Zr(OH)₄‐Catalyzed Controllable Selective Oxidation of Anilines to Azoxybenzenes, Azobenzenes and Nitrosobenzenes

Abstract

The selective oxidation of aniline to metastable and valuable azoxybenzene,a zobenzene or nitrosobenzene has important practical significance in organic synthesis.However, uncontrollable selectivity and laborious synthesis of the expensive required catalysts severely hinders the uptake of these reactions in industrial settings.Herein, we have pioneered the discovery of Zr(OH) 4 as an efficient heterogeneous catalyst capable of the selective oxidation of aniline,u sing either peroxideo rO 2 as oxidant, to selectively obtain various azoxybenzenes,s ymmetric/unsymmetric azobenzenes,a sw ell as nitrosobenzenes,b ys imply regulating the reaction solvent, without the need for additives.M echanistic experiments and DFT calculations demonstrate that the activation of H 2 O 2 and O 2 is primarily achieved by the bridging hydroxyl and terminal hydroxyl groups of Zr(OH) 4 ,r espectively.T he present work provides an economical and environmentally friendly strategy for the selective oxidation of aniline in industrial applications.

Achieving High Photo/Thermocatalytic Product Selectivity and Conversion via Thorium Clusters with Switchable Functional Ligands

“…Because of the presence of competitive oxidation and condensation reactions in the catalytic oxidation of amines, it is difficult to control the selectivity of the oxidation products (AB, AOB, NSB, NB). − As a result, the oxidation of cheap and abundant aniline into high-value products is a challenge in the industry . To further explore the role of thorium clusters in the oxidation reaction, this model system was applied to the oxidation of aniline.…”

“…45−47 As a result, the oxidation of cheap and abundant aniline into high-value products is a challenge in the industry. 48 To further explore the role of thorium clusters in the oxidation reaction, this model system was applied to the oxidation of aniline. It is expected that the functionalized thorium cluster model system can selectively modulate the aniline oxidation products toward AOB, AB, NSB, and NB.…”

Dual-Function Detoxifying Nanofabrics against Nerve Agent and Blistering Agent Simulants

“…As shown in Figure a, the wide diffraction peak at around 17° from PAN fibers corresponds to the (100) plane, and the peak can also be observed in PAN@Zr­(OH) 4 . PAN@Zr­(OH) 4 shows another broad peak between 25 and 30°, demonstrating the amorphous structure of Zr­(OH) 4 . After solvothermal reaction, the characteristic diffraction peak of MOF-808 appeared in the XRD pattern of the sample.…”

Cerium-Doped Manganese Oxide Catalyst for the Oxidative Coupling Synthesis of Fluorescent 2-Amino-1,9-dimethyl-3H-phenoxazin-3-one Using Atmospheric Oxygen

“…23−25 Therefore, a cerium-doped manganese oxide may create a unique synergy between Mn and Ce, greatly enhancing their oxygen activation ability, realizing the replacement of H 2 O 2 with O 2 (or atmospheric oxygen) as the oxidant. 26 According to the research foundation of our group in aniline oxidation 27 and cerium doping, 28−30 herein, we report the development of a new cerium-doped manganese oxide catalyst, which possesses the appropriate oxidation and oxygen activation capacity for the oxidative coupling synthesis of substituted aminophenoxazinones, via the oxidative coupling of 2-aminophenols under an atmosphere of air.…”

“…According to the research foundation of our group in aniline oxidation and cerium doping, − herein, we report the development of a new cerium-doped manganese oxide catalyst, which possesses the appropriate oxidation and oxygen activation capacity for the oxidative coupling synthesis of substituted aminophenoxazinones, via the oxidative coupling of 2-aminophenols under an atmosphere of air.…”