反应详情

A mixture of methyl 2-(1-(3-hydroxyphenyl)-2-oxabicyclo[2.2.2]octan-4-yl)acetate (887 mg, 3.21 mmol), 3,4-dihydro-2H-pyran (0.5 ml, 5.47 mmol), and PPTS (81 mg, 0.321 mmol) in DCM (10 ml) was stirred at rt for 4 days. The reaction was concentrated in vacuo. The crude oil was purified by flash chromatography on SiO2 (0 to 30% EtOAc:hexanes) to afford the title compound (887 mg, 77% yield) as a white solid. LCMS, [M+NH4]+=378.4. 1H NMR (500 MHz, CDCl3) δ 7.21 (t, J=8.0 Hz, 1H), 7.13-7.08 (m, 1H), 6.99 (ddd, J=7.8, 1.5, 1.0 Hz, 1H), 6.93 (ddd, J=8.2, 2.5, 0.9 Hz, 1H), 5.43 (t, J=3.2 Hz, 1H), 3.97-3.86 (m, 3H), 3.67 (s, 3H), 3.64-3.54 (m, 1H), 2.17 (s, 2H), 2.11-1.96 (m, 5H), 1.90-1.74 (m, 6H), 1.72-1.49 (m, 3H).

1. concentrationThe reaction was concentrated in vacuo
2. customThe crude oil was purified by flash chromatography on SiO2 (0 to 30% EtOAc:hexanes)