辐照环己基苯基酮(1)导致分子内或分子间夺氢,从而得到化合物1-苯基庚6烯-1-酮(2)和α-环己基苄醇(3)作为光产物,其中3具有一对对映体。在此,制备两种类型的手性六方液晶的直接的对映光化学反应1。六边形液晶之一是由1-十四烷基-3-甲基咪唑鎓溴化物/对二甲苯/ H 2 O组成,并经手性电感剂修饰。另一个由手性(S)-3-十六烷基-1-(1-羟基丙-2-基) -咪唑溴化物/ p二甲苯/ H 2 O的产物的分析表明,后者可被用作微反应器,以实现立体选择性的光化学反应,而前者所产生的化合物3完全没有对映选择性。
Stabilisation of gold nanoparticles by N-heterocyclic thiones
作者:Leonardo C. Moraes、Bertrand Lacroix、Rute C. Figueiredo、Patricia Lara、Javier Rojo、Salvador Conejero
DOI:10.1039/c7dt01856h
日期:——
Gold nanoparticles (Au-NPs) have been prepared using N-heterocyclic thiones (NHTs) as ligand stabilisers. These Au-NPs have been shown to be very stable, even in air, and have been characterized by a combination of several techniques (TEM, HR-TEM, STEM-HAADF, EDX, DLS, elemental analysis and 1H NMR). These nanoparticles are active in the catalytic reduction of nitroarenes to anilines.
金纳米颗粒(Au-NPs)已使用N-杂环硫酮(NHTs)作为配体稳定剂制备。这些Au-NP甚至在空气中也显示出非常稳定的特性,并且已通过多种技术(TEM,HR-TEM,STEM-HAADF,EDX,DLS,元素分析和1 H NMR)的组合进行了表征。这些纳米颗粒在将硝基芳烃催化还原成苯胺中具有活性。
Synthesis, characterization, and tuning of the liquid crystal properties of ionic materials based on the cyclic polyoxothiometalate [{Mo<sub>4</sub>O<sub>4</sub>S<sub>4</sub>(H<sub>2</sub>O)<sub>3</sub>(OH)<sub>2</sub>}<sub>2</sub>(P<sub>8</sub>W<sub>48</sub>O<sub>184</sub>)]<sup>36−</sup>
A new class of cinnamate-based light-responsive ionic liquids was synthesized and characterized, and these ionic liquids with longer alkyl chains showed a remarkable increase in ionic conductivity under UV light irradiation in aqueous solutions.
Special Effect of Ionic Liquids on the Extraction of Flavonoid Glycosides from Chrysanthemum morifolium Ramat by Microwave Assistance
作者:Ying Zhou、Datong Wu、Pengfei Cai、Guifang Cheng、Chaobiao Huang、Yuanjiang Pan
DOI:10.3390/molecules20057683
日期:——
A microwave-assisted extraction approach based on ionic liquids of different chain lengths was successfully applied to the extraction of ten flavonoid glycosides from the flowering heads of Chrysanthemum morifolium Ramat. The pretreated sample was quantified by HPLC-ESI-MSn. The main components were identified as flavonoid glycosides, including three luteolin glycosides, three apigenin glycosides, three kaempferide glycosides, and one acacetin glycoside according to the characteristics of the corresponding CID mass spectrometric patterns. Eight ionic liquids from the imidazolium family with different chain lengths, namely, 1-alkyl-3-methylimidazolium bromide, [Cnmim]Br, (n = 2–16) were studied as extraction medium in water. Results indicated that alkyl chain length had an irregular impact on the extraction efficiency. Moreover, the best extraction efficiency was achieved by 1-dodecyl-3-methylimidazolium bromide aqueous solution ([C12mim]Br). Besides the alkyl chain length of the cations, other factors influencing extraction efficiency were systematically investigated, including concentration of the IL solutions, extraction time, matrix-to-solvent ratio and irradiation power.
thermodynamics of 1:1 inclusion complex formation between 1-alkyl-3-methylimidazolium type ionic liquids and cucurbit[7]uril was studied by isothermal titration calorimetry in aqueous solution at 298 K. The encapsulation proved to be enthalpy driven for all cations used. The enthalpy change upon binding (ΔH) became more negative when the 1-alkyl moiety of the imidazolium ring was gradually lengthened