3-[3-(Trifluoromethoxy)phenyl]propanoic acid → 5-(Trifluoromethoxy)-2,3-dihydro-1H-inden-1-one
反応式
[F:1][C:2]([F:16])([F:15])[O:3][C:4]1[CH:5]=[C:6]([CH2:10][CH2:11][C:12]([OH:14])=O)[CH:7]=[CH:8][CH:9]=1>ClS(O)(=O)=O>[F:15][C:2]([F:1])([F:16])[O:3][C:4]1[CH:5]=[C:6]2[C:7](=[CH:8][CH:9]=1)[C:12](=[O:14])[CH2:11][CH2:10]2参加物
3
反応条件
- 温度
- 0 °C
実験手順
158e (9.0 g, 38.5 mmol) was added portionwise to chlorosulfonic acid (100 mL) while cooling with an iced bath. See FIG. 4. The resulting mixture was stirred at 0° C. for 1.5 h, poured into ice-water (1 L), and extracted with EtOAc (200 mL×3). The organic layers were dried over anhydrous sodium sulfate and concentrated. The residue was purified with by column chromatography on silica gel (ethyl acetate:petroleum ether=1:3) to afford 5-(trifluoromethoxy)-2,3-dihydro-1H-inden-1-one 158f (800 mg, 9.6%) as a yellow solid. 1H NMR (400 MHz, CDCl3): δ 7.72 (d, J=8.4 Hz, 1H), 7.24 (s, 1H), 7.14 (d, J=8.4 Hz, 1H), 3.11 (t, J=5.6 Hz, 2H), 2.69-2.66 (m, 2H).