[C:1]1(C)C=CC=CC=1.C1(C)C=CC(S([O-])(=O)=O)=CC=1.[NH+]1C=CC=CC=1.C([O:28][CH2:29][CH2:30][CH:31]1[CH2:35][CH2:34][CH2:33][C:32]1=[O:36])(=O)C>CO>[CH3:1][O:36][C:32]12[CH2:33][CH2:34][CH2:35][CH:31]1[CH2:30][CH2:29][O:28]2A reaction vessel was charged with 21 parts of anhydrous toluene, 0.6 parts of methanol, 0.2 part of pyridinium paratoluene sulfonate (PPTS), 2.0 parts of 2-(2-acetoxyethyl)cyclopentanone (8) obtained in Preparation Example 1 at room temperature. The mixture was refluxed for seven hours with stirring. After the reaction, the reaction mixture was filtered and the filtrate was concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (n-hexane: ethyl acetate=19:1) to obtain 1.6 parts of 1-methoxy-2-oxabicyclo[3.3.0]octane (9) (yield: 95%).
読み込み中…