反应详情

To a suspension of the phosphonium salt (90.2 g, 1.5 eq) in dry THF (1100 mL) at 0° C. under nitrogen atmosphere was added n-BuLi (2.5 M, 216 mL, 0.54 mol). The solution was stirred for 1 h, followed by addition of dihydro-2H-pyran-4(3H)-one (15 g, 0.15 mol). Stirring was continued at rt overnight. The mixture was quenched with satd aq NH4Cl, and then filtered. The filtrate was dried over Na2SO4, and concentrated under vacuum to give the crude product, which was purified by column chromatography to give the product (13.1 g, 61%). 1H NMR (CD3OD) δ 2.1-2.3 (m, 6H), 2.5 (s, 1H), 3.5-3.7 (m, 6H), 5.1-5.2 (t, 1H).

1. stirringStirring
2. waitwas continued at rt overnight
3. customThe mixture was quenched with satd aq NH4Cl
4. filtrationfiltered
5. dry with materialThe filtrate was dried over Na2SO4
6. concentrationconcentrated under vacuum
7. customto give the crude product, which
8. customwas purified by column chromatography