethiol (1.329 g, 4.54 mmol) and 2,2′-azobis(2-methylpropionitrile) (0.195 g, 1.185 mmol) in toluene (3.95 mL) was heated at reflux for about 6 h. The reaction mixture was cooled to ambient temperature and then concd under reduced pressure. The material was purified by silica gel (40 g) chromatography eluting with a gradient of 0-10% EtOAc in heptane to give a colorless oil. The resulting oil was dissolved in DCM (4 mL) and TFA (1.52 mL, 19.7 mmol) was added. After stirring at ambient temperature for about 1 h, the solvent was removed under reduced pressure. The material was purified by silica gel (40 g) chromatography eluting with a gradient of 0-15% EtOAc in heptane to provide ethyl 2-ethyl-4-(mercaptomethyl)cyclopentanecarboxylate (0.620 g, 72%) as a colorless oil: 1H NMR (DMSO-d6) δ 4.13-4.01 (m, 2H), 2.50-2.30 (m, 3H), 2.24 (m, 1H), 2.15-1.87 (m, 3H), 1.66-1.54 (m, 1H), 1.50-1.37 (m, 2H), 1.31-1.23 (m, 2H), 1.17 (t, 3H), 0.83 (m, 3H).

1. temperatureat reflux for about 6 h
2. customThe material was purified by silica gel (40 g) chromatography
3. washeluting with a gradient of 0-10% EtOAc in heptane
4. customto give a colorless oil
5. customthe solvent was removed under reduced pressure
6. customThe material was purified by silica gel (40 g) chromatography
7. washeluting with a gradient of 0-15% EtOAc in heptane