反应详情

温度

-78 °C

In 200 mL of ether, was dissolved 13.6 g (85.9 mmol) of 2-trimethylsilyloxy-2-pentene, and 4.6 mL (47.3 mmol) of malonyl chloride was added dropwise to the solution while stirring the solution at −78° C. After the addition of malonyl chloride, the solution was stirred for 1 hour at −78° C., and then, stirred over night while gradually heating the solution to room temperature. The precipitate was filtered and washed with ether. As a result, 3.08 g (20.0 mmol, 42.3%) of 5-ethyl-4-hydroxy-6-methyl-2-pyrone was obtained.

1. additionwas added dropwise to the solution
2. stirringthe solution was stirred for 1 hour at −78° C.
3. stirringstirred over night
4. temperaturewhile gradually heating the solution to room temperature
5. filtrationThe precipitate was filtered
6. washwashed with ether