104-96-1Relevant articles and documents
Highly selective reduction of nitroarenes to anilines catalyzed using MOF-derived hollow Co3S4 in water under ambient conditions
Xu, Yong,Lv, Xiao-Jun,Chen, Yong,Fu, Wen-Fu
, p. 31 - 35 (2017)
We developed a new strategy for the efficient reduction of nitroarenes using sodium sulfide as reducing agent with MOF-derived Co3S4 as catalyst in water and at room temperature. The introduction of sodium sulfite enhanced the reactant conversion and product selectivity, and the as-synthesized catalyst was used repeatedly five times and retained its activity and selectivity. A wide spectrum of reducible functional moieties kept unaffected under the reaction conditions, and isotope labeling experiment showed the hydrogen atom was derived from water.
Indium as a reducing agent: Reduction of aromatic nitro groups
Moody, Christopher J.,Pitts, Michael R.
, p. 1028 - 1028 (1998)
Treatment of a range of aromatic nitro compounds with indium powder in aqueous ethanolic ammonium chloride results in selective reduction of the nitro groups; ester, nitrile, amide and halide substituents are unaffected.
Catalytic hydrogenation of sulfur-containing nitrobenzene over Pd/C catalysts: In situ sulfidation of Pd/C for the preparation of PdxSy catalysts
Zhang, Qunfeng,Xu, Wei,Li, Xiaonian,Jiang, Dahao,Xiang, Yizhi,Wang, Jianguo,Cen, Jie,Romano, Stephen,Ni, Jun
, p. 17 - 21 (2015)
The preparation of supported palladium sulfides catalysts has attracted much attention due to their good sulfur-resistant properties in the hydrogenation of sulfur-containing compounds. In this work, we unambiguously demonstrated that Pd/C catalyst could be in situ sulfided by organic sulfur-containing reactant molecules and the sulfidation was highly dependent on temperature. The in situ sulfidation of Pd/C catalyst was composed of a reaction of Pd with the sulfur derived from the cleavage of C-S bond of sulfur-containing reactant molecules, followed by a transformation to PdxSy at high temperatures (around 120 °C). The sulfided Pd/C catalyst could be used for at least 18 recycles without a significant loss in its activity during the hydrogenation of sulfur-containing nitrobenzene at 180 °C with 3 MPa H2, which could be attributed to the stable presence of Pd4S and Pd16S7.
Chemoselective nitro reduction and hydroamination using a single iron catalyst
Zhu, Kailong,Shaver, Michael P.,Thomas, Stephen P.
, p. 3031 - 3035 (2016)
The reduction and reductive addition (formal hydroamination) of functionalised nitroarenes is reported using a simple and bench-stable iron(iii) catalyst and silane. The reduction is chemoselective for nitro groups over an array of reactive functionalities (ketone, ester, amide, nitrile, sulfonyl and aryl halide). The high activity of this earth-abundant metal catalyst also facilitates a follow-on reaction in the reductive addition of nitroarenes to alkenes, giving efficient formal hydroamination of olefins under mild conditions. Both reactions offer significant improvements in catalytic activity and chemoselectivity and the utility of these catalysts in facilitating two challenging reactions supports an important mechanistic overlap.
Hexafluoro-2-propanol-assisted quick and chemoselective nitro reduction using iron powder as catalyst under mild conditions
Chen, Xu-Ling,Ai, Bai-Ru,Dong, Yu,Zhang, Xiao-Mei,Wang, Ji-Yu
, p. 3646 - 3649 (2017)
Hexafluoro-2-propanol as the promoter for the quick nitro reduction using a combination of iron powder and 2 N HCl aqueous solution is reported. This methodology has several positive features, as it is of room temperature, remarkably short reaction time. A wide range of substrates including those bearing reducible functional groups such as aldehyde, ketone, acid, ester, amide, nitrile, halogens, even allyl, propargyl and heterocycles are chemoselectively reduced in good to excellent yields, even on gram scale. Notably, the highly selective reduction of 3-nitrophenylboronic acid is achieved quantitatively. The reduction is also tolerant of common protecting groups, and aliphatic nitro compound, 1-nitrooctane can be reduced successfully.
The synergic effects at the molecular level in CoS2 for selective hydrogenation of nitroarenes
Wei, Zhongzhe,Mao, Shanjun,Sun, Fanfei,Wang, Jing,Mei, Bingbao,Chen, Yiqing,Li, Haoran,Wang, Yong
, p. 671 - 679 (2018)
Catalytic functionalized aniline formation from nitroarenes is a core technology in the synthesis of pharmaceuticals, agrochemicals, and fine chemicals. However, control of chemoselectivity still poses particular challenges with aromatic nitro substrates bearing one or more reducible groups. Here, we report the low-cost synthesis of a porous carbon supported CoS2 catalyst (CoS2/PC) and successfully apply the catalyst in the chemoselective hydrogenation of nitroarenes. For hydrogenation of 3-nitrostyrene, the catalyst furnishes a superior selectivity of 99% towards 3-aminostyrene at a conversion of >99%. Density functional theory calculations together with X-ray absorption fine structure spectroscopy reveal that terdentate and tetrahedral coordinated Co atoms in CoS2 (labeled as Co3 and Co4) are possible active sites. The face to face located Co3 and Co4 sites make the reaction rather local, and Co3 and Co4 sites are occupied by substrates and H2, respectively, which is beneficial to the superior activity and selectivity. The Co3-Co4 "synergic active site pair" in CoS2 makes the investigation of the synergic effects at the molecular level a reality on heterogeneous catalysts.
Shape Engineering of Biomass-Derived Nanoparticles from Hollow Spheres to Bowls through Solvent-Induced Buckling
Chen, Chunhong,Li, Xuefeng,Deng, Jiang,Wang, Zhe,Wang, Yong
, p. 2540 - 2546 (2018)
The realization of asymmetric hollow carbonaceous nanostructures remains a great challenge, especially when biomass is chosen as the carbon resource through hydrothermal carbonization (HTC). Herein, a simple and straightforward solvent-induced buckling strategy is demonstrated for the synthesis of asymmetric spherical and bowl-like carbonaceous nanomaterials. The formation of the bowl-like morphology was attributed to the buckling of the spherical shells induced by the dissolution of the oligomers. The bowl-like particles prepared through this solvent-driven approach demonstrated a well-controlled morphology and a uniform particle size of approximately 360 nm. The obtained nanospheres and nanobowls were loaded with CoS2 nanoparticles to act as heterogeneous catalysts for the selective hydrogenation of aromatic nitro compounds. As expected, the CoS2/nanobowls catalyst showed good tolerance to a wide scope of reducible groups and afforded both high activity and selectivity in almost all the tested substrates.
In Situ-Generated Co0-Co3O4/N-Doped Carbon Nanotubes Hybrids as Efficient and Chemoselective Catalysts for Hydrogenation of Nitroarenes
Wei, Zhongzhe,Wang, Jing,Mao, Shanjun,Su, Diefeng,Jin, Haiyan,Wang, Yihe,Xu, Fan,Li, Haoran,Wang, Yong
, p. 4783 - 4789 (2015)
The earth-abundant nanohybrids Co0/Co3O4@N-doped carbon nanotubes were fabricated via an efficient thermal condensation of d-glucosamine hydrochloride, melamine, and Co(NO3)2·6H2O. The hybrids furnish excellent catalytic activity and perfect chemoselectivity (>99%) for a wide range of substituted nitroarenes (21 examples) under relatively mild conditions. The high catalytic performance and durability is attributed to the synergistic effects between each component, the unique structure of graphene layers-coated Co0, and the electronic activation of doped nitrogen. Density functional calculations indicate that the inner Co0 core and N species on the carbon shell can significantly decrease the dissociation energies of H2, giving evidence of the ability of carbon shell in the hybrids to enable H2 activation. These results open up an avenue to design more powerful low-cost catalysts for industrial applications.
Reduction of nitroarenes using CO and H2O in the presence of a nanostructured cobalt oxide/Nitrogen-Doped Graphene (NGr) catalyst
Westerhaus, Felix A.,Sorribes, Ivn,Wienh?fer, Gerrit,Junge, Kathrin,Beller, Matthias
, p. 313 - 317 (2015)
The most common route to anilines is based on the reduction of the corresponding nitroarenes. In general, hydrogen is preferred as reducing agent and numerous catalytic systems are known to achieve such transformations. Besides, the use of CO/H2O as hydrogen source offers interesting possibilities for reductions. Carbon monoxide is a cheap and abundant chemical used on industrial scale for a variety of transformations. Although the reduction of nitroarenes with CO/H2O is known in the presence of noble-metal catalysts, earth-abundant inexpensive catalysts showing high selectivity have not yet been developed. In this respect, herein we present the use of a heterogeneous cobalt oxide catalyst (Co3O4/NGr@C), which is modified by nitrogen-doped graphene layers. Using this non-noble metal catalyst nitroarenes are reduced in high yields and good chemoselectivities.
A sulfur-tolerant phosphorus doped Pd/C catalyst for hydrogenation of 4-nitrothioanisole
Xiong, Renjie,Zhao, Wenqiang,Wang, Zhiqiang,Zhang, Minghui
, (2021)
In this paper, we report a new type of sulfur resistant hydrogenation catalyst, which was obtained by simply phosphating commercial Pd/C catalyst with triphenylphosphine under H2 atmosphere at 600 °C. At this temperature, no palladium phosphides formed in XRD patterns due to the low synthetic temperature. Element analysis, N2 adsorption-desorption and ICP characterizations show that only a small amount of P has been introduced into Pd, so the phosphorus doping does not change the pore size and surface area of pristine Pd/C. XPS characterization shows that P doping can effectively prevent the substrate adsorption on Pd surface, which relieves the sulfurization rate of Pd. Hence, the phosphorus doping catalyst can fully catalyze the 4-nitrothioanisole to 4-aminothioanisole and exhibits higher activity than Pd/C, which only has 70.9 % conversion. Moreover, the phosphorus doped Pd/C catalyst has better stability than Pd/C and its activity is almost unchanged during the recycle.
