C[Si]([N-][Si](C)(C)C)(C)C.[Li+].Cl[CH2:12][C:13](=[CH2:36])[CH2:14][O:15][C:16]1[CH:25]=[CH:24][C:19]([C:20]([O:22][CH3:23])=[O:21])=[CH:18][C:17]=1[CH2:26][S:27]([C:30]1[CH:35]=[CH:34][CH:33]=[CH:32][CH:31]=1)(=[O:29])=[O:28].O.Cl>O1CCCC1.ClCCl>[CH2:12]=[C:13]1[CH2:36][CH:26]([S:27]([C:30]2[CH:35]=[CH:34][CH:33]=[CH:32][CH:31]=2)(=[O:29])=[O:28])[C:17]2[CH:18]=[C:19]([C:20]([O:22][CH3:23])=[O:21])[CH:24]=[CH:25][C:16]=2[O:15][CH2:14]11.33 ml of 1.06M lithium bis(trimethylsilyl)amide in tetrahydrofuran are added to 478 mg (1.21 mmol) of methyl 4-{[2-(chloromethyl)-2-propenyl]oxy}-3-[(phenylsulfonyl)methyl]benzoate dissolved in 39 ml of tetrahydrofuran. The solution is stirred for 5 minutes and then water, 1N hydrochloric acid and dichloromethane are added to the reaction medium. After separating, the aqueous phase is extracted three times with dichloromethane. The combined organic phases are washed with brine, dried and then concentrated under vacuum. The crude reaction product is purified by chromatography on silica gel (ethyl acetate/heptane 40/60) to provide 259 mg (60%) of methyl 3-methylene-5-(phenylsulfonyl)-2,3,4,5-tetrahydro-1-benzoxepin-7-carboxylate in the form of a white solid; 1H NMR (300 MHz, CDCl3): 2.98 (dd, J=13.9 and 7.1 Hz, 1H), 3.21 (dd, J=13.9 and 7.1 Hz, 1H), 3.86 (s, 3H), 4.20 (d, J=13.4 Hz, 1H), 4.45 (t, J=7.35 Hz, 1H), 4.73 (d, J=13.4 Hz, 1H), 4.99 (s, 1H), 5.09 (s, 1H), 6.98 (d, J=8.28 Hz, 1H), 7.43 (m, 2H), 7.62 (m, 3H), 7.76 (d, J=2.07 Hz, 1H), 7.94 (dd, J=8.46 and 2 Hz, 1H).
読み込み中…