重氮甲烷 、 4-chloro-5-hydroxy-(3-phenylprop-2(E)-en-1-ylidene)cyclopent-4-en-1,3-dione 以
乙醚 为溶剂,
生成
4-chloro-5-methoxy-2(E)-(3-phenylprop-2(E)-en-1-ylidene)cyclopent-4-en-1,3-dione 、 4-chloro-5-methoxy-2(Z)-(3-phenylprop-2(E)-en-1-ylidene)cyclopent-4-en-1,3-dione