Lithium Bromide → HCID 66917128、化合物
反応式
[CH3:1][C:2]1([CH3:23])[O:6][C@H:5]([CH2:7][O:8][C:9]2[CH:14]=[CH:13][C:12]([CH2:15][CH2:16][CH2:17]OS(C)(=O)=O)=[CH:11][CH:10]=2)[CH2:4][O:3]1.[Br-:24].[Li+]>CC(C)=O>[Br:24][CH2:17][CH2:16][CH2:15][C:12]1[CH:13]=[CH:14][C:9]([O:8][CH2:7][C@@H:5]2[CH2:4][O:3][C:2]([CH3:23])([CH3:1])[O:6]2)=[CH:10][CH:11]=1参加物
4
実験手順
Methanesulfonic acid 3-[4-((R)-2,2-dimethyl[1,3]dioxolan-4-ylmethoxy)-phenyl]-propylester (11.8 g, 34.2 mmol) in acetone (200 ml) is treated with lithium bromide (8.9 g, 100 mmol) and then heated at reflux for 5 h. After cooling to room temperature, the mixture is concentrated in vacuo. The resulting residue is dissolved in EtOAc (150 ml), washed with water (2×50 ml), brine, dried (MgSO4), filtered and concentrated in vacuo to give an oil. Purification by chromatography on silica eluting with 4:1 iso-hexane/EtOAc gives (R)-4-[4-(3-Bromo-propyl)-phenoxymethyl]-2,2-dimethyl-[1,3]dioxolane as a colourless oil which solidifies; 1H NMR (CDCl3): 1.39 (3H, s), 1.43 (3H, s), 2.02 (2H, pent, J=6.9 Hz), 2.63 (2H, tr, J=6.9 Hz), 3.38 (2H, tr, J=6.9 Hz), 3.90 (2H, m), 4.02 (1H, m), 4.15 (1H, m), 4.46 (1H, pent, J=6.9 Hz), 6.82 (2H, d, J=7.4 Hz), 7.10 (2H, d, J=7.4 Hz).