The polyhedral nature of selenium-catalysed reactions: Se(<scp>iv</scp>) species instead of Se(<scp>vi</scp>) species make the difference in the on water selenium-mediated oxidation of arylamines
Selenium-catalysed oxidations are highly sought after in organic synthesis and biology. Herein, we report our studies on the on water selenium mediated oxidation of anilines. In the presence of diphenyldiselenide or benzeneseleninic acid, anilines react with hydrogen peroxide, providing direct and selective access to nitroarenes. On the other hand, the use of selenium dioxide or sodium selenite leads
硒催化氧化在有机合成和生物学中备受追捧。在此,我们报告了我们对水硒介导的苯胺氧化的研究。在二苯基二硒化物或苯硒酸存在下,苯胺与过氧化氢反应,直接和选择性地获得硝基芳烃。另一方面,使用二氧化硒或亚硒酸钠会产生氧化偶氮芳烃。仔细的机理分析和77 Se NMR 研究表明,只有 Se( IV ) 物质,如苯过氧硒酸,是参与在水中运行并导致硝基芳烃的催化循环的活性氧化剂。虽然最近在有机溶剂中发生的其他硒催化氧化反应已被证明是通过 Se( VI) 关键中间体,苯胺在水中氧化成硝基芳烃没有。这些发现揭示了有机硒催化转化的多方面性质,并开辟了利用硒基催化的新方向。
SO2F2-mediated oxidation of primary and tertiary amines with 30% aqueous H2O2 solution
作者:Xudong Liao、Yi Zhou、Chengmei Ai、Cuijiao Ye、Guanghui Chen、Zhaohua Yan、Sen Lin
DOI:10.1016/j.tetlet.2021.153457
日期:2021.11
highly efficient and selective oxidation of primary and tertiaryamines employing SO2F2/H2O2/base system was described. Anilines were converted to the corresponding azoxybenzenes, while primary benzylamines were transformed into nitriles and secondary benzylamines were rearranged to amides. For tertiaryamine substrates quinolines, isoquinolines and pyridines, their oxidation products were the corresponding
描述了使用 SO 2 F 2 /H 2 O 2 /碱系统对伯胺和叔胺进行高效和选择性氧化。苯胺转化为相应的偶氮苯,而伯苄胺转化为腈,仲苄胺重排为酰胺。对于叔胺底物喹啉、异喹啉和吡啶,它们的氧化产物是相应的N-氧化物。反应条件非常温和,仅涉及 SO 2 F 2、胺类、30% H 2 O 2水溶液溶液和无机碱在室温下。一个独特的优点是该氧化系统仅由廉价的无机化合物组成,而没有使用任何金属和有机化合物。
Modulating the catalytic behavior of non-noble metal nanoparticles by inter-particle interaction for chemoselective hydrogenation of nitroarenes into corresponding azoxy or azo compounds
作者:Lichen Liu、Patricia Concepción、Avelino Corma
DOI:10.1016/j.jcat.2018.11.011
日期:2019.1
Aromatic azoxy compounds have wide applications and they can be prepared by stoichiometric or catalytic reactions with H2O2 or N2H4 starting from anilines or nitroarenes. In this work, we will present the direct chemoselective hydrogenation of nitroarenes with H2 to give aromatic azoxy compounds under base-free mild conditions, with a bifunctional catalytic system formed by Ni nanoparticles covered
芳族乙氧基化合物具有广泛的用途,它们可以通过化学计量或催化反应与H 2 O 2或N 2 H 4从苯胺或硝基芳烃开始反应制备。在这项工作中,我们将介绍在无碱温和条件下用H 2直接对硝基芳烃进行化学选择性加氢以生成芳族氮氧基化合物的方法,该方法是由覆盖有几层碳的Ni纳米颗粒形成的双功能催化体系([受电子邮件保护] NPs )和CeO 2纳米粒子。[受电子邮件保护的] 2催化剂的催化性能超过了最新的Au / CeO 2由硝基苯直接生产production氧基苯的催化剂。借助动力学和光谱学结果,提出了一种双功能机理,其中硝基苯的氢化可以在转化率> 95%和选择性> 93%的情况下终止于乙氧基苯的生成,或者可以进一步推动硝基苯的氢化以形成偶氮苯。 > 85%的选择性。通过用非贵金属制备双官能催化剂,不仅可以实现硝基芳烃的化学选择性加氢成苯胺,而且还可以实现相应的氮氧基和偶氮化合物的化学选择性加氢。
Studies on organic fluorine compounds. XVII. Reaction of benzotrifluoride derivatives with sodium amide.
Reaction of benzotrifluoride derivatives with sodium amide was examined. o-Nitro-and p-amino-benzotrifluoride gave the corresponding benzonitriles. m-Nitrobenzotrifluoride gave 3, 3'-bis (trifluoromethyl) azoxybenzene and 3, 8-bis (trifluoromethyl) benzo [c]-cinnoline 5-oxide. p-Nitrobenzotrifluoride gave p-nitrobenzonitrile, 2, 2'-dinitro-5, 5'-bis (trifluoromethyl) biphenyl and 4, 4'-dicyanoazoxybenzene. Reaction mechanism for each product is proposed.
A new non-metal heterogeneous catalyst for the activation of hydrogen peroxide: a perfluorinated ketone attached to silica for oxidation of aromatic amines and alkenes
作者:Karine Neimann、Ronny Neumann
DOI:10.1039/b100421m
日期:——
A silane functionalized by octafluoroacetophenone was
polymerized by the sol–gel method to form an insoluble silicate with
perfluoroketone pendants; the silicate was used as a heterogeneous catalyst
for the activation of aqueous hydrogen peroxide and the oxidation of
aromatic amines and alkenes.