[Cl:1][C:2]1[N:7]=[C:6]([O:8][C:9]2[CH:10]=[C:11]([CH:17]=[C:18]([CH3:20])[CH:19]=2)[CH2:12][O:13]C(=O)C)[C:5]([CH:21]([CH3:23])[CH3:22])=[C:4]([Cl:24])[N:3]=1.[OH-].[Li+]>C1COCC1>[Cl:1][C:2]1[N:7]=[C:6]([O:8][C:9]2[CH:10]=[C:11]([CH2:12][OH:13])[CH:17]=[C:18]([CH3:20])[CH:19]=2)[C:5]([CH:21]([CH3:22])[CH3:23])=[C:4]([Cl:24])[N:3]=1To a stirred solution of (4) (5 g, 13.54 mmol) in THF (20 ml) at room temperature, was added lithium hydroxide (649 mg, 27 mmol) followed by distilled water (20 ml). After stirring for 23 hr., THF was removed in vacuo and the residue was partitioned between dichloromethane and water. The organic layer was taken, dried with anhydrous magnesium sulfate, filtered, and evaporated in vacuo. The residue was purified by silica gel column chromatography (eluent, ether: hexanes (from 1:4 to 1:1)) to afford 2.92 g (66%) of a white solid; m.p. 140-141° C.; 1H NMR (200 MHz, CDCl3) δ 1.40 (6H, d, J=7.4 Hz), 1.76 (1H, t, J=5.6 Hz), 2.39 (3H, s), 3.58 (1H, m), 4.69 (2H, d, J=5.6 Hz), 6.84 (1H, s), 6.95 (1H, s), 7.09 (1H, s).
Loading…