过碳酸钠-醋酸酐作用下的Baeyer-Villiger反应

在醋酸酐介质中, 过碳酸钠可以与酮进行Baeyer-Villiger反应, 将它们氧化成相应的酯。其中脂环酮的反应结果较好, 环内酯的产率约为80%。芳香酮除芳环被活化的以外, 效果欠佳。当反应施加超声辐射后可显著加快反应速度, 并对过碳酸钠的作用机理进行了讨论。     

钨酸钠催化芳香腈高选择性氧化制备芳香酰胺

 The preparation of aryl amides by selective oxidation of aryl nitriles using sodium tungstate as catalyst and sodium percarbonate or sodium carbonate-hydrogen peroxide as the oxidant in a methanol and water solution was studied. Aryl nitriles were converted to aryl amides with very high selectivity of 95%～100% at room temperature. The reactivity of aryl nitriles decreased with increasing their branched chain length. In the oxidation of tolunitriles, the oxidation rate of p-tolunitrile and m-tolunitrile was very fast, but the oxidation rate of o-tolunitrile was very slow. The oxidation rate of p-haloid aryl nitriles and p-nitro aryl nitrile decreased in the order p-nitrobenzonitrile＞p-chlorobenzonitrile＞p-bromobenzonitrile, while the selectivity for aryl amides was maintained at a high level of 98%～100%. The comparison of the two oxidants showed that when sodium carbonate-hydrogen peroxide was used as oxidant, the oxidation rate and selectivity were better than that when percarbonate was used. The sodium tungstate catalyst and carbonate can be reused and the catalytic activity and selectivity did not change if a suitable amount of hydrogen peroxide was supplied. This work provides a convenient method for the preparation of aryl amides from aryl nitriles under very mild reaction conditions.     

研究型实验活动——设计与制作家用制氧机

氧立得制氧机是当前家庭用于缺氧预防和治疗的主要设备之一,具有制氧纯、产氧足、供氧快、易携带、操作简单等特点。剖析了氧立得制氧机的反应原理和产品结构,探究了过碳酸钠的制氧性质,通过与过氧化氢的制氧效果进行对比,揭示了实际应用中制氧剂的选择依据。自主设计并制作了简易制氧机,分析了真实制氧机的产品形成与加工设计思路,从而培养学生工程技术素养,为教师教学提供借鉴。     

真实情境推动下的大单元教学设计与实践*——以“过碳酸钠专题复习”为例

以“过碳酸钠专题复习”的大单元教学为例,从情境选择、内容确定、单元目标、活动设计等方面阐述中考复习阶段通过“单元设计”教学中情境化的教学设计、多样化的教学方式与科学化的教学评价,高效践行立德树人的素质教育以及学以致用、知行合一的真实学习。     

过碳酸钠对三苯甲烷染料的降解行为研究

以过碳酸钠为氧化剂,考察了其对孔雀石绿、灿烂绿、碱性品红及结晶紫四种三苯甲烷类染料的降解行为。结果表明:在pH=11、温度为20℃、过碳酸钠的浓度为10mg/L、降解时间为20min时,过碳酸钠对灿烂绿的脱色率可达到95%。通过比较四种染料的脱色效果,均显示了良好的脱色能力,说明过碳酸钠是一种广谱的三苯甲烷类染料的良好脱色剂。在此基础上,对灿烂绿的脱色机理进行了初步探讨。