反应详情

温度

0 °C

Dihydropyran (9.1 ml, 100 mmol) was added dropwise to a cooled (0° C.) solution of 2-butene-1,4-diol (8.8 g, 10 mmol) and pyridinium paratoluenesulfonate (0.25 g, 10 mmol) in anhydrous dichloromethane:tetrahydrofuran (2:1). The mixture was stirred two days at 0° C. then concentrated in vacuo. The residue was purified by flash chromatography on silica gel (ethyl acetate:hexane 3:7) to give 8.3 g of the title compound (49%).

1. concentrationthen concentrated in vacuo
2. customThe residue was purified by flash chromatography on silica gel (ethyl acetate:hexane 3:7)