104-94-9Relevant articles and documents
Synthesis, structures and catalytic activities of half-sandwich ruthenium complexes based on Schiff Base ligands
Jia, Wei-Guo,Zhang, Hui,Zhang, Tai,Ling, Shuo
, p. 15 - 18 (2016)
A series of half-sandwich ruthenium(II) complexes containing Schiff-base ligands [Ru(p-cymene)LCl] [HL = (E)-4-X-2-((phenylimino)methyl)phenol, X = H (2a); X = CH3 (2b); X = Cl (2c) and X = Br (2d)] have been synthesized and fully characterized by 1H and 13C NMR spectra, elemental analyses and infrared spectrometry. Moreover, the molecular structures of ruthenium complexes 2b and 2c were confirmed by single-crystal X-ray diffraction methods. These half-sandwich ruthenium complexes are highly catalyzed hydrogenation of nitroarenes to aromatic anilines to proceed in the presence of sodium borohydride reducing agent in ethanol solvent. Notably, complex 2c was found to be a very efficient catalyst toward reduction of nitroarene compounds with wide functional group compatibility and substrate scope.
Sonication and Microwave-Assisted Primary Amination of Potassium- Aryltrifluoroborates and Phenylboronic Acids under Metal-Free Conditions
Kuik, Dale,McCubbin, J. Adam,Tranmer, Geoffrey K.
, p. 2555 - 2561 (2017)
The transition-metal-free generation of a series of primary arylamines from potassium aryltrifluoroborates and phenylboronic acids- is reported. The method uses a mild, inexpensive source of nitrogen (hydroxylamine-O-sulfonic acid) in cooperation with aqueous sodium hydroxide in acetonitrile. Both a sonication and a microwave-assisted method were developed, which are capable of converting ArBF3K functionalities into primary arylamines (ArNH2) in isolated yields of up to 78% (10 examples for each method). This report represents the first general method for the conversion of aryltrifluoroborates into primary arylamines under mild, transition-metal-free conditions in moderate to very good yields. The method is applicable to a wide array of substrates containing electron-donating, electron-neutral, or electron-withdrawing substituents. Both the sonication and microwave methods were also applied to the generation of anilines from phenylboronic acids in isolated yields of up to 96% (12 examples for each method) that were superior to existing room temperature methods in terms of yield, while also offering much shorter reaction times (15 min vs 16 h). In particular, the microwave method is the first to allow for the conversion of arylboronic acids containing strongly electron-withdrawing substituents into the corresponding anilines in good yields, along with electron-donating- substituents in very good to excellent yields.
Atomically dispersed Ni as the active site towards selective hydrogenation of nitroarenes
Yang, Fan,Wang, Minjian,Liu, Wei,Yang, Bin,Wang, Ying,Luo, Jun,Tang, Yushu,Hou, Liqiang,Li, Yun,Li, Zihui,Zhang, Bing,Yang, Wang,Li, Yongfeng
, p. 704 - 711 (2019)
Rational design of heterogeneous non-noble metal catalysts as highly efficient and selective catalysts for hydrogenation of nitroarenes with hydrogen as the reducing agent is currently a great challenge, which has attracted a great deal of attention. Herein, a new strategy for achieving atomic dispersion of Ni atoms on nitrogen-doped porous carbon (Ni-N-C) with a specific surface area of up to 810 m2 g-1 and nickel loading as high as 4.4 wt% is developed, yielding high activity, chemoselectivity, and reusability of catalysts in the hydrogenation of nitroarenes using hydrogen as the reductant with a turnover of number (TON) value of 84 and a turnover of frequency (TOF) value of 8.4 h-1 for the first time. The Ni single atoms anchored on N-doped porous carbon by binding with nitrogen/carbon have been proved to be the active sites. Importantly, the Ni-N3 active species is found to contribute more activity compared with Ni-N2 and Ni-N4. Density functional theory (DFT) calculations also reveal that the Ni-N3 structure exhibits the highest activity according to the lowest adsorption energy and the longest elongation N-O bonds of nitrobenzene, which originated from the induced charge transfer. This work opens a new route for rational design and accurate modulation of nanostructured organic molecular transformation catalysts at the atomic scale.
A new linker for anchoring/masking primary amines on solid support
Paladino, Antonietta,Mugnaini, Claudia,Botta, Maurizio,Corelli, Federico
, p. 565 - 568 (2005)
(Chemical Equation Presented) A polymer-supported diketone was synthesized and used to fully protect/mask primary amines by the formation of a pyrrole ring. Various reactions can be performed on this system which then can be cleaved with full restoration of the amine functionality. The resin can also be recycled at least once without loss of purity of the final compound.
Electrophilic amination of aromatics with sodium azide in BF3-H2O
Prakash, G.K. Surya,Gurung, Laxman,Marinez, Eric R.,Mathew, Thomas,Olah, George A.
, p. 288 - 291 (2016)
Boron trifluoride monohydrate is an excellent Br?nsted acid catalyst system for a wide range of reactions. It is a non-oxidizing acid catalyst prepared easily by bubbling BF3 into water. We have found boron trifluoride monohydrate/sodium azide combination to be an efficient reagent system for aromatic electrophilic amination. The present method avoids the use of expensive superacids such as trifluoromethanesulfonic acid and provides a facile access to aromatic amines directly from aromatics.
Regio- and chemoselective catalytic transfer hydrogenation of aromatic nitro and carbonyl as well as reductive cleavage of azo compounds over novel mesoporous NiMCM-41 molecular sieves
Mohapatra, Susanta K.,Sonavane, Sachin U.,Jayaram, Radha V.,Selvam, Parasuraman
, p. 4297 - 4300 (2002)
(equation presented) Regio-and chemoselective reduction of nitroarenes and carbonyl compounds and reductive cleavage of azo compounds, including bulkier molecules, was achieved by the catalytic transfer hydrogenation method (CTH) using a novel nickel-containing mesoporous silicate (NiMCM-41) molecular sieve catalyst. In addition, the catalyst was also found to behave as a truly heterogeneous catalyst as the yield was practically unaffected.
Cobalt-modified molybdenum carbide as an efficient catalyst for chemoselective reduction of aromatic nitro compounds
Zhao, Zhongkui,Yang, Hongling,Li, Yu,Guo, Xinwen
, p. 1274 - 1281 (2014)
This work presents a facile and clean transformation for synthesizing diverse functionalized arylamines through chemoselective reduction reaction of their corresponding substituted nitroarenes catalyzed by the supported cobalt-promoted molybdenum carbide catalyst on modified activated carbon (Co-Mo2C/AC, AC is denoted as the modified activated carbon by H 2O2 oxidation treatment). Various characterization techniques including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma (ICP) and H2 temperature-programmed reduction (H2-TPR) were employed to reveal the relationship between catalyst nature and catalytic performance, and the plausible reaction mechanism is also proposed. The characterization results suggest that the addition of a small amount of transition metals, especially cobalt could significantly promote the formation of a perfect molybdenum carbide crystal phase, resulting in the improvement in catalytic properties of the supported molybdenum carbide catalyst. Reaction results demonstrate that the optimized Co-Mo2C/AC catalyst shows comparable catalytic performance towards precious metals for chemoselective reduction of various aromatic nitro compounds, affording 100% yield for all substrates involved in this work (99.3% of isolated yield for model substrate). Moreover, it can be found that the catalyst could be easily recovered by filtration and recycled without obvious loss in its catalytic properties. Therefore, the developed Co-Mo2C/AC catalyst in this work can be considered as an industrially viable and cheap candidate for clean and highly-efficient production of diverse functionalized arylamines.
Development of Bu3SnH-Catalyzed Processes: Efficient Reduction of Azides to Amines
Hays, David S.,Fu, Gregory C.
, p. 2796 - 2797 (1998)
-
A novel and efficient production of amines from azides using LiCl/NaBH4
Raja Ram,Purushothama Chary,Iyengar
, p. 4495 - 4500 (2000)
A practical and efficient reagent system LiCl/NaBH4 is used for the production of amines from azides is described.
Electrophilic Amination of Higher Order Cuprates with N,O-Bis(trimethylsilyl)hydroxylamine
Casarini, Antonella,Dembech, Pasquale,Lazzari, Dario,Marini, Elisabetta,Reginato, Gianna,et al.
, p. 5620 - 5623 (1993)
In the reaction of higher order cyanocuprates with N,O-bis(trimethylsilyl)hydroxylamine delivery of the NHSiMe3 moiety to one of the anionic ligands in the cuprate takes place even in the absence of external bases according to an "electrophilic amination" protocol.Details of the methodology are given, and the reaction mechanism is analyzed in terms of interception by a mixed bis-metal cluster of a lithium N-silyl-N-siloxyamide, followed by intramolecular C-N coupling.This method is applicable to cyanocuprates bearing aromatic, heteroaromatic, and saturated aliphatic ligands.A number of 2-amino-substituted heterocycles, not easily accesible by normal routes, can be obtained with the aid of a stabilizing silylation at the nitrogen atom.
Palladium-modified functionalized cyclodextrin as an efficient and recyclable catalyst for reduction of nitroarenes
Guo, Yafei,Li, Jiuling,Zhao, Fen,Lan, Guineng,Li, Liang,Liu, Yuqi,Si, Yunsen,Jiang, Yubo,Yang, Bo,Yang, Rui
, p. 7950 - 7954 (2016)
A palladium-modified functionalized cyclodextrin (DACH-Pd-β-CD) catalytic system was synthesized and characterised. It showed high catalytic performance in the reduction of different nitroarenes to the corresponding anilines with the presence of sodium borohydride in water at room temperature. The yields of the desired products are up to 99%. Furthermore, the catalyst can be easily separated and still could maintain high catalytic activity after five cycles and no leaching of Pd into solution occurred.
Highly dispersed Pt in MIL-101: An efficient catalyst for the hydrogenation of nitroarenes
Du, Weichen,Chen, Gongzhou,Nie, Renfeng,Li, Yingwei,Hou, Zhaoyin
, p. 56 - 59 (2013)
Homogeneously dispersed Pt adatoms were fabricated in ordered mesoporous metal-organic framework (MIL-101) through a simple colloid method. N 2-adsorpton and time-resolved HRTEM analysis disclosed that Pt dispersed highly in the pores and/or ou
An abnormal N-heterocyclic carbene based nickel complex for catalytic reduction of nitroarenes
Vijaykumar, Gonela,Mandal, Swadhin K.
, p. 7421 - 7426 (2016)
Herein we report the synthesis of a nickel(ii) dichloro complex bearing an abnormal N-heterocyclic carbene (aNHC). The NiCl2(aNHC)2 complex has been used as an efficient catalyst for the reduction of nitroarenes with hydrosilanes to give aromatic amines in good to excellent yields. This catalytic protocol can tolerate functional groups such as halides, alkenes or nitriles. Furthermore, the longevity of the catalyst was tested in successive catalytic cycles, which indicates a sustained catalytic activity over multiple catalytic cycles.
Simple and efficient CuI/PEG-400 system for amination of aryl halides with aqueous ammonia
Chen, Junmin,Yuan, Tangjun,Hao, Wenyan,Cai, Mingzhong
, p. 3710 - 3713 (2011)
The cross-coupling reaction between aryl halides with aqueous ammonia was efficiently catalyzed in CuI/PEG-400 System with high yield. A range of electron-withdrawing or electron-donating aryl iodides and bromides were found to be applicable to the environmentally benign system. The process allows assembly of primary arylamines in great diversity which bear a wide range of functional groups including cyano, nitro, acetyl, ether, or amino moiety.
Synthesis, characterization, and catalytic activity of half-sandwich ruthenium complexes with pyridine/phenylene bridged NHC = E (NHC = N-heterocyclic carbene, E = S, Se) ligands
Jia, Wei-Guo,Du, Teng-Teng,Gao, Li-Li,Du, Jun
, (2020)
Three half-sandwichruthenium(II) complexes with pyridine/phenylene bridged NHC = E (NHC = N-heterocyclic carbene, E = S, Se) ligands [Ru(p-cymene)L](PF6)1–2 (1a–1c, L = ligand) were synthesized and characterized. All ruthenium complexes were fully characterized by 1H and 13C NMR spectra, mass spectrometry, and single-crystalX-ray diffraction methods. Moreover, the half-sandwich ruthenium complexes with NHC = E ligands showed highly catalytic activities towards to the tandem dehydrogenation of ammonia borane (AB) and hydrogenation of R–NO2 to R–NH2 at 353 K in water.
Manganese Catalyzed Hydrogenation of Azo (N=N) Bonds to Amines
Ben-David, Yehoshoa,Das, Uttam Kumar,Diskin-Posner, Yael,Kar, Sayan,Milstein, David
, p. 3744 - 3749 (2021)
We report the first example of homogeneously catalyzed hydrogenation of the N=N bond of azo compounds using a complex of an earth-abundant-metal. The hydrogenation reaction is catalyzed by a manganese pincer complex, proceeds under mild conditions, and yields amines, which makes this methodology a sustainable alternative route for the conversion of azo compounds. A plausible mechanism involving metal-ligand cooperation and hydrazine intermediacy is proposed based on mechanistic studies. (Figure presented.).
-
Alvernhe,Laurent
, p. 1007 (1972)
-
Sodium hydroxide-catalyzed transfer hydrogenation of carbonyl compounds and nitroarenes using ethanol or isopropanol as both solvent and hydrogen donor
Wang, Dong,Deraedt, Christophe,Ruiz, Jaime,Astruc, Didier
, p. 14 - 21 (2015)
The development of a clean and renewable energy carrier has become a subject of high priority, and new catalytic system that involves both abundant and cheap catalysts and green solvents is highly desirable in terms of practical and sustainable chemistry. In this spirit, sodium hydroxide-catalyzed transfer hydrogenation of carbonyl compounds using ethanol as both hydrogen source and solvent is developed in this report. The process is successfully utilized in the hydrogenation of various ketones and aldehydes, and the corresponding primary and secondary alcohols are synthesized with excellent conversions. Furthermore, sodium hydroxide also smoothly promotes the transfer hydrogenation of nitroarenes providing anilines and azobenzenes. For both carbonyl compounds and nitroarenes, results in ethanol and isopropanol are compared, and a remarkable change of selectivity between these two solvents is disclosed for the NaOH-catalyzed transfer hydrogenation to nitroarenes.
Conventional and microwave assisted hydrogenolysis using zinc and ammonium formate
Srinivasa,Babu, S. N. Narendra,Lakshmi,Gowda, D. Channe
, p. 1831 - 1837 (2004)
The selective deprotection of several N-Bzl amino derivatives to the corresponding amines and the removal of S-Bzl and O-Bzl groups from the protected amino acids with ammonium formate and commercial zinc dust are reported. Many other reducible or hydrogenolysable substituents such as halogens, methoxy, phenol, ester, acid, ethene, and Boc groups are unaffected.
Novel and efficient hydrogenative cleavage of azo compounds to amine(s) using chitosan-supported formate and magnesium
Yu,Ma,Jin,Zhen
, p. 707 - 713 (2014)
A convenient and efficient method for the hydrogenative cleavage of azo compounds to corresponding amine (s) using chitosan-supported formate as hydrogen donor in conjunction with low-cost magnesium powder is reported. This method was found to be highly facile with selectivity over several other functional groups, such as halogen, alkene, nitrile, carbonyl, ether, amide, methoxy, and hydroxyl groups. Furthermore, this mild, exceedingly efficient, and highly chemoselective method simplifies the handling and separation procedures. Copyright
PdCu nanoparticles supported on graphene: An efficient and recyclable catalyst for reduction of nitroarenes
Feng, Yi-Si,Ma, Jing-Jing,Kang, Yu-Mei,Xu, Hua-Jian
, p. 6100 - 6105 (2014)
Graphene supported PdCu bimetallic nanoparticles were synthesized through coreduction of PdCl2and CuCl2·H2O. X-ray diffraction (XRD), X-ray photoelectron (XPS) and transmission electron microscopy (TEM) were performed to characterize the structures. The complex could be used as an efficient catalyst for reduction of nitroarenes to the corresponding anilines in the presence of NaBH4and recycled up to six runs without significant loss of activity.
Regioselective Synthesis of 5-Trifluoromethyl Pyrazoles by the [1+4] Cyclization of Phenylhydrazones with N-Aryl Trifluoroacetimidoyl Iodides
Yu, Hong-Bin,Huang, Wei-Yuan
, p. 679 - 680 (1997)
Treatment of the phenylhydrazone of a methyl ketone (2) or cyclohexanone (3) with N-aryl trifluoroacetimidoyl iodide (1) in the presence of excess sodium hydride resulted in a [1+4] cyclization to give 5-trifluoromethyl pyrazoles (4, 5) regioselectively. The structure of products 4 or 5 was confirmed by the 13C NMR spectra.
Inhibition of Acid-induced decomposition of diphenyltriazenes by complexation with cyclodextrins
Xu, Tingting,Asadi, Atefeh Vaez-Zadeh,Barra, Monica
, p. 567 - 574 (2010)
Acid-promotedN Nbond cleavage in 1,3-diphenyltriazenes (X-Ph-N=N-NH-Ph-X X = H, 4-OCH3), leading to formation of diazonium ions and anilines, is strongly inhibited in aqueous solutions in the presence of cyclodextrins (CDs). The inhibition is ascribed to the formation of inclusion complexes that render the guest diphenyltriazene significantly less basic as a result of the less polar nature of the CD cavity (amicrosolvent effect). Association equilibrium constants for 1:1 host-guest complexes increase in the order α-CD 3 being larger than those for X = H. In the case of α-CD, formation of 2:1 host-guest complexes is also involved.
Chemoselective hydrogenation of functionalized nitroarenes and imines by using carbon nanofiber-supported iridium nanoparticles
Motoyama, Yukihiro,Taguchi, Masahiro,Desmira, Nelfa,Yoon, Seong-Ho,Mochida, Isao,Nagashima, Hideo
, p. 71 - 74 (2014)
The reaction of three types of carbon nanofibers (CNFs; platelet: CNF-P, tubular: CNF-T, herringbone: CNF-H) with Ir4(CO)12 in mesitylene at 165 °C provided the corresponding CNF-supported iridium nanoparticles, Ir/CNFs (Ir content=2.3-2.6 wt. %). Transmission electron microscopy (TEM) studies of these Ir/CNF samples revealed that size-controlled Ir nanoparticles (average particle size of 1.1-1.5 nm) existed on the CNFs. Among the three Ir/CNF samples, Ir/CNF-T showed an excellent catalytic activity and chemoselectivity towards hydrogenation of functionalized nitroarenes and imines; the corresponding aniline derivatives were obtained with high turnover numbers at ambient temperature under 10 atm of H2, and the catalyst is reusable. Ir/CNF-T was also effective for the reductive N-alkylation of anilines with carbonyl compounds.
Superior activity and selectivity of heterogenized cobalt catalysts for hydrogenation of nitroarenes
Li, Wu,Artz, Jens,Broicher, Cornelia,Junge, Kathrin,Hartmann, Heinrich,Besmehn, Astrid,Palkovits, Regina,Beller, Matthias
, p. 157 - 162 (2019)
The development of improved catalysts for highly selective hydrogenation of nitroarenes is described. For this purpose Co nanoparticles were supported on ordered mesoporous carbon CMK-3 and characterized in detail. The optimal CMK-3-CoPc catalyst exhibits excellent hydrogenation activity for several (hetero)aromatic nitro compounds and yielded the corresponding anilines under mild conditions (40 °C, 20 bar H2).
Nickel Boride Catalyzed Reductions of Nitro Compounds and Azides: Nanocellulose-Supported Catalysts in Tandem Reactions
Proietti, Giampiero,Prathap, Kaniraj Jeya,Ye, Xinchen,Olsson, Richard T.,Dinér, Peter
supporting information, p. 133 - 146 (2021/11/04)
Nickel boride catalyst prepared in situ from NiCl2 and sodium borohydride allowed, in the presence of an aqueous solution of TEMPO-oxidized nanocellulose (0.01 wt%), the reduction of a wide range of nitroarenes and aliphatic nitro compounds. Here we describe how the modified nanocellulose has a stabilizing effect on the catalyst that enables low loading of the nickel salt pre-catalyst. Ni-B prepared in situ from a methanolic solution was also used to develop a greener and facile reduction of organic azides, offering a substantially lowered catalyst loading with respect to reported methods in the literature. Both aromatic and aliphatic azides were reduced, and the protocol is compatible with a one-pot Boc-protection of the obtained amine yielding the corresponding carbamates. Finally, bacterial crystalline nanocellulose was chosen as a support for the Ni-B catalyst to allow an easy recovery step of the catalyst and its recyclability for new reduction cycles.
Chemo-, site-selective reduction of nitroarenes under blue-light, catalyst-free conditions
Liang, Yong,Lu, Changsheng,Lu, Shuo,Ma, Jiawei,Ren, Hongyuan,Wang, Bin,Xu, Jingkai,Yan, Hong
supporting information, p. 2420 - 2424 (2021/12/13)
The tandem reaction of photoinduced double hydrogen-atom transfer and deoxygenative transborylation for chemo- and site-selective reduction of nitroarenes into aryl amines under catalyst-free, room temperature conditions was disclosed in excellent yields. In this reaction, isopropanol (iPrOH) was used as hydrogen donor and tetrahydroxydiboron [B2(OH)4] as deoxygenative reagent with green, cheap, and commercially available credentials. In particular, a wide range of reducible functional groups such as halogen (-Cl, -Br and even -I), alkenyl, alkynyl, aldehyde, ketone, carboxyl, and cyano are all tolerated. Moreover, the reaction preferentially reduces the nitro group at the electron-deficient site over another nitro group in the same molecule. A detailed mechanistic investigation in combination of experiments and theoretical calculations gave a reasonable explanation for the reaction pathway.
