[OH:1][C:2]1[CH:7]=[C:6]([OH:8])[CH:5]=[C:4]([OH:9])[C:3]=1[C:10](=[O:13])[CH2:11][CH3:12].[CH2:14](Br)[CH2:15][C:16]([CH3:18])=[CH2:17]>[OH-].[K+]>[OH:1][C:2]1[C:7]([CH2:14][CH:15]=[C:16]([CH3:18])[CH3:17])=[C:6]([OH:8])[C:5]([CH2:7][CH:2]=[C:3]([CH3:10])[CH3:4])=[C:4]([OH:9])[C:3]=1[C:10](=[O:13])[CH2:11][CH3:12]1-(2,4,6-trihydroxyphenyl)propan-1-one (2.0 g, 11.0 mmol) was dissolved in a 5% potassium hydroxide aqueous solution (20 mL). After the mixture was cooled below 0° C., isopentenyl bromide (3.3 g, 22 mmol) was slowly added dropwise within 30 min. The reaction mixture was stirred at room temperature for 2 hours, then poured into an ice water and acidified to pH 2. The reaction mixture was extracted with ethyl acetate. The extract was collected and dried over anhydrous sodium sulfate. After removal of solvent, The residue was purified by silica gel column chromatography (dichloromethane as eluent) to give the desired compound (0.63 g, yield 18%).
読み込み中…