Ethyl 4-hydroxybenzofuran-6-carboxylate → Ethyl 4-hydroxy-2,3-dihydrobenzofuran-6-carboxylate
反応式
[CH2:1]([O:3][C:4]([C:6]1[CH:14]=[C:13]([OH:15])[C:9]2[CH:10]=[CH:11][O:12][C:8]=2[CH:7]=1)=[O:5])[CH3:2]>C(O)(=O)C.[Pd]>[CH2:1]([O:3][C:4]([C:6]1[CH:14]=[C:13]([OH:15])[C:9]2[CH2:10][CH2:11][O:12][C:8]=2[CH:7]=1)=[O:5])[CH3:2]参加物
4
実験手順
Pd on carbon (100 mg) was added to a solution of 4-hydroxy-benzofuran-6-carboxylic acid ethyl ester (8a) (333 mg, 1.61 mmol) in acetic acid. The mixture was stirred under H2 (50 psi) for 48 hr. The mixture was filtered through Celite and concentrated. The residue was taken into saturated aqueous NaHCO3 and extracted with EtOAc. The organic layers were dried over MgSO4 and concentrated. The residue was purified by flash column chromatography eluting with 15% EtOAc in hexanes to give a pale yellow solid (315 mg, 94% yield). 1H NMR (400 MHz, CDCl3) δ 7.16 (d, J=1.26 Hz, 1 H) 7.05 (s, 1 H) 4.65 (t, J=8.72 Hz, 2 H) 4.35 (q, J=7.07 Hz, 2 H) 3.21 (t, J=8.72 Hz, 2 H) 1.38 (t, J=7.07 Hz, 3 H); LCMS for C11H12O4 m/z 209.10 (M+H)+.