Herein we report an effective and simple preparation method of substituted azoxybenzenes by reductive dimerization of nitrosobenzenes. This procedure requires no additional catalyst/reagent and can be applied to substrates with a wide range of substitution patterns.
Bismuth(III) chloride-zinc promoted selective reduction of aromatic nitro compounds to azoxy compounds
作者:Harsha N. Borah、Dipak Prajapati、Jagir S. Sandhu、Anil C. Ghosh
DOI:10.1016/s0040-4039(00)76858-4
日期:1994.5
In the presence of bismuth (III) chloride-metallic zinc aromaticnitrocompounds have been found to be selectively reduced inter and intramolecularly to the corresponding N-oxides at ambient temperature in high yields.
Cadmium Chloride-Zinc Catalysed Selective Reduction of Nitro Aromatics to Azoxy Compounds
作者:Bipul Baruah、Anima Boruah、Dipak Prajapati、Jagir S. Sandhu
DOI:10.1246/cl.1996.351
日期:1996.5
Treatment of aromaticnitrocompounds with cadmium chloride-metallic zinc combination systems has been shown to display a good reaction selectivity in the formation of symmetrical azoxycompounds in high yields.
用氯化镉-金属锌组合系统处理芳香硝基化合物已显示出在高产率形成对称偶氮化合物方面的良好反应选择性。
Unprecedented ortho-acylation of azoxybenzenes with α-oxocarboxylic acids by Pd-catalyzed C–H activation and decarboxylation
作者:Hongji Li、Pinhua Li、Qiong Zhao、Lei Wang
DOI:10.1039/c3cc45492d
日期:——
A palladium-catalyzed ortho-acylation reaction of azoxybenzenes with α-oxocarboxylic acids was developed in the presence of K2S2O8. The established methodology provides a direct approach to obtain acylated azoxybenzenes in good yields.
Niobium oxide prepared through a novel supercritical-CO<sub>2</sub>-assisted method as a highly active heterogeneous catalyst for the synthesis of azoxybenzene from aniline
作者:Yehan Tao、Bhawan Singh、Vanshika Jindal、Zhenchen Tang、Paolo P. Pescarmona
DOI:10.1039/c9gc02623a
日期:——
Nb2O5 nanoparticles were synthesised by a novel supercritical-CO2-assisted method (Nb2O5-scCO2) and were applied for the first time as a heterogeneouscatalyst in the oxidative coupling of aniline to azoxybenzene using the environmentally friendly H2O2 as the oxidant. The application of scCO2 in the Nb2O5-scCO2 resulted in significantly enhanced catalytic activity compared to a reference catalyst prepared
高表面积Nb2O5纳米颗粒是通过新型超临界CO2辅助方法(Nb2O5-scCO2)合成的,并首次以非均相催化剂的形式使用环境友好的H2O2作为氧化剂将苯胺氧化成a氧基苯。与没有scCO2(Nb2O5-Ref)或商业Nb2O5制备的参比催化剂相比,将scCO2应用于Nb2O5-scCO2可以显着提高催化活性。重要的是,Nb2O5-scCO2催化剂的苯胺转化率为86%(化学计量最大为93%,所用苯胺与H2O2的比例为1:1。4)乙氧基苯的选择性为92%,在45分钟内H2O2利用率为95%,而无需外部加热(反应是放热的),并且催化剂的负载极低(催化剂与底物的重量比,Rc / s = 0.005) 。该性能大大超过了先前报道的用于该反应的任何其他非均相催化剂的性能。另外,Nb2O5催化剂对取代的苯胺(例如甲基或乙基苯胺和对茴香胺)也显示出高活性,并在连续运行中重复使用而不会失去活性。通过N2-物理