[OH:1][C:2]1[CH:11]=[C:10]([OH:12])[CH:9]=[C:8]2[C:3]=1[C:4](=[S:14])[CH:5]=[C:6]([CH3:13])[O:7]2.C(=O)([O-])[O-].[K+].[K+].[CH:21](I)([CH3:23])[CH3:22].[CH3:25]I>O.CC(C)=O>[CH:21]([O:12][C:10]1[CH:9]=[C:8]2[C:3]([C:4](=[S:14])[CH:5]=[C:6]([CH3:13])[O:7]2)=[C:2]([O:1][CH3:25])[CH:11]=1)([CH3:23])[CH3:22]
354 mg of 5,7-dihydroxy-2-methylthiochromone (1.58 mmol), 1.09 g of potassium carbonate (7.90 mmol), 0.79 ml isopropyl iodide (7.90 mmol) and 20 ml acetone were refluxed overnight. After addition of 2.95 ml methyl iodide (47.4 mmol), the mixture was further refluxed overnight. Following addition of water, the reaction solution was extracted twice with ethyl acetate, and the organic layer was washed with saturated NaCl water and dried over sodium sulfate anhydride. The solvent was distilled off under reduced pressure, and the crude product was purified by flash column chromatography (hexane: ethyl acetate =1 : 3→1:6), to give 228 mg of 7-isopropoxy-5-methoxy-2-methylthiochromone (52% yield).
読み込み中…
