Toluene is used as azeotrope in the preparation of ketal.

缩酮制备时，采用甲苯为共沸剂；

Cyclopentanone ethylene ketal was synthesized with I_2 as catalyst.

以单质碘为催化剂合成了环戊酮乙二缩酮。

The invention relates to garland chrysanthemum extract compounds, and a synthesis method and application thereof. The compounds have enol ether-spiro ketal-acetals and unsaturated side chains.

本发明茼蒿素类化合物及其合成方法与应用，该化合物具有烯醇醚-螺环缩酮-缩醛和不饱和侧链。