Trifluoroacetic acid → 2-(4-Fluorophenyl)chroman-6-ol

反応式

C([SiH](CC)CC)C.[F:8][C:9]1[CH:14]=[CH:13][C:12]([CH:15]2[CH2:24][CH:23](O)[C:22]3[C:17](=[CH:18][CH:19]=[C:20]([OH:26])[CH:21]=3)[O:16]2)=[CH:11][CH:10]=1.FC(F)(F)C(O)=O>ClCCl>[F:8][C:9]1[CH:14]=[CH:13][C:12]([CH:15]2[CH2:24][CH2:23][C:22]3[C:17](=[CH:18][CH:19]=[C:20]([OH:26])[CH:21]=3)[O:16]2)=[CH:11][CH:10]=1

参加物

実験手順

Triethylsilane (14 ml) was added slowly into a solution of 2-(4-fluorophenyl)chroman-4,6-diol (2.9 g) in dichloromethane (58 ml). Trifluoroacetic acid (27 ml) was then added dropwise into a reaction mixture and it was stirred at room temperature for 1 hour. The reaction mixture was poured on ice-water and extracted with dichloromethane. The residue was evaporated under reduced pressure with toluene to obtain 2-(4-fluorophenyl)chroman-6-ol. 1H NMR (400 MHz, CDCl3) δ: 7.38 (m, 2H), 7.06 (m, 2H), 6.77 (d, 1H, J 8.6 Hz), 6.61 (dd, 1H, J 8.6, 2.9 Hz) 6.57 (d, 1H, 8.6 Hz), 4.97 (dd, 1H, J 10.2, 2.4 Hz), 2.95 (ddd, 1H, J −16.8, 11.4, 6.2 Hz), 2.74 (ddd, 1H, J −16.8, 5.3, 3.1 Hz), 2.15 (m, 1H), 2.05 (m, 1H).