Ullmann法合成氧杂蒽酮的研究

Synthesis of Xanthone by Approach of Ullmann

以2-氯苯甲酸和苯酚为原料,先经过Ullmann缩合反应制得2-苯氧基苯甲酸,再在三氯氧磷作用下脱水环合得到氧杂蒽酮。合成中间体产物的最佳条件是:n(2-氯苯甲酸)∶n(苯酚)∶n(碳酸钾)∶n(氧化铜)为1∶6∶1.5∶0.06。该方法具有操作简便、条件温和、环境友好等优点,氧杂蒽酮总产率有63.84%。

Xanthone was prepared by the Ullmann condensation of 2-chlorobenzoic acid and phenol followed by dehydration ring closure in the presence of phosphorus oxychloride. The optimum reaction conditions for the intermediate product were as follows.the reaction time of 2 h and n（2-chlorobenzoic acid）：n（phenol） ： n（potassium carbonate）：n（cupric oxide）=1：6：1.5：0.06. The reactions were run under mild conditions and they were environmentally friendly. The overall yeild of xanthone was 63.84 %.