95-78-3Relevant articles and documents
Single-atom Fe-N4site for the hydrogenation of nitrobenzene: theoretical and experimental studies
Dong, Panpan,He, Rong,Liu, Yan,Lu, Ning,Mao, Junjie,Wu, Konglin,Zhang, Wenzhuang,Zheng, Yamin
supporting information, p. 7995 - 8001 (2021/06/21)
The hydrogenation of nitrobenzene to aniline is an important process in the industry of fine chemicals, but developing inexpensive catalysts with expected activity and selectivity still remains a challenge. By using density functional theory calculations, we demonstrated that the isolated Fe atom not only can weaken the adsorption of reactants and reaction intermediates as compared to Fe nanoparticles, but also remarkably decrease the reaction barrier for the hydrogenation of nitrobenzene to aniline. Thus, the Fe single-atom (Fe SA) catalyst is considered as an ideal catalyst for this reaction. This theoretical prediction has been subsequently confirmed by experimental results obtained for the Fe SAs loaded on N-doped hollow carbon spheres (Fe SAs/NHCSs) which achieved a conversion of 99% with a selectivity of 99% for the hydrogenation of nitrobenzene. The results significantly outperformed the Fe nanoparticles for this reaction. This work provides theoretical insight for the rational design of new catalytic systems with excellent catalytic properties.
Pyridyl Radical Cation for C?H Amination of Arenes
R?ssler, Simon L.,Jelier, Benson J.,Tripet, Pascal F.,Shemet, Andrej,Jeschke, Gunnar,Togni, Antonio,Carreira, Erick M.
, p. 526 - 531 (2019/01/04)
Electron-transfer photocatalysis provides access to the elusive and unprecedented N-pyridyl radical cation from selected N-substituted pyridinium reagents. The resulting C(sp2)?H functionalization of (hetero)arenes furnishes versatile intermediates for the development of valuable aminated aryl scaffolds. Mechanistic studies that include the first spectroscopic evidence of a spin-trapped N-pyridyl radical adduct implicate SET-triggered, pseudo-mesolytic cleavage of the N?X pyridinium reagents mediated by visible light.
Solvent-Driven Selectivity Control to Either Anilines or Dicyclohexylamines in Hydrogenation of Nitroarenes over a Bifunctional Pd/MIL-101 Catalyst
Chen, Xiaodong,Shen, Kui,Ding, Danni,Chen, Junying,Fan, Ting,Wu, Rongfang,Li, Yingwei
, p. 10641 - 10648 (2018/10/31)
The hydrogenation of nitroarenes is one of the most important strategies to produce the corresponding anilines and dicyclohexylamines, both of which are the fundamental raw materials in the synthesis of various pharmaceuticals and fine chemicals. Nevertheless, it is still a great challenge to develop a highly versatile and flexible catalytic system to selectively generate desired amines. Herein, we report the solvent-driven selectivity control over a bifunctional Pd/MIL-101 catalyst for the hydrogenation of nitrobenzene. An almost full selectivity of 99.9% to aniline or a surprising selectivity of 99.1% to dicyclohexylamine is achieved by using dimethylformamide (DMF, a polar solvent) or n-hexane (an apolar solvent) as the solvents, respectively. It is proposed that the polarity of solvents can effectively regulate the linkage between reactants/intermediates and Pd/MIL-101, affording controllable selectivities of aniline or dicyclohexylamine at will. In addition, the Lewis acid sites in Pd/MIL-101 can also effectively activate the aromatic ring and accelerate the cross-coupling reaction of amine. This solvent-driven catalytic system also exhibits good recyclability and compatibility for a wide substrate scope in both DMF and n-hexane, showing great promise for industrial applications. This study might open an avenue for the hydrogenation of nitroarenes to selectively produce anilines or dicyclohexylamines by simply regulating the solvent polarity over a bifunctional catalyst system.
