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761.
Ruihang Jiang Zhangpei Chen Kun Zhan Lei Liu Junjie Zhou Yongjian Ai Shuang Li Hongjie Bao Zenan Hu Li Qi Jingting Wang Hong-bin Sun 《Tetrahedron letters》2018,59(34):3279-3282
The vinyl benzoate derivatives were successfully synthesized by the transvinylation reactions that vinyl group transferred from vinyl acetate to aromatic carboxylic acids with the recoverable catalyst RhCl3·3H2O. This catalyst features air stable and tolerance of water, good reusable ability, meanwhile, shows high selectivity for aromatic carboxylic acid in the presence of phenolic hydroxyl. With this method, a variety of vinyl benzoate derivatives can be produced with up to 95% yield. 相似文献
762.
《高分子科学杂志,A辑:纯化学与应用化学》2013,50(11):1227-1240
Abstract Semi‐ and full‐interpenetrating polymer networks (IPNs) of uralkyd (UA) resin based on hydrogenated castor oil and poly(butyl acrylate) (PBA) were prepared by the sequential mode of synthesis. These IPNs were characterized for their resistance to thermal behavior, swelling (%), and mechanical properties. The morphology of the IPNs was studied by scanning electron microscopy (SEM). The effect of the variations of the blend ratios on the above‐mentioned properties was examined. The mechanical properties significantly enhanced by increasing UA component in the blend. Full‐IPNs exhibited higher apparent densities, mechanical properties, and thermal stability than the corresponding semi‐IPNs. 相似文献
763.
阐明生物内各种相关活性物质及其实时变化、生理分布与生物功能是探索自身与生命奥秘的重要组成部分。化学荧光探针是该领域研究的重要工具之一。含磷荧光探针因具有较强的还原性、良好的水溶性与生物相容性,可利用其特异性化学反应或者物理作用检测细胞内各种特定的分析底物。近几年基于不同含磷官能团荧光探针的研究取得了较大进展,本文对相关研究进行了梳理,对含磷官能团类的荧光探针进行归纳总结:主要包括2-(二苯基磷)苯甲酸酯类、磷酸酯类、二苯基磷酰类和三苯基磷阳离子等类型荧光探针,为进一步探索构建新的含磷基团荧光探针提供借鉴与参考。 相似文献
764.
765.
The kinetics is studied for the phase transfer catalytic preparation of benzyl benzoate from sodium benzoate and benzyl chloride with tetrabutylaramonium iodide as catalyst in a well stirred batch reactor. Benzyl chloride is dissolved in toluene as the organic phase and sodium benzoate is dissolved in water as the aqueous phase. The kinetics of the overall reaction is described by a first-order model based on the concentration of benzyl chloride in the organic phase at the later time of the batch reaction. The rate constant increases with an increase of the catalyst concentration while decreases slightly with an increase of the concentration of sodium benzoate under the experimental condition. 相似文献
766.
高效液相色谱荧光检测法测定蔬菜中残留的甲氨基阿维菌素苯甲酸盐 总被引:2,自引:0,他引:2
建立了甘蓝和蘑菇中甲氨基阿维菌素苯甲酸盐的固相萃取-高效液相色谱荧光分析方法。蔬菜样品用乙酸乙酯提取,提取液旋转浓缩近干后用少量乙酸乙酯溶解,再经PRS固相萃取(SPE)柱净化,洗脱液经氮气吹干后用氮甲基咪唑和三氟乙酸酐衍生,衍生物用高效液相色谱分析,采用外标法定量。在添加浓度1.0~20.0 μg/kg范围内,平均添加回收率为78.6%~84.9%,日内相对标准偏差(RSD)为2.7%~6.0%,日间RSD为3.1%~8.9%,检出限为0.10 μg/kg。甲氨基阿维菌素苯甲酸盐衍生物在0.002~0.10 mg/L范围内呈良好的线性关系,相关系数为0.9999。 相似文献
767.
三烃基(Ph,Cy,Bu)锡芳硫(亚砜,砜)乙酸酯的合成及表征 总被引:3,自引:0,他引:3
合成了22种三烃基(Ph,Cy,Bu)锡芳硫(亚砜,砚)乙酸酯,用元素分析、IR、HNMR、MS、XPS等手段对其结构进行了表征,结果表明,三环己基锡芳硫(亚砜、砜)乙酸酯具有四配位锡原子的单体结构,三苯基(三丁基)锡芳硫(亚砜、砜)乙酸醌具有五配位原子的聚合结构,通过估算它们的正辛醇-水分配系数,预测其在环境中的吸附及生物富集能力。 相似文献
768.
André Grüßing Sven Rau Sebastian Schebesta Alexander Scholz Helmar Görls Dirk Walther Prof. Dr. 《无机化学与普通化学杂志》2007,633(7):961-970
Syntheses and Structures of Bis(4,4′‐t‐butyl‐2,2′‐bipyridine) Ruthenium(II) Complexes with functional Derivatives of Tetramethyl‐bibenzimidazole [(tbbpy)2RuCl2] reacts with dinitro‐tetramethylbibenzimidazole ( A ) in DMF to form the complex [(tbbpy)2Ru( A )](PF6)2 ( 1a ) (tbbpy: bis(4,4′‐t‐butyl)‐2,2′bipyridine). Exchange of the two PF6? anions by a mixture of tetrafluor‐terephthalat/tetrafluor‐terephthalic acid results in the formation of 1b in which an extended hydrogen‐bonded network is formed. According to the 1H NMR spectra and X‐ray analyses of both 1a and 1b , the two nitro groups of the bibenzimidazole ligand are situated at the periphery of the complex in cis position to each other. Reduction of the nitro groups in 1a with SnCl2/HCl results in the corresponding diamino complex 2 which is a useful starting product for further functionalization reactions. Substitution of the two amino groups in 2 by bromide or iodide via Sandmeyer reaction results in the crystalline complexes [(tbbpy)2Ru( C )](PF6)2 and [(tbbpy)2Ru( D )](PF6)2 ( C : dibromo‐tetrabibenzimidazole, D : diiodo‐tetrabibenzimidazole). Furthermore, 2 readily reacts with 4‐t‐butyl‐salicylaldehyde or pyridine‐2‐carbaldehyde under formation of the corresponding Schiff base RuII complexes 5 and 6 . 1H NMR spectra show that the substituents (NH2, Br, I, azomethines) in 2 ‐ 6 are also situated in peripheral positions, cis to each other. The solid state structure of both 2 , and 3 , determined by X‐ray analyses confirm this structure. In addition, the X‐ray diffraction analyses of single crystals of the complexes [(tri‐t‐butyl‐terpy)(Cl)Ru( A )] ( 7 ) and [( A )PtCl2] ( 8 ) display also that the nitro groups in these complexes are in a cis‐arrangement. 相似文献
769.
合成了三种亲疏水性不同的温度及pH敏感的PAAc/P(NIPAAm-co-BMA)、PAAc/PNIPAAm和PAAc/P(NIPAAm-co-AAm)互穿网络(IPN)水凝胶,以水杨酸钠和水杨酸为模型药物,研究了温度、pH值及药物和凝胶的亲疏水性相互作用对模型药物释药性能的影响。研究结果表明,随着凝胶亲水性的增强,水杨酸钠的载药率提高,释药率也越大;相反疏水性增强也有利于提高水杨酸的载药率;IPN凝胶在水中的释药过程属于溶胀支配型释放,药物释放率随凝胶的亲水性增强而增强,同时,载药凝胶在45℃水中的释药率大于25℃时的释药率。在25℃时,水杨酸在pH=2.2的缓冲溶液中几乎不释放,而在pH=7.4的缓冲溶液中能以较快的速率释放。 相似文献
770.