4-Bromobutyric acid → 4-Bromobutanoic Acid 9-Fluorenylmethyl Ester

反応式

[Br:1][CH2:2][CH2:3][CH2:4][C:5]([OH:7])=[O:6].[CH:8]1[C:20]2[CH:19]([CH2:21]O)[C:18]3[C:13](=[CH:14][CH:15]=[CH:16][CH:17]=3)[C:12]=2[CH:11]=[CH:10][CH:9]=1>CN(C)C1C=CN=CC=1.C(Cl)Cl>[CH:8]1[C:20]2[CH:19]([CH2:21][O:6][C:5](=[O:7])[CH2:4][CH2:3][CH2:2][Br:1])[C:18]3[C:13](=[CH:14][CH:15]=[CH:16][CH:17]=3)[C:12]=2[CH:11]=[CH:10][CH:9]=1

参加物

実験手順

DDC (6.00 g, 29 mmol) was added in one portion to a cooled solution (0° C.) of 4-bromobutyric acid (5.00 g, 29.9 mmol), 4-(dimethylamino)pyridine (353 mg, 2.9 mmol) and 9-fluorenemethanol (5.63 g, 25 mmol) in CH2Cl2 (150 mL). The mixture was allowed to stand at 4° C. for 18 h, and then filtered. The filtrate was evaporated to dryness under reduced pressure. The residue was dissolved in EtOAc and the solution washed sequentially with 1N NaHCO3, 1N HCl and H2O. The solution was dried (Na2 -SO4) and evaporated to dryness under reduced pressure. The residue was purified by flash chromatography on silica gel (200 g) using hexane-EtOAc (15:1) as the eluant to give the pure title compound as an oil (7.5 g).