A preparing method of acacetin

A preparing method of acacetin is disclosed. The method includes subjecting a compound 2 and a compound 3 to a cyclization reaction under the existence of a catalyst, wherein the catalyst is one or more selected from 4-dimethylaminopyridine, 4-pyrrolidinopyridine and tri-n-butylphosphine, and the reaction is performed at 150-200 DEG C. The method is high in yield, low in cost, simple in operation and suitable for industrial production. 本发明公开了种金合欢素的制备方法，其包括如下步骤：在催化剂存在下，将化合物2和化合物3进行成环反应，即得；所述的催化剂为4-二甲氨基吡啶、4-吡咯烷基吡啶和三正丁基膦中的种或多种；所述的反应的温度为150℃～200℃。本方法收率高、成本低、操作简单，适于工业化生产。