Ethylene Glycol → 5-(2-Ethyl-1,3-dioxolan-2-yl)benzofuran

反応式

[O:1]1[C:5]2[CH:6]=[CH:7][C:8]([C:10](=[O:13])[CH2:11][CH3:12])=[CH:9][C:4]=2[CH:3]=[CH:2]1.[CH2:14](O)[CH2:15][OH:16].CC1C=CC(S(O)(=O)=O)=CC=1>C1(C)C=CC=CC=1>[CH2:11]([C:10]1([C:8]2[CH:7]=[CH:6][C:5]3[O:1][CH:2]=[CH:3][C:4]=3[CH:9]=2)[O:16][CH2:15][CH2:14][O:13]1)[CH3:12]

参加物

実験手順

A solution of 1-(benzofuran-5-yl)propan-1-one (650 mg, 1.0 eq), ethane-1,2-diol (3.5 g, 15.0 eq) and 4-methylbenzenesulfonic acid (65 mg, 0.1 eq) in 20 mL toluene was refluxed for 72 h, cooled, quenched with sat. NaHCO3 (aq) and extracted with EtOAc. The extract was washed with brine, dried, concentrated, and purified by column chromatography to give the desired product (710 mg, 87%). 1H NMR (400 MHz, CDCl3) δ 7.69 (d, J=2.0 Hz, 1H), 7.62 (d, J=2.4 Hz, 1H), 7.45 (d, J=8.4 Hz, 1H), 7.39 (dd, J=8.4 Hz, 1.6 Hz, 1H), 6.76 (dd, J=2.4 Hz, 0.4 Hz, 1H), 4.02-4.05 (m, 2H), 3.78-3.81 (m, 2H), 1.96 (q, J=7.2 Hz, 2H), 0.89 (t, J=7.2 Hz, 3H).