磷钼酸盐作为反应控制相转移催化剂催化氧化醇

以磷钼酸盐C₇H₇N(CH₃)₃]₃{PO₄MoO(O₂)₂]₄}为反应控制相转移催化剂, 用过氧化氢水溶液为氧化剂, 在液相选择性氧化醇制备醛的反应中, 发现该催化剂具有良好的催化活性. 在H₂O₂与醇的物质的量比为0.75的条件下, 产物中未检测到任何副产物, 基于H₂O₂的醇转化率最高达到95.2%. 反应结束时, 催化剂以沉淀的形式析出, 回收率不低于78%. 以苯甲醇的氧化为探针反应, 详细考察催化剂的反荷阳离子和溶剂种类对反应控制相转移现象和催化活性的影响. 结果表明, 选择 C₇H₇N(CH₃)₃]^＋作为反荷阳离子和乙腈为溶剂, 体系出现了反应控制相转移催化的特征. 催化剂循环使用三次, 在保持较高回收率的同时其催化活性无明显降低, 说明该催化剂具有良好的稳定性.

Oxidation of Alcohol with Phosphomolybdate as Reaction-controlled Phase-transfer Catalyst

Phosphomolybdate C7H7N(CH3)33{PO4MoO(O2)24} was applied to the oxidation of alcohols with hydrogen peroxide as the oxidant and high efficient catalytic performance was achieved. When the mo-lar ratio of H2O2 to alcohol was 0.75,no other by-product was detected by gas chromatography,and the conversion of alcohol based on H2O2 reached 95.2%. Once H2O2 was used up,the catalyst could be recycled from the system easily as deposit,and the catalyst recovery ratios were not less than 78%. The effect of various parameters on the conversion of benzyl alcohol was studied,such as countercation of the catalyst and solvent. The results indicate that choosing C7H7N(CH3)3 as the countercation and acetonitrile as the solvent,the system shows the feature of reaction-controlled phase-transfer catalysis. Under the conditions,the results of the recycling of the catalyst indicate that the catalyst exhibits high stability.