12221-03-3Relevant academic research and scientific papers
Bio-inspired noble metal-free reduction of nitroarenes using NiS2+x/g-C3N4
Zhang, Ya-Nan,Li, Xin-Hao,Cai, Yi-Yu,Gong, Ling-Hong,Wang, Kai-Xue,Chen, Jie-Sheng
, p. 60873 - 60877 (2014)
We introduce the concept of bio-inspired catalytic hydrogenation of nitroarenes by mimicking the catalytic behavior of enzymes with NiS2+x nanoparticles and polymeric melon (g-C3N4). The g-C3N4-supported NiS2+x nanoparticles functioned as ligand-free and noble metal-free catalysts and offered high efficiency, comparable to noble metal-based catalysts, but at a much better selectivity.
Palladium Immobilized on a Polyimide Covalent Organic Framework: An Efficient and Recyclable Heterogeneous Catalyst for the Suzuki–Miyaura Coupling Reaction and Nitroarene Reduction in Water
Dong, Zhenhua,Pan, Hongguo,Gao, Pengwei,Xiao, Yongmei,Fan, Lulu,Chen, Jing,Wang, Wentao
, p. 299 - 306 (2021/05/10)
An efficient and recyclable Pd nano-catalyst was developed via immobilization of Pd nanoparticles on polyimide linked covalent organic frameworks (PCOFs) that was facilely prepared through condensation of melamine and 3,3′,4,4′-biphenyltetracarboxylic dianhydride. The Pd nanoparticles (Pd NPs) catalyst was thoroughly characterized by FT-IR, XRD, SEM, TEM. Furthermore, the catalytic activity of Pd NPs catalyst was evaluated by Suzuki–Miyaura coupling reaction and nitroarene reduction in water, respectively. The excellent yields of corresponding products revealing revealed that the Pd NPs catalyst could be applied as an efficient and reusable heterogeneous catalyst for above two reactions. Graphical Abstract: [Figure not available: see fulltext.]
Catalytic Deoxygenation of Nitroarenes Mediated by High-Valent Molybdenum(VI)-NHC Complexes
Liu, Shenyu,Amaro-Estrada, Jorge Ivan,Baltrun, Marc,Douair, Iskander,Schoch, Roland,Maron, Laurent,Hohloch, Stephan
supporting information, p. 107 - 118 (2021/02/05)
The high-valent molybdenum(VI) N-heterocyclic carbene complexes, (NHC)MoO2 (1) and (NHC)MoO(NtBu) (2) (NHC = 1,3-bis(3,5-di-tert-butyl-2-phenolato)-benzimidazol-2-ylidene), are investigated toward their catalytic potential in the deoxygenation of nitroarenes. Using pinacol as the sacrificial and green reductant, both complexes are shown to be very active (pre)catalysts for this transformation allowing a reduction of the catalyst loading down to 0.25 mol %. Mechanistic investigations show μ-oxo bridged molybdenum(V) complexes [(NHC)MoO]2O (4) and [(NHC)Mo(NtBu)]2O (5) as well as zwitterionic pinacolate benzimidazolium complex 6, with a doubly protonated NHC ligand, to be potentially active species in the catalytic cycle. Both 4 and 5 can be prepared independently by the deoxygenation of 1 and 2 using triethyl phosphine (PEt3) or triphenyl phosphine (PPh3) and were shown to exhibit an unusual multireferenced ground state with a very small singlet-triplet gap at room temperature. Computational studies show that the spin state plays an unneglectable role in the catalytic process, efficiently lowering the reaction barrier of the deoxygenation step. Mechanistic details, putting special emphasis on the fate of the catalyst will be presented and potential routes how nitroarene reduction is facilitated are evaluated.
Rhodium nanoparticles supported on 2-(aminomethyl)phenols-modified Fe3O4 spheres as a magnetically recoverable catalyst for reduction of nitroarenes and the degradation of dyes in water
Chen, Tian,Chen, Zhangpei,Hu, Jianshe,Lv, Kexin,Reheman, Aikebaier,Wang, Gongshu
, (2021/06/18)
A magnetic nanostructured catalyst (Fe3O4@SiO2-Amp-Rh) modified with 2-(aminomethyl)phenols (Amp) was designed and prepared, which is used to catalyze the reduction of aromatic nitro compounds into corresponding amines and the degradation of dyes. The 2-aminomethylphenol motif plays a vital role in the immobilization of rhodium nanoparticles to offer extraordinary stability, which has been characterized by using various techniques, including transmission electron microscopy (TEM), thermal gravimetric analyzer (TGA), X-Ray Diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). A variety of nitroaromatic derivatives have been reduced to the corresponding anilines in water with up to yields of 99% within 1?h at room temperature. In addition, the catalyst system is effective in catalyzing the reduction of toxic pollutant 4-nitrophenol and the degradation of MO, MB and RhB dyes. Importantly, this catalyst Fe3O4@SiO2-Amp-Rh can be easily recovered by an external magnetic field because of the presence of magnetic core of Fe3O4, and the activity of Fe3O4@SiO2-Amp-Rh does not decrease significantly after 7 times’ recycling, which indicates that the catalyst performed high reactivity as well as stability. Graphical abstract: [Figure not available: see fulltext.]
Synthesis and characterization of chitosan pyridyl imine palladium (CPIP) complex as green catalyst for organic transformations
Chundawat, Narendra Singh,Pathan, Sultan,Singh, Girdhar Pal,Deuri, Arup Saha,Zarrintaj, Payam,Chauhan, Narendra Pal Singh
, p. 2835 - 2850 (2021/02/11)
In this work, the modification of chitosan using 2-acetyl pyridine has been used to prepare an intermediate, chitosan pyridyl imine (CPI), in first step and then in second step it is further reacted with Pd(OAc)2 to develop chitosan pyridyl imine palladium (CPIP) complex catalyst in a very simplistic way. The formed CPIP has been extensively characterized with respect to raw chitosan utilizing methods including FT-IR, pyrolysis GC–MS, XRD, XPS, FE-SEM, EDS, TGA-DTG and DSC. TG-DSC study suggested that the catalyst is thermally stable up to 300?°C. This catalyst shows an excellent activity in the reduction of toxic pollutant nitrobenzene to less toxic aniline. CPIP complex has also been found to give magnificent results in Suzuki–Miyaura and Heck cross-coupling reactions, and therefore, using this green catalyst, the toxic phosphine ligand can be excluded from cross-coupling reactions. This study furnishes an economic and eco-friendly catalyst for organic transformation in sustainable chemistry.
Magnetically‐recoverable Schiff base complex of Pd(II) immobilized on Fe3O4@SiO2 nanoparticles: an efficient catalyst for the reduction of aromatic nitro compounds to aniline derivatives
Azadi, Sedigheh,Esmaeilpour, Mohsen,Sardarian, Ali Reza
, p. 809 - 821 (2021/07/20)
Fe3O4@SiO2/Schiff base/Pd(II) is reported as a magnetically recoverable heterogeneous catalyst for the chemoselective reduction of aromatic nitro compounds to the corresponding amines through catalytic transfer hydrogenation (CTH). In this regard, a small amount of the nanocatalyst (0.52?mol% Pd) and hydrazine hydrate, showing safe characteristics and perfect ability as the hydrogen donor, were added to the nitro substrates. The experiments described the successful reduction of aromatic nitro compounds with good to excellent yields and short reaction times. The catalyst, due to its magnetic property, could be simply separated from the reaction mixture by a permanent magnet and reused in seven consecutive reactions without considerable loss in its activity. Moreover, the leaching of Pd was only 3.6% after the seventh run. Thus, the most striking feature of this method is to use a small amount of the magnetic nanocatalyst along with a cheap and safe hydrogen source to produce the important amine substances selectively, which makes the method economical, cheap, environmentally friendly, and simple. Graphic abstract: [Figure not available: see fulltext.]
Highly porous copper-supported magnetic nanocatalysts: made of volcanic pumice textured by cellulose and applied for the reduction of nitrobenzene derivatives
Fazeli, Atefeh,Maleki, Ali,Qazi, Fateme Sadat,Saeidirad, Mahdi,Shalan, Ahmed Esmail,Taheri-Ledari, Reza
, p. 25284 - 25295 (2021/08/05)
Herein, a novel designed heterogeneous catalytic system constructed of volcanic pumice magnetic particles (VPMPs), cellulose (CLS) as a natural polymeric matrix, and copper nanoparticles (Cu NPs) is presented. Also, to enhance the inherent magnetic property of VPMP, iron oxide (Fe3O4) nanoparticles have been prepared and incorporated in the structureviaanin situprocess. As its first and foremost excellent property, the designed composite is in great accordance with green chemistry principles because it contains natural ingredients. Another brilliant point in the architecture of the designed composite is the noticeable porosity of VPMP as the core of the composite structure (surface area: 84.473 m2g?1). This great porosity leads to the use of a small amount (0.05 g) of the particles for catalytic purposes. However, the main characterization methods, such as Fourier-transform infrared and energy-dispersive X-ray spectroscopy, thermogravimetric analysis, and electron microscopy, revealed that the spherical metallic particles (Fe and Cu oxides) were successfully distributed onto the surface of the VPMP and CLS matrices. Further, vibrating-sample magnetometer analysis confirmed the enhancement of the magnetic property (1.5 emu g?1) of the composite through the addition of Fe3O4nanoparticles. Further, the prepared (Fe3O4@VPMP/CLS-Cu) nanocomposite has been applied to facilitate the reduction reaction of hazardous nitrobenzene derivatives (NBDs) to their aniline analogs, with 98% conversion efficiency in eight minutes under mild conditions. Moreover, the good reusability of the catalytic system has been verified after recycling it ten times without any significant decrease in the performance.
Highly efficient hydrogenation reduction of aromatic nitro compounds using MOF derivative Co-N/C catalyst
Dai, Yuyu,Li, Xiaoqing,Wang, Likai,Xu, Xiangsheng
, p. 22908 - 22914 (2021/12/24)
The direct hydrogenation reduction of aromatic nitro compounds to aromatic amines with non-noble metals is an attractive area. Herein, the pyrolysis of Co(2-methylimidazole)2 metal-organic framework successfully produces a magnetic Co-N/C nanocomposite, which exhibits a porous structure with a high specific area and uniform Co nanoparticle distribution in nitrogen-doped graphite. In addition, the Co-N/C catalysts possess high cobalt content (23%) with highly active β-Co as the main existing form and high nitrogen content (3%). These interesting characteristics endow the Co-N/C nanocomposite with excellent catalytic activity for the hydrogenation reduction of nitro compounds under mild conditions. In addition, the obtained Co-N/C nanocomposites possess a broad substrate scope and good cycle stability for the reduction of halogen-substituted or carbonyl substituted phenyl nitrates. This journal is
Selective Reduction of Nitroarenes to Arylamines by the Cooperative Action of Methylhydrazine and a Tris(N-heterocyclic thioamidate) Cobalt(III) Complex
Ioannou, Dimitris I.,Gioftsidou, Dimitra K.,Tsina, Vasiliki E.,Kallitsakis, Michael G.,Hatzidimitriou, Antonios G.,Terzidis, Michael A.,Angaridis, Panagiotis A.,Lykakis, Ioannis N.
supporting information, p. 2895 - 2906 (2021/02/27)
We report an efficient catalytic protocol that chemoselectively reduces nitroarenes to arylamines, by using methylhydrazine as a reducing agent in combination with the easily synthesized and robust catalyst tris(N-heterocyclic thioamidate) Co(III) complex [Co(κS,N-tfmp2S)3], tfmp2S = 4-(trifluoromethyl)-pyrimidine-2-thiolate. A series of arylamines and heterocyclic amines were formed in excellent yields and chemoselectivity. High conversion yields of nitroarenes into the corresponding amines were observed by using polar protic solvents, such as MeOH and iPrOH. Among several hydrogen donors that were examined, methylhydrazine demonstrated the best performance. Preliminary mechanistic investigations, supported by UV-vis and NMR spectroscopy, cyclic voltammetry, and high-resolution mass spectrometry, suggest a cooperative action of methylhydrazine and [Co(κS,N-tfmp2S)3] via a coordination activation pathway that leads to the formation of a reduced cobalt species, responsible for the catalytic transformation. In general, the corresponding N-arylhydroxylamines were identified as the sole intermediates. Nevertheless, the corresponding nitrosoarenes can also be formed as intermediates, which, however, are rapidly transformed into the desired arylamines in the presence of methylhydrazine through a noncatalytic path. On the basis of the observed high chemoselectivity and yields, and the fast and clean reaction processes, the present catalytic system [Co(κS,N-tfmp2S)3]/MeNHNH2 shows promise for the efficient synthesis of aromatic amines that could find various industrial applications.
Generation of a Sulfinamide Species from Facile N-O Bond Cleavage of Nitrosobenzene by a Thiolate-Bridged Diiron Complex
Chen, Yifeng,Qu, Jingping,Wang, Baomin,Xu, Sunlin,Yang, Dawei,Ye, Shengfa
supporting information, p. 17374 - 17387 (2021/10/25)
The activation of nitrosobenzene promoted by transition-metal complexes has gained considerable interest due to its significance for understanding biological processes and catalytic C-N bond formation processes. Despite intensive studies in the past decades, there are only limited cases where electron-rich metal centers were commonly employed to achieve the N-O or C-N bond cleavage of the coordinated nitrosobenzene. In this regard, it is significant and challenging to construct a suitable functional system for examining its unique reactivity toward reductive activation of nitrosoarene. Herein, we present a {Fe2S2} functional platform that can activate nitrosobenzene via an unprecedented iron-directed thiolate insertion into the N-O bond to selectively generate a well-defined diiron benzenesulfinamide complex. Furthermore, computational studies support a proposal that in this concerted four-electron reduction process of nitrosobenzene the iron center serves as an important electron shuttle. Notably, compared to the intact bridging nitrosoarene ligand, the benzenesulfinamide moiety has priority to convert into aniline in the presence of separate or combined protons and reductants, which may imply the formation of the sulfinamide species accelerates reduction process of nitrosoarene. The reaction pattern presented here represents a novel activation mode of nitrosobenzene realized by a thiolate-bridged diiron complex.
