A Novel Ternary Composite of Polyurethane/Polyaniline/Nanosilica with Antistatic Property and Excellent Mechanical Strength: Preparation and Mechanism

Chinese Journal of Polymer Science - Antistatic and strength properties are of vital importance for polyurethane rubber used in moving parts of many industrial instruments. Herein, polyurethane was...     

羧甲基纤维素支载三亚乙基四胺催化Knoevenagel反应

烯烃;羧甲基纤维素支载三亚乙基四胺催化Knoevenagel反应     

Synthesis of Aryl Allyl Ether in the Recyclable Ionic Liquid [bmim]PF_6

Ionic liquids, especially imidazonium salts, have recently gained recognition as possible environmentally benign alternative chemical process solvents. This is mainly due to their nonvolatile nature, insolubility in some solvents as well as their ability to dissolve a wide range of organic and inorganic materials, allowing the ionic liquids easy recovery and recycling. Examples of their application in organic reactions have been summarized in a number of recent review articles. 1 Aryl allyl et…     

Liquid Chromatography of Aspirin,Salicylic Acid and Acetic Acid on Cation Exchange Resin

A 8% cross-linked sulfonated polystyrene cation exchanger in the hydrogen or sodium form was used as stationary phase for the chromatography of aspirin, salicylic acid and acetic acid. The eluent is 0.02 M mineral acids or their sodium salts in aqueous ethanol. Phosphoric acid, nitric acid or sulfuric acid added in aqueous ethanol eluent made successful separation of aspirin, salicylic acid and acetic acid on hydrogen form cation exchanger.     

离子液体促进四氟硼酸铜催化芳醛和乙酸酐合成1,1-二乙酸酯

在室温条件下, 离子液体1-正丁基-3-甲基六氟磷酸盐([bmim]PF₆)能促进四氟硼酸铜催化一系列芳醛和乙酸酐反应, 以83%～97%的产率生成相应的1,1-二乙酸酯. 在离子液体[bmim]PF₆存在情况下, 催化剂活性远远高于无离子液体存在下的活性. 催化剂用量仅需 0.2 mol%就能使反应顺利进行, 远远少于文献报道的其它催化剂的用量, 反应在3～20 min内完成. 实验结果表明该法催化剂用量少、产率高、反应时间短、离子液体可重复使用、对环境友好.     

基于认知逻辑的“质量守恒定律”教学分析

以化学发展史中质量守恒定律的认知逻辑为视角,分析了学生学习质量守恒定律的认知障碍,并通过问卷测试进行了实证,提出了基于“问题解决”的教学设计建议,为有效课堂教学提供参考。     

含氮鎓阴离子受体的研究进展

含氮鎓阴离子受体是目前阴离子识别领域研究的热点之一,此类受体具有主体结构修饰的灵活性和多样性,能更好的发挥氢键、疏水作用、静电作用、π-π作用、阴离子-π作用的协同效应等优点。本文详细评述了咪唑鎓和吡啶鎓两类含氮鎓受体的设计、结构及其阴离子识别作用的研究进展。     

A one-pot multicomponent reaction for the synthesis of 2-amino-2-chromenes promoted by <Emphasis Type="Italic">N,N</Emphasis>-dimethylamino-functionalized basic ionic liquid catalysis under solvent-free condition

Abstract  A simple, clean, and environmentally benign three-component process to the synthesis of 2-amino-4H-chromenes using N,N-dimethylaminoethylbenzyldimethylammonium chloride, [PhCH₂Me₂N⁺CH₂CH₂NMe₂]Cl⁻, as an efficient catalyst under solvent-free condition is described. A wide range of aromatic aldehydes easily undergo condensations with α-naphthol and malononitrile under solvent-free condition to afford the desired products of good purity in excellent yields. Taking into account environmental and economical considerations, the protocol presented here has the merits of environmentally benign, simple operation, convenient work-up and good yields. Furthermore, the catalyst can be easily recovered and reused for at least five cycles without losing its activities. Graphical abstract        

A one-pot multicomponent reaction for the synthesis of 2-amino-2-chromenes promoted by N,N-dimethylamino-functionalized basic ionic liquid catalysis under solvent-free condition

Abstract  

A simple, clean, and environmentally benign three-component process to the synthesis of 2-amino-4H-chromenes using N,N-dimethylaminoethylbenzyldimethylammonium chloride, [PhCH₂Me₂N⁺CH₂CH₂NMe₂]Cl⁻, as an efficient catalyst under solvent-free condition is described. A wide range of aromatic aldehydes easily undergo condensations with α-naphthol and malononitrile under solvent-free condition to afford the desired products of good purity in excellent yields. Taking into account environmental and economical considerations, the protocol presented here has the merits of environmentally benign, simple operation, convenient work-up and good yields. Furthermore, the catalyst can be easily recovered and reused for at least five cycles without losing its activities.