15411-43-5Relevant articles and documents
Highly chemoselective reduction of aromatic nitro compounds by copper nanoparticles/ammonium formate
Saha, Amit,Ranu, Brindaban
, p. 6867 - 6870 (2008)
(Chemical Equation Presented) A highly chemoselective reduction of aromatic nitro compounds to the corresponding amino derivatives has been achieved by a combination of copper nanoparticles and ammonium formate in ethylene glycol at 120°C. The reductions are successfully carried out in presence of a wide variety of other reducible functional groups in the molecule, such as Cl, I, OCH2Ph, NHCH2Ph, COR, COOR, CN, etc. The reactions are very clean and high yielding.
Transforming nonselective into chemoselective metal catalysts for the hydrogenation of substituted nitroaromatics
Corma, Avelino,Serna, Pedro,Concepcion, Patricia,Calvino, Jose Juan
, p. 8748 - 8753 (2008)
It is generally accepted that good hydrogenation noble and nonnoble metal catalysts such as Pt, Ru, or Ni are not chemoselective for hydrogenation of nitro groups in substituted aromatic molecules. We have found that it is possible to transform nonchemoselective into highly chemoselective metal catalysts by controlling the coordination of metal surface atoms while introducing a cooperative effect between the metal and a properly selected support. Thus, highly chemoselective and general hydrogenation Pt, Ru, and Ni catalysts can be prepared by generating nanosized crystals of the metals on the surface of a TiO2 support and decorating the exposed (111) and (100) crystal faces by means of a simple catalyst activation procedure. By doing this, it has been possible to change the relative rate for hydrogenating competitive groups present in the molecule by almost 2 orders of magnitude, increasing the chemoselectivity from less than 1% to more than 95%.
Chemoselective Hydrogenation of Nitroaromatics at the Nanoscale Iron(III)–OH–Platinum Interface
Fu, Gang,Li, Laiyang,Ming, Jiang,Qin, Ruixuan,Ren, Juan,Wang, Yongke,Wang, Yu,Zhang, Wuyong,Zheng, Nanfeng,Zhou, Wenting
, p. 12736 - 12740 (2020)
Catalytic hydrogenation of nitroaromatics is an environment-benign strategy to produce industrially important aniline intermediates. Herein, we report that Fe(OH)x deposition on Pt nanocrystals to give Fe(OH)x/Pt, enables the selective hydrogenation of nitro groups into amino groups without hydrogenating other functional groups on the aromatic ring. The unique catalytic behavior is identified to be associated with the FeIII-OH-Pt interfaces. While H2 activation occurs on exposed Pt atoms to ensure the high activity, the high selectivity towards the production of substituted aniline originates from the FeIII-OH-Pt interfaces. In situ IR, X-ray photoelectron spectroscopy (XPS), and isotope effect studies reveal that the Fe3+/Fe2+ redox couple facilitates the hydrodeoxygenation of the -NO2 group during hydrogenation catalysis. Benefitting from FeIII-OH-Pt interfaces, the Fe(OH)x/Pt catalysts exhibit high catalytic performance towards a broad range of substituted nitroarenes.
Finely Controlled Platinum Nanoparticles over ZnO Nanorods for Selective Hydrogenation of 3-Nitrostyrene to 3-Vinylaniline
Gao, Tongtong,Liu, Zhong-Wen,Shi, Wen,Zhang, Bingsen,Zhang, Liyun,Zhang, Ying
, (2020)
Metallic platinum nanocatalysts play a key role in the liquid-phase selective hydrogenation of substrates with more than one unsaturated bond. However, the commonly applied explanation for the effects of different electronic and geometric properties of catalysts on reactions remains of a heuristic nature due to the difficulties involved in preparing catalysts with precise structure. In this work, we have directly loaded pre-synthesized metallic platinum nanoparticles onto well-structured ZnO nanorods and then subjected them to thermal treatment in a reductive atmosphere for different temperatures. The effects of the different electronic and geometric properties of the catalysts on the selective reduction of 3-nitrostyrene to 3-vinylaniline as a model reaction have been rigorously explored through an analysis of the catalyst structures and the activity and selectivity profiles. Both the electron transfer from zinc to platinum and the decreased platinum surface density as a result of the formation of PtZn intermetallic compounds are key factors for improving the selectivity for the desired 3-vinylaniline. Azobenzene was detected in the reaction with all the Pt/ZnO catalysts after 10–90 min, which indicates that the reaction follows a condensation mechanism.
Chemoselective hydrogenation of 3-nitrostyrene over Ag/TiO2-SiO2 catalyst in a flow reactor
Nuzhdin, Alexey L.,Bukhtiyarova, Galina A.,Lin, Tingting,Gerasimov, Evgeny Yu.,Bukhtiyarov, Valerii I.
, p. 553 - 555 (2019)
Hydrogenation of 3-nitrostyrene in a flow reactor over silver nanoparticles on TiO2-modified silica affords 3-vinylaniline with selectivity of 97% at the full conversion of the substrate.
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Wiley,Smith
, (1963)
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Metal–Organic Framework Mediated Cobalt/Nitrogen-Doped Carbon Hybrids as Efficient and Chemoselective Catalysts for the Hydrogenation of Nitroarenes
Sun, Xiaohui,Olivos-Suarez, Alma I.,Oar-Arteta, Lide,Rozhko, Elena,Osadchii, Dmitrii,Bavykina, Anastasiya,Kapteijn, Freek,Gascon, Jorge
, p. 1854 - 1862 (2017)
A Co@N-doped carbon (Co@NC) hybrid was synthesized by thermal decomposition of the metal–organic framework (MOF) ZIF-67 under N2 atmosphere. These hybrid materials exhibit outstanding catalytic activity and chemoselectivity for the conversion of a wide range of substituted nitroarenes to their corresponding anilines under relatively mild reaction conditions. The high catalytic performance is attributed to the formation of cobalt nanoparticles and to the presence of atomically dispersed Co species in close interaction with nitrogen-doped graphene. Both active species are formed in situ during the pyrolytic transformation of ZIF-67. The catalysts could be reused in consecutive runs, exhibiting a slightly lower activity ascribed to blockage of the active sites by strongly adsorbed reaction species. These results open up a pathway for the design of noble-metal-free solid catalysts for industrial applications.
Nitrogen and oxygen-doped metal-free carbon catalysts for chemoselective transfer hydrogenation of nitrobenzene, styrene, and 3-nitrostyrene with hydrazine
Fujita, Shin-Ichiro,Watanabe, Hiroyuki,Katagiri, Ayaka,Yoshida, Hiroshi,Arai, Masahiko
, p. 257 - 262 (2014)
An activated carbon (AC) was treated by hydrogen peroxide and ammonia to dope oxygen and nitrogen on its surface. The surface-functionalized AC catalysts were used for the transfer reduction of nitrobenzene, styrene, and 3-nitrostyrene by hydrazine hydrat
Erbium oxide as a novel support for palladium nanocatalysts with strong metal-support interactions: remarkable catalytic performance in hydrogenation reactions
Wang, Xin,Jiang, Yi-Fan,Liu, Ya-Nan,Xu, An-Wu
, p. 19901 - 19907 (2018)
Because of the active components, ultra small size, and the strong metal-support interaction (SMSI) between the metal and the support, noble metal/support nanocatalysts show high catalytic activity in chemical and photochemical reactions. Palladium is one
Design of highly active and chemoselective bimetallic gold-platinum hydrogenation catalysts through kinetic and isotopic studies
Serna, Pedro,Concepcion, Patricia,Corma, Avelino
, p. 19 - 25 (2009)
Kinetic model for the chemoselective hydrogenation of nitroaromatic compounds on Au/TiO2 has been established by combining the Hougen-Watson formalism and isotopic studies. It has been found that, with this catalyst, the controlling step corres
Base-Free Transfer Hydrogenation of Nitroarenes Catalyzed by Micro-Mesoporous Iron Oxide
Datta, Kasibhatta J.,Rathi, Anuj K.,Gawande, Manoj B.,Ranc, Vaclav,Zoppellaro, Giorgio,Varma, Rajender S.,Zboril, Radek
, p. 2351 - 2355 (2016)
An efficient and practical protocol for the transfer hydrogenation of nitroarenes was developed, which uses flower-shaped micro-mesoporous iron oxide (MMIO) with formic acid as the reducing agent and tris[(2-diphenylphosphino)-ethyl]phosphine as the ligand in the absence of an additional base. The recyclable catalytic system enables the reduction of the nitro group in a broad range of substrates to yield valuable amines and shows a high tolerance to sensitive functional groups.
One step synthesis of Pt-Co/TiO2 catalysts by flame spray pyrolysis for the hydrogenation of 3-nitrostyrene
Pisduangdaw, Sukanya,Mekasuwandumrong, Okorn,Fujita, Shin-Ichiro,Arai, Masahiko,Yoshida, Hiroshi,Panpranot, Joongjai
, p. 11 - 15 (2015)
Supported Pt-Co/TiO2 catalysts were prepared by single step flame spray pyrolysis with Pt at 0.5 wt.% and Co loadings varying at 0, 0.1, 0.2, and 0.5 wt.%. Their catalytic activity was tested in the selective hydrogenation of 3-nitrostyrene. Based on the infrared spectroscopy of adsorbed CO results, the addition of Co led to a higher amount of Pt terrace atoms being formed on the catalyst surface which promoted the selectivity towards ethylnitrobenzene. Nevertheless, the positive effect of Co addition can be observed when the catalysts were reduced at 500°C. Both hydrogenation activity and selectivity of vinylaniline over Pt-Co/TiO2 were drastically increased and surpassed those of monometallic Pt/TiO2 due to the strong interaction between Pt-Co and the migration of TiOx species.
Remarkable effect of alkalis on the chemoselective hydrogenation of functionalized nitroarenes over high-loading Pt/FeO:X catalysts
Wei, Haisheng,Ren, Yujing,Wang, Aiqin,Liu, Xiaoyan,Liu, Xin,Zhang, Leilei,Miao, Shu,Li, Lin,Liu, Jingyue,Wang, Junhu,Wang, Guofu,Su, Dangsheng,Zhang, Tao
, p. 5126 - 5131 (2017)
The chemoselective hydrogenation of substituted nitroarenes to form the corresponding functionalized anilines is an important type of reaction in fine chemistry, and the chemoselectivity is critically dependent on the rational design of the catalysts. Thi
Water-soluble NHC-stabilized platinum nanoparticles as recoverable catalysts for hydrogenation in water
Baquero, Edwin A.,Chaudret, Bruno,De Jesús, Ernesto,Flores, Juan C.,Gonzalez-Arellano, Camino,Ruiz-Varilla, Andrea M.
, p. 2874 - 2881 (2020)
The production of water-soluble and stable metallic nanoparticles that can act as recoverable catalysts still remains a challenge. Herein we report the behavior of a series of water-soluble platinum nanoparticles containing different sulfonated NHC ligands as recoverable catalysts for the hydrogenation of aromatic compounds in pure water. The NHC-protected nanoparticles are found to be active and, in general, can be reutilized with no loss of activity or selectivity, although differences are observed depending on the substitution of the NHC ligand or on the substrate being hydrogenated. Pt leaching was determined to be only 0.03-0.29%. TEM images reveal that the shape of the nanoparticles remains unaltered after catalysis. However, the size of the particles increased, although with no influence on their catalytic properties in many instances.
COPPER NANOPARTICLE BASED CHEMOSELECTIVE REDUCTION
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Paragraph 0047-0049, (2021/11/20)
The instant invention provides processes for a chemo selective reduction of a nitro group within a compound in the presence of other groups which can also be reduced. This aspect of the present invention provides an ammonia borane (AB) initiated chemoselective reduction process of a nitro group contained within a compound in the presence of a copper (Cu) nanoparticle based catalyst. The invention is also directed to Copper (Cu) nanoparticle (NP) based catalysts, selected from Cu/WOx, Cu/SiO2, and Cu/C; wherein x represents an integer having a value of from about 2 to about 3.5, used in the chemo selective reduction of a nitro group contained within a compound in the presence of other groups which can also be reduced.
Selective and Additive-Free Hydrogenation of Nitroarenes Mediated by a DMSO-Tagged Molecular Cobalt Corrole Catalyst
Sch?fberger, Wolfgang,Timelthaler, Daniel,Topf, Christoph
, p. 2114 - 2120 (2021/07/22)
We report on the first cobalt corrole that effectively mediates the homogeneous hydrogenation of structurally diverse nitroarenes to afford the corresponding amines. The given catalyst is easily assembled prior to use from 4-tert-butylbenzaldehyde and pyrrole followed by metalation of the resulting corrole macrocycle with cobalt(II) acetate. The thus-prepared complex is self-contained in that the hydrogenation protocol is free from the requirement for adding any auxiliary reagent to elicit the catalytic activity of the applied metal complex. Moreover, a containment system is not required for the assembly of the hydrogenation reaction set-up as both the autoclave and the reaction vessels are readily charged under a regular laboratory atmosphere.
Zeolite-Encaged Isolated Platinum Ions Enable Heterolytic Dihydrogen Activation and Selective Hydrogenations
Dai, Weili,Deng, Xin,Guan, Naijia,Li, Landong,Liu, Runze,Ma, Ding,Qin, Bin,Qin, Xuetao,Wu, Guangjun
supporting information, p. 20898 - 20906 (2021/12/14)
Understanding the unique behaviors of atomically dispersed catalysts and the origin thereof is a challenging topic. Herein, we demonstrate a facile strategy to encapsulate Ptδ+ species within Y zeolite and reveal the nature of selective hydrogenation over a Pt@Y model catalyst. The unique configuration of Pt@Y, namely atomically dispersed Ptδ+ stabilized by the surrounding oxygen atoms of six-membered rings shared by sodalite cages and supercages, enables the exclusive heterolytic activation of dihydrogen over Ptδ+···O2- units, resembling the well-known classical Lewis pairs. The charged hydrogen species, i.e., H+ and Hδ-, are active reagents for selective hydrogenations, and therefore, the Pt@Y catalyst exhibits remarkable performance in the selective hydrogenation of α,β-unsaturated aldehydes to unsaturated alcohols and of nitroarenes to arylamines.
