Xn:Harmful;
106-40-1Relevant articles and documents
An efficient method for reduction of nitroaromatic compounds to the corresponding aromatic amines with NH2NH2·H2O catalysed by H2O2-treated activated carbon
Jiang, Yuqin,Suo, Huajun,Zhang, Dandan,Li, Xiyong,Sun, Yamin,Ren, Baoqi,Zhang, Weiwei,Xu, Guiqing
, p. 509 - 512 (2017)
An efficient and green protocol for the reduction of nitroaromatic compounds to the corresponding amines has been developed. The reduction catalyst system includes NH2NH2·H2O and H2O2-treated activated carbon. Without adding additional metals, the H2O2-treated activated carbon could be reused for many cycles without decreasing catalytic efficiency. The aromatic amines could be obtained in good to excellent yields.
Selective bromination of pyrrole derivatives, carbazole and aromatic amines with DMSO/HBr under mild conditions
Liu, Cong,Dai, Rongji,Yao, Guowei,Deng, Yulin
, p. 593 - 596 (2014)
Bromination of pyrrole derivatives, carbazole and aromatic amines using the DMSO/HBr system affords high yields of the corresponding bromo compounds. Temperature control used in the bromination of anilines helped to promote selective formation of mono- or di-brominated products. Simple operation, low toxicity and high selectivity make this a promising new procedure for the bromination of aromatic compounds.
Dual optimization approach to bimetallic nanoparticle catalysis: Impact of M1/M2 ratio and supporting polymer structure on reactivity
Udumula, Venkatareddy,Tyler, Jefferson H.,Davis, Donald A.,Wang, Hao,Linford, Matthew R.,Minson, Paul S.,Michaelis, David J.
, p. 3457 - 3462 (2015)
A dual optimization approach to nanoparticle catalysis is reported in which both the composition of a bimetallic nanoparticle and the electronic properties of the supporting polystyrene-based polymer can be varied to optimize reactivity and chemoselectivity in nitroarene reductions. Ruthenium-cobalt nanoparticles supported on polystyrene are shown to catalyze nitroarene reductions at room temperature with exceptional activity, as compared with monometallic ruthenium catalysts. Both the identity of the second metal and the M1/M2 ratio show a profound effect on the chemoselectivity of nitroarene reductions. These polymer-supported bimetallic catalysts are shown to react with nearly complete chemoselectivity for nitro group reduction over a variety of easily reducible functional groups. The electronic properties of the supporting polymer also have a significant impact on catalysis, in which electron-deficient polystyrenes enable 100% conversion to the aniline product in just 20 min at room temperature. Polymer effects are also shown to influence the mechanism of the reduction reaction, in addition to accelerating the rate, confirming the impact of the polymer structure on catalytic efficiency. These catalysts are easily prepared in a single step from commercial materials and can be readily recycled without loss of activity.
Regioselective and high-yielding bromination of phenols and anilins using N-bromosaccharin and amberlyst-15
Baharfar,Alinezhad,Azimi,Salehian
, p. 863 - 865 (2011)
A regioselective and facile conversion method for bromination of anilines and phenols using N-bromosaccharine in the presence of a catalytic amount of Amberlyst-15 lead to enhancement of the reaction rate and yielded brominated products in good to excellent yields and short reaction times.
Aerobic oxidation and oxidative bromination in aqueous medium using polymer anchored oxovanadium complex
Islam, Sk. Manirul,Molla, Rostam Ali,Roy, Anupam Singha,Ghosh, Kajari,Salam, Noor,Iqubal, Md. Asif,Tuhina
, p. 169 - 178 (2014)
Polymer anchored oxovanadium catalyst was synthesized and characterized. Its catalytic activity was evaluated for the oxidation of various primary and secondary alcohols with molecular oxygen under mild reaction conditions. This catalyst was also effective for the oxidative bromination reaction of organic substrates with 90-100% selectivity of mono substituted products with H 2O2/KBr at room temperature. The above reactions require low temperature, short time period and most importantly all the above reactions occur in aqueous medium. The developed catalyst can be facilely recovered and reused six times without significant decrease in activity and selectivity. 2014 Elsevier B.V. All rights reserved.
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 (2022)
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.]
A ruthenium bisoxazoline complex as a photoredox catalyst for nitro compound reduction under visible light
Jia, Wei-Guo,Cheng, Ming-Xia,Gao, Li-Li,Tan, Siu Min,Wang, Chao,Liu, Xiaogang,Lee, Richmond
, p. 9949 - 9953 (2019)
An unreported ruthenium(ii) complex containing bisoxazoline ligands has been synthesized and characterized. To test the catalytic ability of the ruthenium complex, the synthesis of anilines from nitro compounds in the presence of a mild reducing agent sodium borohydride and visible light has been developed. Mechanistic studies involving the experiment and DFT calculations suggest that the reaction could involve a radical pathway with the assistance of a photoredox catalyst.
Graphene-supported CoS2 particles: An efficient photocatalyst for selective hydrogenation of nitroaromatics in visible light
Ma, Ben,Wang, Yingyong,Tong, Xili,Guo, Xiaoning,Zheng, Zhanfeng,Guo, Xiangyun
, p. 2805 - 2812 (2017)
CoS2/graphene composites fabricated by a facile hydrothermal method exhibit excellent photocatalytic performance for selective hydrogenation of nitroaromatics to the corresponding aniline employing molecular hydrogen as a reducing agent under visible light irradiation (400-800 nm). The rate constant of the composite catalyst for nitrobenzene hydrogenation can achieve as high as 35.50 × 10-3 min-1 with a selectivity of 100% toward the target product under mild conditions (30°C and 0.25 MPa pressure of H2). The catalyst also shows high recyclability, and there is no decrease in the catalytic activity after five successive cycles. There exists a synergistic effect between the graphene support and the CoS2 particles: conductive graphene as the support can rapidly extract the photoexcited electrons and effectively suppress the recombination of photogenerated charges in CoS2 particles, and then improve the photocatalytic performance. The photocatalytic reduction of nitrobenzene over the CoS2/graphene catalyst to aniline occurs through the direct pathway in the presence of H2.
Polymer supported Nickel nanoparticles as recyclable catalyst for the reduction of nitroarenes to anilines in aqueous medium
Romanazzi, Giuseppe,Fiore, Ambra Maria,Mali, Matilda,Rizzuti, Antonino,Leonelli, Cristina,Nacci, Angelo,Mastrorilli, Piero,Dell'Anna, Maria Michela
, p. 31 - 38 (2018)
Polymer supported nickel nanoparticles, generated by calcination under nitrogen of a Ni(II) containing polyacrylamide, catalyzed the hydrogenation of nitroarenes to anilines in aqueous medium at room temperature in the presence of NaBH4. The protocol generally favored the formation of the desired aniline as single product in high yields with short reaction times and proved to be highly selective in the hydrogenation of halonitrobenzene to haloaniline, avoiding the formation of hydro-dehalogenated side-products. The catalyst displayed excellent recyclability over at least five cycles (which is not trivial for nickel nanoparticle based catalysts used in water) and no leaching of metal into solution occurred, that made the overall system eco-friendly and economic. STEM analyses revealed that the thermally formed Ni nanoparticles turned into cubic nanotwins under reaction conditions, which remained almost unchanged with the re-cycles.
Vilsmeier-haack bromination of aromatic compounds with KBr and N-bromosuccinimide under solvent-free conditions
Chakradhar,Roopa,Rajanna,Saiprakash
, p. 1817 - 1824 (2009)
Bromination of aromatic hydrocarbons is triggered by Vilsmeier-Haack reagent [N,N-dimethyl formamide (DMF-POCl3 system)] in the presence of KBr or N-bromosuccinimide (NBS) under solvent-free conditions by grinding the reactants in a mortar with a pestle. The reactions afforded corresponding bromo derivatives in very good yield with high regioselectivity. The results are comparable with those obtained under reflux conditions. Copyright Taylor & Francis Group, LLC.
A novel reduction of azides to amines with tellurium metal in near-critical water
Wang, Lei,Li, Pinhua,Chen, Jianhui,Yan, Jincan
, p. 1807 - 1813 (2003)
Tellurium metal in near-critical water (275°C) provides a novel and efficient method for the reduction of azides, producing amines in good yields.
Chemoselective reduction of halo-nitro aromatic compounds by β- cyclodextrin-modified transition metal catalysts in a biphasic system
Reetz, Manfred T.,Fr?mbgen, Christoph
, p. 1555 - 1557 (1999)
Transition metal complexes of a water-soluble β-cyclodextrin modified diphosphine can be used in the biphasic (H2O/organic) hydrogenation of halo- nitro aromatic compounds. The platinum complex is the most active and selective, resulting in the chemoselective formation of halo-aniline derivatives.
A new recyclable 1,4-bis(3-methylimidazolium-1-yl)butane ditribromide [bMImB]·(Br3)2 ionic liquid reagent for selective bromination of anilines or phenols and α-bromination of alkanones under mild conditions
Veisi, Hojat,Sedrpoushan, Alireza,Mohammadi, Pourya,Faraji, Ali Reza,Sajjadifar, Sami
, p. 25898 - 25903 (2014)
1,4-Bis(3-methylimidazolium-1-yl)butane ditribromide [bMImB] ·(Br3)2 has been synthesized and explored as a new efficient brominating agent. The crystalline ditribromide reagent is stable for months and acts as a safe source of bromine requiring just 0.5 equiv. for complete bromination. It has a high active bromine content per molecule and shows a remarkable reactivity toward various substrates in acetonitrile at room temperature. The prepared reagents were used as a green recyclable reaction media for the selective bromination of anilines, phenols and α-bromination of alkanones in excellent yields. The product can easily be isolated by just washing the highly water soluble 1,4-bis(3-methylimidazolium-1-yl)butane ditribromide [bMImB]·(Br3)2 from the brominated product. The spent reagent can be recovered, regenerated, and reused without any significant loss. the Partner Organisations 2014.
Efficient reduction of nitroarenes in water catalyzed by reusable Pd nanoparticles immobilized on chitosan-functionalized graphene oxide
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Graphene oxide was functionalized with chitosan for palladium immobilization (GO-Chit-Pd), which was used as an efficient catalyst for the reduction of aromatic nitro compounds using sodium borohydride in water. To achieve the best catalytic efficacy, various parameters such as temperature, solvent, mole ratio of hydrogen sources, and the amount of catalyst were optimized. The method has been applied to the reduction of a broad range of nitroarenes with different properties. The easy purification, convenient operation, environmental friendliness, and high product yields render this method viable for use. The nanocatalyst can be easily separated and efficiently recovered and reused for multiple cycles without appreciable loss in its catalytic activity.
A metal-free aerobic oxidative bromination of anilines and aryl ketones with 2-methylpyridinium nitrate as a reusable ionic liquid
Li, Ming-Fang,Wang, Jian,Ke, Yong-Xin,Pan, Song-Cheng,Yin, Hong,Du, Wenting,Li, Jing-Hua
, p. 267 - 270 (2020)
An aerobic oxidative bromination of anilines and aryl ketones catalyzed by recyclable 2-methylpyridinium nitrate ionic liquid is achieved in water using hydrobromic acid as the bromine source and molecular oxygen as the oxidant. The catalytic system shows good efficiency and atom economy.
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Zoretic
, p. 1867 (1975)
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Development of sustainable and efficient nanocatalyst based on polyoxometalate/nickel oxide nanocomposite: A simple and recyclable catalyst for reduction of nitroaromatic compounds
Kurbah, Sunshine Dominic
, p. 1487 - 1495 (2021)
In this paper, we report the synthesis and characterization of NiO@PolyMo nanocomposite. The newly synthesized nanocomposite was characterized by transmission electronmicroscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), and powder X-ray diffraction (XRD). The particle sizes of the NiO@PolyMo nanocatalyst are in the range of 10–20 nm. Powder XRD patterns show that the phase of NiO@PolyMo remains unaltered even after the functionalization of NiO. The lattice fringes of d = 0.20 nm were observed, which correspond to the (111) plane of NiO phase. The newly synthesized material shows excellent catalytic performance and good selectivity for reduction of nitroarenes. The advantages of the present protocols are mild, and can be carried out using water as a solvent, which is an eco-friendly benign.
Facile reduction of azides to the corresponding amines with metallic samarium and catalytic amount of iodine
Huang, You,Zhang, Yongmin,Wang, Yulu
, p. 1065 - 1066 (1997)
Samarium and a catalytic amount of iodine in methanol reduce alkyl and aryl azides to the corresponding amines, and aroyl, sulfonyl azides to the corresponding amides in good yields under neutral and mild condition.
A convenient method for bromination of aromatic amines
Reeves,King II
, p. 855 - 859 (1993)
Pyridinium hydrobromide perbromide has been used to monobrominate aromatic amines. The monobromo compounds are obtained in good yield and with only small amounts of polybromoination products.
Selective oxidation of sulfides and oxidative bromination of organic substrates catalyzed by polymer anchored Cu(II) complex
Islam,Roy, Anupam Singha,Mondal, Paramita,Tuhina, Kazi,Mobarak, Manir,Mondal, John
, p. 127 - 131 (2012)
A new polymer-anchored Cu(II) complex has been synthesized and characterized. The catalytic performance of the complex has been tested for the oxidation of sulfides and in oxidative bromination reaction with hydrogen peroxide as the oxidant. Sulfides have been selectively oxidized to the corresponding sulfoxides in excellent yields and in the presence of KBr as the bromine source, organic substrates have been selectively converted to mono bromo substituted compounds using polymer-anchored Cu(II) catalyst. This catalyst showed excellent catalytic activity, high selectivity, and recyclability. The polymer-anchored Cu(II) catalyst could be easily recovered by filtration and reused more than five times without appreciable loss of its initial activity.
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Greenfield,Dovell
, p. 3670 (1967)
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Copper(II) complex with oxazoline ligand: Synthesis, structures and catalytic activity for nitro compounds reduction
Du, Jun,Gao, Li-Li,Jia, Wei-Guo,Li, Mei,Zhi, Xue-Ting
, (2020)
The Cu(II) complexes bearing bisoxazolines, tridentate pincer pybox and terpyridine ligands have been synthesized and fully characterized. The molecular structures of copper complexes 1a and 1c were confirmed by single-crystal X-ray diffraction methods. These copper complexes highly catalyzed nitro compounds reduction to aniline and its derivatives in the presence of NaBH4 reducing agent in water solvent. The complex 1e was an efficient catalyst toward nitro compounds reduction with wide functional group substrate scope and aliphatic nitro compounds.
Polymer-anchored [Fe(III)Azo] complex: An efficient reusable catalyst for oxidative bromination and multi-components reaction for the synthesis of spiropiperidine derivatives
Khatun, Resmin,Biswas, Surajit,Ghosh, Swarbhanu,Islam, Sk. Manirul
, p. 37 - 46 (2018)
A heterogeneous catalyst was prepared by attaching Fe(III) into organically modified chloromethylated polytstyrene and characterized by AAS, IR, PXRD, TG-DTA, UV–Vis, and SEM studies. In presence of H2O2 and KBr as bromine source, the catalyst showed remarkably high conversion with para-selectivity towards the oxidative bromination reaction in acetic acid medium. The catalyst was also very active and highly efficient for the production of spiropiperidine derivatives through multi-component reaction in isopropyl alcohol at room temperature. The catalyst was not leached during the catalytic reactions, moreover, after five cycles the catalytic activity and selectivity of the catalyst were not decreased very significantly.
Synthesis, crystal structure and reactivity of homobimetallic vanadium(V) complexes derived from oxaloyldihydrazone ligands
Syiemlieh, Ibanphylla,Asthana, Mrityunjaya,Kurbah, Sunshine D.,Lal, Ram A.
, p. 202 - 216 (2019)
Treatment of V2O5 with dihydrazone ligands (H4L) (disalicylaldehydeoxaloyldihydrazone (H4L1 = H4slox), bis(2-hydroxy-1-naphthaldehyde)oxaloyldihydrazone (H4L2 = H4nph) and bis(5-bromosalicylaldehyde)oxaloyldihydrazone (H4L3 = H4sloxBr)) in methanol leads to the formation of homobimetallic vanadium(V) complexes of the composition [(CH3)2NH2]2[(VO2)2(L)]·nH2O, where n = 2 (1, 2) and n = 4 (3). The reaction of complexes 1–3 with H2O2 results in the formation of bis(monooxidoperoxidovanadate(V)) complexes[{VO(O2)}2(L)]2? and the reaction with HCl leads to the formation of oxidohydroxido species of the composition [(VO(OH)(L)]2?. The complexes show great potential for the oxidation of alcohols and the oxidative bromination of some organic substrates.
Copper catalyzed synthesis of 1-aryl-1,2,3-triazoles from aryl iodides, alkynes, and sodium azide
Chen, Ying,Zhuo, Zi-Jian,Cui, Dong-Mei,Zhang, Chen
, p. 215 - 218 (2014)
Aryl azides were synthesized using heterogeneous porous Cu (0) catalyst via a coupling reaction of aryl iodides with sodium azide under mild conditions. Under the same conditions, one-pot Cu-catalyzed azide-alkyne cycloaddition of aryl iodides, alkynes, and sodium azide yielded 1-aryl-1,2,3-triazoles.
Moderated Basicity of Endohedral Amine Groups in an Octa-Cationic Self-Assembled Cage
Hooley, Richard J.,Julian, Ryan R.,Mueller, Leonard J.,Ngai, Courtney,Williams, Christopher G.,Wu, Hoi-Ting,da Camara, Bryce
supporting information, (2022/02/01)
A self-assembled FeII4L6 cage was synthesized with 12 internal amines in the cavity. The cage forms as the dodeca-ammonium salt, despite the cage carrying an overall 8+ charge at the metal centers, extracting protons from displaced water in the reaction. Despite this, the basicity of the internal amines is lower than their counterparts in free solution. The 12 amines have a sliding scale of basicity, with a ≈6 pKa unit difference between the first and last protons to be removed. This moderation of side-chain basicity in an active site is a hallmark of enzymatic catalysis.
Designing of Highly Active and Sustainable Encapsulated Stabilized Palladium Nanoclusters as well as Real Exploitation for Catalytic Hydrogenation in Water
Patel, Anish,Patel, Anjali
, p. 803 - 820 (2020/08/12)
Abstract: Encapsulated nanoclusters based on palladium, 12-tunstophosphoric acid and silica was designed by simple wet impregnation methodology. The catalyst was found to be very efficient towards cyclohexene hydrogenation up to five catalytic runs with substrate/catalyst ratio of 4377/1 at 50?°C as well as for alkene, aldehyde, nitro and halogen compounds. Graphic Abstract: Silica encapsulated Pd nanoclusters stabilized by 12-tungstophosphoric acid is proved to be sustainable and excellent for water mediated hydrogenation reaction with very high catalyst to substrate ratio as well as TON.[Figure not available: see fulltext.]
