聚合物支载过硼酸盐转化肟为羰基化合物的反应研究

过硼酸钠与强碱型离子交换树酯进行交换得到聚合物支载过硼酸盐氧化剂。该氧化剂与肟在醋酸中,于50-60℃反应2-3.5h,将肟转化为醛、酮,产率较高。     

聚合物支载氧化剂研究新进展

随着高分化学研究的深入,聚合物的应用范围越来越广。聚合物已用作催化剂、氧化剂、功能试剂等。本文综述自1989年以来聚合物支载氧化剂研究的新进展及在有机合成中的应用。     

聚合物支载三溴的氧化性能研究

本文利用聚合物支载三溴氧化伯醇及简单醚为酯，苯甲醇为苯甲醛，仲醇为酮，α.一二醇及环醚为内酯。该反应便于操作并有良好的产率。     

聚合物支载溴酸根的氧化性能研究

利用强碱型离子交换树脂支载溴酸根得到聚合物溴酸根氧化剂,它具有良好的氧化性能,在40%HBr或AlCl~3或NaHSO~3作用下,分别氧化伯醇和简单醚为酯,仲醇为酮,α、ω-二醇和环醚为内酯,硫(或硒)醇为二硫(或硒)化合物,并得到较好的产率。     

聚合物铬（VI）氧化剂的制备及其对醇的氧化研究

通过离子交换分别制得强碱，弱碱树脂负载的聚合物铬（ＶＩ）试剂，并研究了其对不同结构醇的氧化性能及反应条件。     

过硼酸钠在有机物选择性氧化反应中的应用

过硼酸钠(SPB) 作为一种安全、廉价、温和、多用途和对环境友好的氧化剂在有机合成中得到愈来愈广泛的应用。本文从不同官能团的选择性氧化和同一官能团的控制氧化两个方面综述它对一些有机物的选择性氧化反应。     

Aldehyde separation by polymer-supported oligo(ethyleneimines)

Chlorosulfonated styrene (10%) divinylbenzene resin beads reacted with an excess of ethylenediamine (EDA), diethylenetriamine (DETA), and triethylenetetramine (TETA) to give the corresponding sulfonamides with pendant oligo(ethyleneimines). The resulting modified resins are useful in the separation of aldehydes from hydrocarbon mixtures. Sorption of aldehydes occurs through formation of both Schiff base and five-membered (imidazoline) rings. Sorbed aldehydes can readily be stripped from the resins by treating with dilute acid solutions. Since the sulfamide bond has a reasonable stability toward acid-base hydrolysis, the loaded resins can be regenerated and recycled by simple acid-base washings, without losing their activity. In the present study, sorption and desorption kinetics of acetaldehyde, benzaldehyde, and salicylaldehyde have been investigated under different conditions. The aldehyde sorption obeys second-order kinetics. The method presented is applicable for all aromatic aldehydes. However, in the case of aliphatic aldehydes carrying an α-hydrogen, aldol condensation products form in solution. So aliphatic aldehydes and their aldol products are sorbed together by the resins. This limits the recovery of aliphatic aldehydes. Consequently, the resins described are cost effective sorbents for the removal and recovery of aromatic aldehydes from various mixtures. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2857–2864, 1997     

One-Pot Direct Oxidation of Primary Amines to Carboxylic Acids through Tandem ortho-Naphthoquinone-Catalyzed and TBHP-Promoted Oxidation Sequence

Biomimetic oxidation of primary amines to carboxylic acids has been developed where the copper-containing amine oxidase (CuAO)-like o-NQ-catalyzed aerobic oxidation was combined with the aldehyde dehydrogenase (ALDH)-like TBHP-mediated imine oxidation protocol. Notably, the current tandem oxidation strategy provides a new mechanistic insight into the imine intermediate and the seemingly simple TBHP-mediated oxidation pathways of imines. The developed metal-free amine oxidation protocol allows the use of molecular oxygen and TBHP, safe forms of oxidant that may appeal to the industrial application.     

Determination of trace trichlorfon by high performance liquid chromatography with UV detection based on its catalytic effect on sodium perborate oxidizing benzidine

Trichlorfon has the capacity to catalyze the oxidation of benzidine (4,4′-diamino-biphenyl) to 4-amino-4′-nitro biphenyl in the presence of sodium perborate. The product of the catalyzed reaction was validated by LC-MS method. Reversed-phase high performance liquid chromatography with 365 nm UV detection was used for separation and quantification of 4-amino-4′-nitro biphenyl. It can be proven there is a linear relationship between the peak areas of 4-amino-4′-nitro biphenyl and trichlorfon in the concentration range of 0.02-0.5 mg L⁻¹ (r = 0.9988). Limit of detection was 2.0 μg L⁻¹. A method for the indirect determination of trichlorfon using HPLC was developed based on catalytic effect of trichlorfon. Method validation was performed on samples spiked at three levels (0.5, 1.0, 1.5 mg kg⁻¹), the recoveries ranged from 67.5 to 82.1%, with relative standard deviations between 4.5 and 7.3%.0.01 mol L⁻¹ sodium dodecyl sulphate (SDS) solution was used to extract trichlorfon from samples and solid-phase extraction was used to isolate and concentrate trichlorfon in SDS solution. The recoveries of trichlorfon obtained with percolating the extraction through a SPE system were essentially in agreement with those obtained by liquid-liquid extraction. This new isolation technique decreases the use of toxic solvents and satisfies the requirements of Green Analytical Chemistry.     

Synthesis of polymer-supported phosphonium salts and their use as phase transfer catalysts

Spacer-modified polymer supports have been synthesized through the polymeric Grignard reagent method. Phosphonium-active sites were then introduced into these supports and the polymer-supported phosphonium salts were used as phase transfer catalysts for the nucleophilic substitution reactions. Influences of organic solvent, properties of the spacer and temperature on the catalytic activity have been investigated. Based on the experimental results, it was assumed that there might exist a dissolubility equilibrium of the catalytic site between the organic phase and the aqueous phase. With this idea, the results have been reasonably elucidated.     

过硼酸钠氧化硫醚生成砜

过硼酸钠是一种价廉易得的氧化剂,近来受到不少人的注意。为了探讨这种试剂能否用于使带有羟基、羰基、酯基、酰胺基和氰基的硫醚选择氧化生成相应的砜,我们合成了一系列硫醚(1_(a-m)),并研究了它们在冰醋酸中与过硼酸钠的反应。     

过硼酸钠在硫醚选择性氧化反应中的应用

过硼酸钠(NaBO_3·4H_2O)是一种可以使硫醚起选择性氧化反应生成相应亚砜的有效试剂,本文报道一系列苯硫醚化合物(1a-j)经氧化生成相应亚砜(2a-j),反应中烯键以及羟基、羰基、酯基、酰胺基、氰基等官能团未受影响。     

水／有机两相体系中杂多酸催化氧化芳香腈反应研究

考察了以杂多酸为催化剂,廉价、清洁、易得的氧气为氧化剂催化氧化腈生成酰胺的反应。实验结果表明,以氧气为氧化剂,杂多酸为催化剂的体系具有较高的活性和良好的选择性;磷钼酸较其它杂多酸有更佳的催化性能;底物芳环上带吸电子基时能加快反应速率,而腈基邻位基团的空间位阻引起反应速率下降。在优化的反应条件下,苯甲腈氧化反应的转化率和选择性分别达到了88%和99%,并且产品与催化剂易于分离,便于操作。     

选择性氧化含氰基的对硝基苯硫醚

选择性氧化含氰基的对硝基苯硫醚岳国仁，王建华，张正（南京大学化学系南京２１０００８）关键词含氰基硫醚，选择性氧化，四水合过硼酸钠据报道［１］对硝基苯磺酰基乙腈的合成，反应时间长，可采用四水合过硼酸钠（ＮａＢＯ３·４Ｈ２Ｏ）作为氧化剂，受到重视［２，３...