钨酸/无机酸性配体催化氧化环己烯合成己二酸

以钨酸／无机酸性配体为催化体系,在无有机溶剂和相转移剂的情况下,催化过氧化氢(质量分数30％)氧化环己烯合成己二酸。结果表明,以钨酸／磷酸催化氧化环己烯的催化效果最优。当钨酸:无机酸性配体:环己烯:过氧化氢的摩尔比为1:1:40:176,反应8 h时,己二酸产率达88.2％且纯度高;而不使用无机酸性配体时,己二酸产率只有72.1％,产品纯度也较低。当使用磷酸、硼酸为无机酸性配体时,随反应时间的增加,己二酸产率均升高。当磷酸用量为2.5 mmol时,己二酸产率和纯度均较高。

Direct catalytic oxidation of cyclohexene to adipic acid by tungstenic acid/inorganic acidic ligand

In the absence of organic solvent and phase-transfer catalyst, the catalytic oxidation of cyclohexene to adipic acid with aqueous 30% hydrogen peroxide by weight can be efficiently catalyzed by tungstenic acid/inorganic acidic ligand. The results showed that tungstenic acid/phosphoric acid used as a catalyst offered the best catalytic effect for cyclohexene oxidation. The yield of adipic acid was 88. 2% with high purity in 8 h when the mole ratio of tungstenic acid : acidic inorganic ligand : cyclohexene:hydrogen peroxide was 1:1:40:176. The yield of adipic acid was only 72. 1% with low purity using tungstenic acid as a catalyst alone, but increased while prolonging the reaction time with phosphoric acid and boric acid used as ligands. The adipic acid had high yield and purity at phosphoric acid amount of 2.5 mmol.