【作者】 李万舜；

【导师】 刘玉鑫；

【作者基本信息】 四川大学 ， 应用化学， 2005， 硕士

【摘要】 本文在Dawson型杂多化合物P₂W₁₈ 和P₂W₁₆ 的基础上,通过取代和加成,合成出了6 种含一个铅原子以及不同数量钼原子的POM。通过IR、UV 等分析手段表征,证明它们保持了基本的Dawson型结构,利用TG 和EA 推断其为: K₁₀P₂W₁₆MoPbO₆₂ ·10H₂O 、K₈H₂P₂W₁₅Mo₂PbO₆₂ ·11H₂O 、K₁₀P₂W₁₄Mo₃PbO₆₂ ·10H₂O 、K₈H₂P₂W₁₃Mo₄PbO₆₂ ·8H₂O 、K₈H₂P₂W₁₂Mo₅PbO₆₂·9H₂O 和K₁₈[Pb(P₂W₁₆MoO₆₁)₂]·13H₂O。在水溶液中利用线性扫描极谱法研究6 种POM 的氧化还原性质,实验结果表明它们的氧化性质都与P₂W₁₈ 不同,特别是P₂W_（17-n）Mo_nPb（n =1～5）系列,其氧化性明显高于P2W18,并且随分子中钼含量的增高而增高。7 种POM 催化30%过氧化氢氧化环己烯为己二酸的实验表明P₂W_（17-n）Mo_nPb 系列有相近的催化效果（约73%）,且己二酸产率明显高于使用Pb(P₂W₁₆Mo)₂ 和P₂W₁₈ 时的情况;使用Pb(P₂W₁₆Mo)₂ 进行催化时的产率略低（约67.6%）但明显高于用做对比的P₂W₁₈（约60.7%）。本文探讨了温度、催化剂用量、反应时间以及H₂O₂ 与底物的摩尔比等条件对反应的影响,并优化了反应条件,确定了在环己烯用量10mmol 的情况下,较好的反应条件为:反应温度95℃,反应时间12h,P₂W₁₂Mo₅Pb0.01mmol,30%过氧化氢60mmol。此外,本文还对P₂W₁₂Mo₅Pb 在活性炭上进行了固载,在加入有机溶剂（t-BuOH）的情况下,用活性炭固载的P₂W₁₂Mo₅Pb 进行催化,产率可达72%,催化剂在重复使用6 次后性能未见明显下降。更多还原

【Abstract】 Six POM which contain one Pb and different number of Mo atoms have synthesized start from the well-known Dawson framework POM（P2W18 and P2W16）. The IR and UV indicate that all the 6 compounds still remain basically characteristic of the Dawson structure. The TG and EA suggest their molecular formulas are: K₁₀P₂W₁₆MoPbO₆₂ ·10H₂O 、K₈H₂P₂W₁₅Mo₂PbO₆₂ ·11H₂O 、K₁₀P₂W₁₄Mo₃PbO₆₂ ·10H₂O 、K₈H₂P₂W₁₃Mo₄PbO₆₂ ·8H₂O 、K₈H₂P₂W₁₂Mo₅PbO₆₂·9H₂O 和K₁₈[Pb(P₂W₁₆MoO₆₁)₂]·13H₂O。The studies on redox properties of these POM in aqueous solution were made by polarography. It is noteworthy that their oxidizing power are different to the P₂W₁₈,especially for the P₂W_（17-n）Mo_nPb（n =1～5） series. The oxidizing power of the series of POM is much strong than the P2W18,farthermore their oxidizing power increases as Mo atom number increase. Seven POM catalyze the oxidation of cyclohexene to adipic acid with 30% aqueous hydrogen peroxide, with P₂W_（17-n）Mo_nPb gave identical yields and performing much better than Pb(P₂W₁₆Mo)₂ and P₂W₁₈, Pb(P₂W₁₆Mo)₂ led to lower yields（around 67.6%） but much better than P₂W₁₈（around 60.7%）. The effects of temperature, catalyst loading, reaction time and molar ration of H₂O₂ to the substrate on the reaction were studied,and the reaction condition were optimized. When 10mmol cyclohexene been used, 95 ℃, 12h, 0.01mmol P₂W₁₂Mo₅Pb, and 60mmol 30% aqueous hydrogen peroxide is a better reaction condition. Activated carbon supported P2W12Mo5Pb catalyst were investigated, when organic solvents（t-BuOH） been used , Activated carbon supported P2W12Mo5Pb led to a high yields（around 72%）, and the yields have a very little decrease after the catalyst reuse 6 times.更多还原