Cyclopentanol → (2-Cyclopentyloxy-5-oxo-tetrahydro-furan-3-yl)-carbamic acid allyl ester
反応式
C([O:5][C:6](=[O:18])[CH2:7][CH:8]([NH:11][C:12]([O:14][CH2:15][CH:16]=[CH2:17])=[O:13])[CH2:9][OH:10])(C)(C)C.[CH:19]1(O)[CH2:23][CH2:22][CH2:21][CH2:20]1>>[CH2:15]([O:14][C:12](=[O:13])[NH:11][CH:8]1[CH2:7][C:6](=[O:5])[O:18][CH:9]1[O:10][CH:19]1[CH2:23][CH2:22][CH2:21][CH2:20]1)[CH:16]=[CH2:17]参加物
3
実験手順
Prepared from 3-allyloxycarbonylamino-4-hydroxy-butyric acid tert-butyl ester as described for 40 using cyclopentanol to afford the title compound as a mixture of diastereomers. Flash column chromatography using hexanes/EtOAc (90/10 to 80/20) afforded the syn diastereomer of the title compound: syn diastereomer 1H NMR (500 MHz, CDCl3) δ 1.5-2.0 (m, 8H), 2.45 (dd, 1H), 2.81 (dd, 0.9H), 3.0 (dd, 0.1H), 4.31 (m, 1H), 4.59 (m, 4H), 5.23 (m, 1H), 5.32 (m, 1H), 5.45 (s, 0.1H), 5.51 (s, 0.9H), 5.92 (m, 1H) ppm; anti diastereomer 1H-NMR (500 MHz, CDCl3) δ 1.50 (m, 2H), 1.67 (m, 6H), 2.36 (d, 1H), 2.8 (dd, 0.08H), 2.96 (dd, 0.92H), 4.13 (m, 1H), 4.25 (m, 1H), 4.55 (br, 2H), 5.20 (d, 1H), 5.30 (m, 2H), 5.43 (s, 0.92H), 5.5 (d, 0.08H), 5.89 (s, 1H) ppm.