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101.
Bo Xiao Ning-Ning Ji Xiao-Jie Cheng Chuan-Zeng Wang Jia-Jia Zhou 《Supramolecular chemistry》2013,25(1-2):4-12
Using the one-pot, direct strategy reported by Su and co-workers, we have synthesised a series of cucurbit[n]urils (Q[n], n = 5–8) and alkyl-substituted cucurbit[6]urils (SQ[6]s) anchored on polymers. Acrylamide, as a typical monomer, was used to synthesise a series of Q[n]s (n = 5–8) and SQ[6]-anchored polyacrylamides (PAMs) using a persulfate salt as initiator and oxidant. The Q[n]s (n = 5–8) and SQ[6]-anchored PAM samples have been characterised by 1H NMR, 1H NMR titrations of probe guests, Fourier-transform infrared and thermogravimetric analyser. The results confirmed that PAM chains had been successfully grafted on the back of the Q[n]s (n = 5–8) and SQ[6]s through an in situ radical polymerisation approach. It was further confirmed that the hydrophobic cavities of the Q[n]s on the polymers were still freely accessible. This synthetic approach may be extended to a variety of Q[n]s that are difficult to functionalise. 相似文献
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Hong-Kui Zhang Shou-Qiang Xu Jia-Jia Zhuang Jian-Liang Ye Pei-Qiang Huang 《Tetrahedron》2012,68(33):6656-6664
A flexible enantioselective approach to polyhydroxylated prolinol derivatives was described, which is based on the samarium diiodide-mediated reductive coupling of the chiral nitrone (3S,4R)-8, derived from d-isoascorbic acid with aldehydes/ketones. Thereby, polyhydroxyprolinol derivatives 9a–e and 9h–j were obtained from aromatic ketones and aliphatic aldehydes in good to excellent yields of 65–91%. These reductive hydroxyalkylations are highly diastereoselective in establishing the C-4 stereogenic center. By this way, the asymmetric syntheses of (?)-8a-epi-swainsonine (4) and (?)-8,8a-di-epi-swainsonine (5) have been achieved. 相似文献
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设计了一个可以将分析化学、无机化学、有机化学及物理化学集于一体的综合性实验。该实验首先可控合成具有三维孔道结构的ZSM-5分子筛,再运用X射线衍射、扫描电子显微镜及物理吸附对其结构、形貌和孔径分别进行表征;继而考察改变pH、吸附时间、吸附温度、ZSM-5使用量等因素对水中Cu2+吸附性能的影响。本实验涉及无机化学、有机化学中的合成理论知识,物理化学的表面吸附原理,分析化学中的数据处理方法及大型仪器的使用。在锻炼了学生动手操作能力的基础上,又提高了学生对实验结果进行分析、评价的综合能力。 相似文献
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通过水热的方法合成出了六角星形的Cu2O微米晶,这一六角星形貌是腐蚀八面体的六个{111}面形成的,我们讨论了反应中的各个实验条件对产物形貌和成分的影响,发现浓度对产物的形貌有重要的影响,只有反应物的浓度低于一定的值时,才会形成八面体,随着反应物浓度的增加,产物的形貌会由八面体逐渐转变成了球形;氨水对产物的形貌有一定的影响,柠檬酸钠在反应中既是还原剂,又作为表面活性剂对产物的形貌有重要的影响,对形成六角星形Cu2O过程中对八面体表面的腐蚀是氨水和柠檬酸钠共同的作用。 相似文献
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在阳极铝膜腔体内, 以三嵌段聚合物F127为表面活性剂合成出一维纳米介孔二氧化硅材料. 采用压力诱导合成方法能使纳米纤维沿着铝膜腔体有序生长排列, 并且只存在于铝膜的腔体内, 在铝膜表面没有残留. 在纳米纤维的两侧可以清楚地观察到具有六边形结构的孔道, 直径为12 nm. 考察了正硅酸乙酯的水解时间以及化合物的不同配比对材料形貌的影响. 相似文献
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A new square-planar platinum(Ⅱ) complex, [Pt(Me3SiC≡Cphen)(C≡CC6H4Cl-3)2](1), was synthesized by using 3-trimethylsilylethynyl-1,10-phenanthroline(Me3SiC≡Cphen) and 3-chlorophenylacetylene ligands, and its structure was characterized by single-crystal X-ray crystallography. 1 crystallizes in triclinic, space group P1 with a = 6.9524(5), b = 12.7796(11), c = 17.5846(10) ?, α = 78.484(5), β = 88.700(5), γ = 75.600(6)°, V = 1482.23(19) ?3, Z = 2, C33H24Cl2N2 PtSi, Mr = 742.62, Dc = 1.664 g/cm3, F(000) = 724, μ(Mo Ka) = 4.979 mm-1, R = 0.0369 and wR = 0.0786. In 1, adjacent molecules along the a axis are stacked in a columnar structure through π···π interactions, and such neighboring columnar structures are connected with each other by C–H···π hydrogen bonds to form a 2D supramolecular network. 1 exhibits reversible luminescence mechanochromic property with the luminescence red shift in a range of ca. 146~182 nm. Extremely large red-shifts of luminescence spectra suggest that luminescent mechanochromic property of 1 is due to the formation of aggregate via Pt–Pt interaction during the mechanical grinding. Based on this property, a simple device was developed and used for rewritable data storage. 相似文献
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In this work, the ionic solvation and association behaviours in the LiCl aqueous solution were investigated using density functional theory (DFT), a polarised continuum model and classical molecular dynamics simulations. DFT calculations of LiCl(H2O)1–6,8 clusters show that contact ion pair (CIP) and solvent-shared ion pair (SSIP) conformers of LiCl(H2O)n (n ≥ 4) clusters are generally energetic both in the gas phase and in the aqueous solution. Some SSIP conformers may be slightly more stable than their CIP isomers when at least eight water molecules are incorporated in the inner hydration shells of LiCl hydrates. The transformation between CIP and SSIP conformers is easy by overcoming a small energy barrier, which mainly results from the hydration shell reorganisation of Li+. Molecular dynamics simulations show that ion pairs or ion clusters can be found in the LiCl aqueous solution, and the probability of CIP conformers or ion clusters presented in the LiCl solution generally increases with rise in temperature. However, the presentation of ion pairs or ion clusters in the LiCl aqueous solution does not inevitably lead to the nucleation of LiCl crystallisation. 相似文献