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11.
Air oxidation of N-cyclopropylanilines was shown to occur under either ambient conditions or accelerated conditions (warming or shining light) in an open container. A subsequent fragmentation resulted in formation of the corresponding acetamide. While potential mechanisms have been previously proposed, simple aerobic oxidation to β-hydroxy-propionamides in the absence of a radical promoter has not been previously reported. 相似文献
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Qiaoxia Guo Wennian Wang Weiling Teng Liwei Chen Yanqing Wang Baojian Shen 《合成通讯》2013,43(17):2574-2584
A convenient one-pot method for the synthesis of substituted quinolines via the reaction of aniline and aldehyde in the presence of a Lewis acid (AlCl3) and an oxidant (H2O2) has been developed. Hydrogen peroxide was found to promote the reaction by its function as a hydrogen hunter, hindering the formation of by-product N-alkylaniline. The effect of the oxidant on the yield and selectivity was studied. When the molar ratio of aniline, n-butyraldehyde, and H2O2 was 1:3:0.5 at 25 °C, the yield of 3-ethyl-2-propylquinoline was improved from 64% (reaction without H2O2) to 84% (with H2O2), and the quinoline selectivity was improved to almost 100%. Moreover, the reaction time was obviously reduced. The substituent effect was also investigated in this work. 相似文献
13.
Jasmin Shah M. Rasul Jan Behisht Ara 《International journal of environmental analytical chemistry》2013,93(15):1077-1085
A simple sensitive spectrophotometric method has been developed for the determination of atrazine in herbicide formulations and real samples. The method was based on the reaction of atrazine with pyridine to form a quaternary halide which in the presence of alkali forms a carbinol base. The heterocyclic ring of the carbinol base breaks and forms the glutaconic dialdehyde. The glutaconic dialdehyde group was coupled with sulfanilic acid to form a yellow coloured product having λ max 450 nm or coupled with aniline to form a orange red coloured product having λ max 480 nm. The Beer's law was obeyed over the range from 0.1 to 25 µg mL?1 and molar absorptivity 1.5 × 104 L mol?1 cm?1 for sulfanilic acid, and from 0.08 to 12 µg mL?1 and molar absorptivity 1.3 × 104 L mol?1 cm?1 for aniline were observed. The reaction conditions and other analytical parameters were optimised. The proposed method has been successfully applied for the analysis of commercial formulations and real samples. 相似文献
14.
The 2H NMR of uniaxially strained swollen chloroprene rubbers and butadiene-styrene copolymers with different crosslink densities is studied. the relative number of chain segments between cross-links of various samples is obtained. the results are in approximate agreement with those obtained from the Flory equilibrium-swelling method. It is found that the enhancement factor G depends not only on the lattice-walk model and swelling of rubber, such as Tanaka etc. expected, but also on the crosslink density and the structure of the rubber. the formula relating G to the number of chain segments between cross links is derived from theory. Moreover, we can also estimate the relation between the enhancement factor Gr of real rubber and G calculated from the theory of the lattice model. the 2H NMR results of these samples indicate that the interaction between chain segments decreases with increasing crosslink density. 相似文献
15.
Yonglan Luo 《Supramolecular chemistry》2013,25(8):765-768
In this communication, I report the formation of novel supramolecular one-dimensional (1D) structures including microbelts and microprisms by a direct mix of aniline and H2PdCl4 aqueous solutions at room temperature. As-formed supramolecular structures were characterised by scanning electron microscopy, X-ray photoelectron spectra and X-ray diffraction techniques. Both coordination and π–π interactions are expected to be responsible for these 1D microstructures. It suggests that the molar ratio of the reactants is crucial to the formation of such 1D structures. 相似文献
16.
《Green Chemistry Letters and Reviews》2013,6(3):403-407
Abstract The synthesis of diamino triphenyl methanes from aniline and aromatic aldehydes was conducted in near critical water and supercritical water. The reaction parameters, such as temperature, density, and reaction time, have been studied. Significant acceleration of the condensation reaction of aniline and aromatic aldehydes can be achieved by using high temperature water, especially near the critical point, in the absence of any acid catalysts. It has been demonstrated that high temperature water act effectively in the place of conventional acid catalysts. 相似文献
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在硒催化下,苯胺和硫醇在一氧化碳和氧气作用下发生氧化羰基化反应直接生成相应的硫代氨基甲酸酯,收率从中等到良好. 反应在室温无溶剂条件下进行. 催化剂硒能方便地回收且能循环使用. 相似文献
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