反应详情

Sodium hydride (665 mg, 17 mmol, washed three times with hexane) was treated with the title product of Example 3 (2.0 g, 14 mmol) in 90 mL of tetrahydrofuran at reflux for one hour. A solution of 5-bromopentene (2.0 g, 14 mmol) in 50 mL of tetrahydrofuran was added dropwise and refluxing continued for 20 hours. After cooling to room temperature, 50 mL of water was added, the layers separated and-the aqueous phase was extracted with two portions of ethyl acetate. The combined organic extracts were washed with brine, dried over magnesium sulfate, filtered and concentrated. Chromatography of the crude residue on silica gel using 50-50 ethyl acetate-heptane as eluant gave the title compound (485 mg) as a yellow oil and the structure verified by NMR.

1. temperatureat reflux for one hour
2. temperaturerefluxing
3. customthe layers separated
4. extraction-the aqueous phase was extracted with two portions of ethyl acetate
5. washThe combined organic extracts were washed with brine
6. dry with materialdried over magnesium sulfate
7. filtrationfiltered
8. concentrationconcentrated