103-32-2Relevant articles and documents
Zinc-Catalyzed N-Alkylation of Aromatic Amines with Alcohols: A Ligand-Free Approach
Sankar, Velayudham,Kathiresan, Murugavel,Sivakumar, Bitragunta,Mannathan, Subramaniyan
, p. 4409 - 4414 (2020)
An efficient zinc-catalyzed N-alkylation reaction of aromatic amines was achieved using aliphatic, aromatic, and heteroaromatic alcohols as the alkylating reagent. A variety of aniline derivatives, including heteroaromatic amines, underwent the N-alkylation reaction and furnished the corresponding monoalkylated products in good to excellent yields. The application of the reaction is also further demonstrated by the synthesis of a 2-phenylquinoline derivative from acetophenone and 2-aminobenzyl alcohol. Deuterium labeling experiments show that the reaction proceeds via a borrowing hydrogen process. (Figure presented.).
Pollak,Grillot
, p. 2892 (1967)
Ti?Pd Alloys as Heterogeneous Catalysts for the Hydrogen Autotransfer Reaction and Catalytic Improvement by Hydrogenation Effects
Takahashi, Yuya,Kondo, Ryota,Utsunomiya, Masayoshi,Suzuki, Takeyuki,Takeshita, Hiroyuki T.,Obora, Yasushi
, p. 2432 - 2437 (2019)
Ti?Pd alloys were investigated as heterogeneous catalysts for hydrogen autotransfer reactions. This is the first reported study of alloys as catalysts for hydrogen-borrowing reactions using alcohols. We improved the catalytic activities of alloys by increasing their specific surface areas via a hydrogenation?powdering process. The reactivities and selectivities of hydrogenated Ti?Pd alloys [Ti?Pd(Hy)] were higher than those of non-hydrogenated alloy catalysts in N-alkylation by hydrogen autotransfer using alcohols. A plausible catalytic cycle is proposed based on control studies and deuterium labelling experiments.
Zirconium-mediated intramolecular coupling reactions of unsaturated anilines. Diastereoselective synthesis of azetidines
Barluenga, Jose,Sanz, Roberto,Fananas, Francisco J.
, p. 5953 - 5958 (1997)
Imine complexes of zirconocene, generated by a β-hydrogen abstraction process, which possess a carbon-carbon multiple bond, undergo inter- or intramolecular carbometalation to afford 1,4-cyclohexanediamine or cycloalkylaniline derivatives depending on the relative position of the unsaturated moiety with respect to the imine complex. A new diastereoselective synthesis of azetidines has been developed by treatment of azazirconacyclopentanes with iodine.
Titanium promoted reduction of imines with Grignards, silanes, and zinc: Identification of a new mechanism with silanes
Kumar, Akshai,Pandiakumar, Arun Kumar,Samuelson
, p. 3185 - 3190 (2014)
Aldimines react with reducing agents, such as Grignards, phenylsilane or zinc in the presence of titanium(IV) isopropoxide to form amines and reductively coupled imines (diamines). Using deuterium labeled reagents, the mechanism of reduction to form amine
Isomerization of meso diamines into their C2 symmetrical d,l isomers
Alexakis, Alexandre,Aujard, Isabelle,Mangeney, Pierre
, p. 875 - 876 (1998)
An efficient isomerization method is disclosed which allows the obtention of the useful d,l isomers of C2 symmetrical diamines, starting from their meso isomer.
Self-Suspended Nanoparticles for N-Alkylation Reactions: A New Concept for Catalysis
Sarno, Maria,Cirillo, Claudia,Iuliano, Mariagrazia
, (2019)
The catalytic activity of snowman-like and core-shell Fe3O4/Au nanoparticles (NPs), obtained through a “wet chemistry” approach which directly restitutes nanocatalysts stable and highly active in the reaction medium, was tested towards N-alkylation reactions. The nanocatalysts were tested for the synthesis of secondary amines. The core-shell NPs, thanks to the surface properties, homogeneous dispersion and intimate connection with reagents in the catalyst medium, exhibited an excellent catalytic activity (e. g. >99 % yield and conversion of aniline in very short time and mild conditions). Owing to the magnetic part, the nanoparticles can be easily separated and reused, showing an almost stable activity after 10 cycles.
Easy and One-Step Synthesis of Ir Single Atom Doped PPy Nanoparticles for Highly Active N-Alkylation Reaction
Iuliano, Mariagrazia,Sarno, Maria,Cirillo, Claudia,Ponticorvo, Eleonora,De Pasquale, Salvatore
, p. 644 - 653 (2021)
Single atoms are nowadays considered new catalysts offering a lot of advantages such as reduced cost and use of noble metals. Here, we report the catalytic activity towards N-alkylation reactions of single atoms (SACs) of iridium doped polypyrrole (Ir?PPy nanoparticles). The new nanocatalyst exhibits excellent behavior due to the combination of highly active SACs catalyst and the organic conductive support providing strong binding of single atoms and thus improved reusability and easiness to handle. In the presence of a low amount of Ir and of a suitable base, excellent activity (yield >99 %) and selectivity (>99 %) were obtained. In the optimized Ir condition (3 wt.% of Ir) an aniline conversion of about 99 %, with excellent selectivity, just after 600 min, was obtained. Recyclability tests show that the catalyst can be successfully recycled six times without significant catalyst activity loss.
Highly selective direct amination of primary alcohols over a Pd/K-OMS-2 catalyst
Ousmane,Perrussel,Yan,Clacens,De Campo,Pera-Titus
, p. 439 - 452 (2014)
A new Pd-substituted octahedral molecular sieve (Pd/K-OMS-2) catalyst has been prepared for the direct amination of alcohols with primary amines operating under the borrowing hydrogen mechanism. The catalyst offered full conversion and high selectivity toward N-benzylaniline in the model alkylation reaction of aniline with benzyl alcohol at mild temperature (160 C) for 3 h with neither production of the tertiary amine nor toluene. Pd/K-OMS-2 performed as a tandem tri-functional catalyst, first oxidizing benzyl alcohol to benzaldehyde, behaving as a Lewis acid for imine formation, and finally reducing the imine to the secondary amine. The catalyst was characterized in depth using BET, XRD, H2-TPR, XPS, FTIR, TEM, TGA/DTG, and ICP-AES / EDX to elucidate the nature of the active sites. The unexpectedly high performance of the Pd/K-OMS-2 catalyst can be ascribed, at least partially, to the in situ generation of a very active, selective and partially recyclable Pd-substituted/supported hausmannite phase (i.e., Pd/Mn3O4) in the early stage of the reaction with a high density of surface oxygen moieties. We argue about a possible role of a Pd(IV)/Pd(II) redox pump for exchanging hydrogen during the amination reaction.
Ruthenium Azocarboxamide Half-Sandwich Complexes: Influence of the Coordination Mode on the Electronic Structure and Activity in Base-Free Transfer Hydrogenation Catalysis
Sommer, Michael G.,Marinova, Sofiya,Krafft, Michael J.,Urankar, Damijana,Schweinfurth, David,Bubrin, Martina,Ko?mrlj, Janez,Sarkar, Biprajit
, p. 2840 - 2849 (2016)
Azocarboxamides were used as chelating ligands in ruthenium half-sandwich complexes. The synthesis and characterization of two new complexes with an unprecedented coordination motif are presented together with an in-depth investigation of two recently published complexes. Three different coordination modes of the ligands were realized, as evident by NMR spectroscopy and single-crystal X-ray diffraction. The use of base during the synthesis leads to a coordination of a deprotonated ligand, while the introduction of additional donor atoms results in a noncoordinated amide group. The first systematic experimental (cyclic voltammetry and UV-vis-NIR and EPR spectroelectrochemistry) and theoretical (DFT) investigation of the electronic structure of metal complexes bearing this redox-active ligand class is presented, revealing redox processes with ligand contribution. The absorption spectra and electrochemistry are mainly determined by the protonation state of the ligand. While complexes 2[PF6], 3[PF6], and 4[PF6] with neutral azocarboxamides show similar electronic spectra and cyclovoltammograms, the incorporation of a deprotonated monoanionic ligand in complex 1 leads to significant changes of these properties. In contrast, the catalytic activity in the base-free transfer hydrogenation reaction is mainly dependent on the coordination of the amide group, with only minor effects of the protonation state. While complexes 3[PF6] and 4[PF6], with an uncoordinated amide group, are inactive without the addition of base, complexes 1 and 2[PF6], with a metal-bound amide group, show activity under base-free conditions. The impact of the position of the amide group together with the detection of metal hydride species in 1H NMR spectroscopy suggests the operation of metal-ligand bifunctional catalysis to take place when no base is added.
Synthesis and characterization of hierarchical ZSM-5 zeolite containing Ni nanoparticles for one-pot reductive amination of aldehydes with nitroarenes
Kalbasi, Roozbeh Javad,Mazaheri, Omid
, p. 86 - 91 (2015)
In this paper, we wish to report the synthesis and characterization of nickel nanoparticles supported on acidic form of ZSM-5 zeolite (Ni/H-mZSM-5) with microporous/mesoporous hierarchical structure. This catalyst was effectively employed as novel acid-metal bi-functional heterogeneous catalyst for direct one-pot reductive amination of aldehydes with nitroarenes in the presence of NaBH4 as a mild reducing agent. Excellent yields at room temperature and short reaction time in aqueous media conditions were obtained.
Sublimation-Induced Sulfur Vacancies in MoS2 Catalyst for One-Pot Synthesis of Secondary Amines
Zhang, Yunrui,Gao, Yongjun,Yao, Siyu,Li, Siwei,Asakura, Hiroyuki,Teramura, Kentaro,Wang, Haijun,Ma, Ding
, p. 7967 - 7975 (2019)
MoS2 catalysts with abundant S and Mo defects have been developed for the one-pot reductive amination of nitro compounds with aldehydes to synthesize secondary amines. The combination of multiple structural characterizations demonstrates that the density of S vacancies can be tuned by changing the thermal sublimation temperature. The experimental results and DFT calculations demonstrate that S vacancies on the surface of MoS2 are the active sites for the hydrogenation of the intermediate imines to the final products secondary amines.
Heterogeneous Catalytic Transfer Partial-Hydrogenation with Formic Acid as Hydrogen Source Over the Schiff-Base Modified Gold Nano-Catalyst
Wang, Xinkui,Qiu, Zhen,Liu, Qinggang,Chen, Xiao,Tao, Shengyang,Shi, Chuan,Pang, Min,Liang, Changhai
, p. 517 - 524 (2017)
Abstract: The catalytic hydrogenation transformation with gaseous hydrogen in liquid phase always refers to a harsh condition and over-hydrogenation, and it is highly desired to develop new methods with partial-hydrogenation at mild condition. Herein, a heterogeneous catalytic transfer partial-hydrogenation strategy with formic acid as hydrogen source was developed over the Schiff-base modified gold nano-catalysts. The Au/Schiff-SiO2catalyst was successfully prepared by one pot aldimine condensation and NaBH4reduction of a gold precursor. The characterization results indicated that the gold nanoparticles with an average size below 2?nm were highly dispersed over the Schiff-base modified silica support. Such Schiff-based gold nano-catalysts exhibits excellent activity and partial-hydrogenation selectivity, with a high yield (>99%) for phenylacetylene partial-hydrogenation and achieving a 75% chemoselectivity for imines at a relative low temperature and atmospheric pressure. More importantly, the excess of formic acid can be removed by the direct dissociation of formic acid over Au/Schiff-SiO2catalyst with CO2emission into atmosphere, which leads to a hydrogen source as clean as hydrogen gaseous, but with a much more high activity and selectivity under mild reaction process. Graphical Abstract: [Figure not available: see fulltext.]
A microwave-assisted SmI2-catalyzed direct N-alkylation of anilines with alcohols
Gour, Jitendra,Gatadi, Srikanth,Malasala, Satyaveni,Yaddanpudi, Madhavi Venkata,Nanduri, Srinivas
, p. 7488 - 7494 (2019)
A new protocol for the alkylation of aromatic amines has been described using alcohols in the presence of SmI2 as a catalyst with the generation of water as the sole byproduct. The reaction proceeds under MW conditions and selectively generates monoalkylated amines. This protocol features a broad substrate scope and good functional-group tolerance with moderate to high yields.
First used of Alkylbenzimidazole-Cobalt(II) complexes as a catalyst for the N-Alkylation of amines with alcohols under solvent-free medium
?zdemir, ?smail,?zdemir, Nam?k,?ahin, Neslihan,Gürbüz, Nevin,Y?ld?r?m, ?lkay
, (2020)
In this study, alkylbenzimidazole-cobalt(II)-catalyzed direct N-alkylation reactions of amines with alcohols derivatives have been investigated under solvent-free medium. For this purpose, a series of cobalt(II) complexes bearing N-alkylbenzimidazole complexes have been synthesized and novel complexes fully characterized by elemental analysis, FT-IR, 1H NMR and, 13C{1H} NMR spectroscopies. Also, the structure of the complex 2a has been confirmed by X-ray crystallography. Generally, the N-alkylating reaction is usually performed in toluene with various metal complexes including cobalt. In this catalytic study of complexes, 2a-c has carried out in without solvent and alcohol acted both as solvent and reactant. Conversion and selectivity of amine products according to imine products for alkylation reactions have been seen high yield in medium solvent-free relative to in toluene.
Clay encapsulated ZnO nanoparticles as efficient catalysts for N-benzylation of amines
Dhakshinamoorthy, Amarajothi,Visuvamithiran, Pitchai,Tharmaraj, Vairaperumal,Pitchumani, Kasi
, p. 15 - 19 (2011)
ZnO nanoparticles encapsulated in K10-clay (K10-ZnO) are synthesised and characterised by UV-DRS, Emission spectra, powder XRD, SEM and HRTEM analyses. The constrained space and also the polar active sites in the clay support stabilise zinc oxide nanoparticles by preventing that aggregation and consequently no extra-capping agent is required. The synthesised ZnO nanoparticles are used for the efficient N-benzylation of anilines and the reusability of the catalyst is also studied. A suitable mechanism is proposed for this transformation.
Grouping Effect of Single Nickel?N4 Sites in Nitrogen-Doped Carbon Boosts Hydrogen Transfer Coupling of Alcohols and Amines
Su, Hui,Gao, Peng,Wang, Meng-Ying,Zhai, Guang-Yao,Zhang, Jun-Jun,Zhao, Tian-Jian,Su, Juan,Antonietti, Markus,Li, Xin-Hao,Chen, Jie-Sheng
, p. 15194 - 15198 (2018)
As a new type of heterogeneous catalyst with “homogeneous-like” activity, single-site transition-metal materials are usually treated as integrated but separate active centers. A novel grouping effect is reported for single Ni?N4 sites in nitrogen-doped carbon (Ni/NC), where an effective ligand-stabilized polycondensation method endows Ni/NC nanocatalysts with a high content of single-site Ni up to 9.5 wt %. The enhanced electron density at each single Ni?N4 site promotes a highly efficient hydrogen transfer, which is exemplified by the coupling of benzyl alcohol and aniline into N-benzylaniline with a turnover frequency (TOF) value of 7.0 molN-benzylaniline molmetal?1 h?1; this TOF outpaces that of reported stable non-noble-metal-based catalysts by a factor of 2.
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Traube,W.,v.Wedelstaedt
, p. 1384 (1900)
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Expanding the Scope of Chelating Triazolylidenes: Mesoionic Carbenes from the 1,5-“Click”-Regioisomer and Catalytic Synthesis of Secondary Amines from Nitroarenes
Suntrup, Lisa,Hohloch, Stephan,Sarkar, Biprajit
, p. 18009 - 18018 (2016)
Chelating 1,2,3-triazolylidenes have been established as privileged ligands in homogeneous catalysis. We present herein a new approach towards chelating 1,2,3-triazolylidene ligands based on the 1,5-regioisomer of the corresponding triazole, which can be obtained through simple click chemistry. The new ligands are compared to their 1,4-regioisomeric counterparts through coordination to the ruthenium p-cymene fragment. The complexes are characterized structurally and spectroscopically and are employed as (pre)catalysts in the reductive condensation of nitroarenes and primary alcohols to yield secondary amines. The activity of chelating mesoionic carbene ligands obtained from the two different regioisomers of the triazoles are compared and contrasted in catalysis. The performance of the ruthenium complexes with mesoionic carbenes could be improved through the choice of the employed base and reaction conditions, giving rise to the most effective systems thus far. The results presented here prove the utility of chelating mesoionic carbenes as an extremely potent class of ligands for the synthesis of secondary amines from nitroarenes.
Porous aromatic frameworks (PAFs) as efficient supports for N-heterocyclic carbene catalysts
Rangel-Rangel, Elizabeth,Verde-Sesto, Ester,Rasero-Almansa, Antonia M.,Iglesias, Marta,Sánchez, Félix
, p. 6037 - 6045 (2016)
Porous polymeric aromatic frameworks (PAFs) have high porosity and surface area, as well as high physicochemical stability; such characteristics are important in the design of heterogeneous catalysts with high catalytic efficiency and recyclability. This paper presents the synthesis, characterization, post-functionalization and catalytic performance of the resulting modified PAFs based on tetraphenyladamantane (PAFAd), tetraphenylmethane (PAFC) and 9,9′-spirobisfluorene (PAFspf) nodes. The PAFs were obtained by the Suzuki-Miyaura cross-coupling under microwave heating, and were sequentially reacted with 1-(chloromethoxy)octane and 1-mesityl-1H-imidazole or 2-(1H-imidazol-1-yl)pyridine to yield the corresponding imidazolium chloride derivative (PAF-Im) which readily formed stable N-heterocyclic carbene (NHC) iridium and ruthenium complexes (PAF-(NHC)Ir, PAF-(NHC)Ru). The materials were characterized by solid-state NMR spectroscopy, FTIR spectroscopy, and textural analysis. The PAF-(NHC)M materials display excellent catalytic performance in the N-alkylation of amines with alcohols and transfer hydrogenation of ketones over multiple catalytic cycles.
The synthesis of N-arylated amides via copper(II) triflate-catalyzed direct oxygenation and N-arylation of benzylamines with aryl iodides
Xu, Mei,Zhang, Xiao-Hong,Shao, Yin-Lin,Han, Jiang-Sheng,Zhong, Ping
, p. 2665 - 2670,6 (2012)
An efficient approach for the synthesis of N-arylated amides by copper(II) triflate-catalyzed direct oxygenation and N-arylation reaction of benzylamines with aryl iodides is reported. Various benzylamines and aryl iodides can participate in the reaction, providing a series of N-arylated amides in moderate to good yields.
Iron-catalyzed N-alkylation of aromatic amines via borrowing hydrogen strategy
Chen, Hui,Wang, Qingfu,Liu, Tingting,Chen, Haitao,Zhou, Duo,Qu, Fengbo
, p. 877 - 884 (2021)
Earth-abundant transition metals could be used as a noble metal replacement in catalysis not only for different catalytic reactivity but environmentally benign methodology. We report here on the iron-catalyzed synthesis of N-alkylated amines via borrowing hydrogen strategy and differently functionalized aniline derivatives are alkylated in good yields.
Influence of guanidinium salts and other ionic liquids on the three-component Aza-Diels-alder reaction
Mert-Balci, Fadime,Imrich, Hans-Georg,Conrad, Juergen,Beifuss, Uwe
, p. 1681 - 1692 (2013)
The three-component reaction of aniline, benzaldehyde, and dienophiles such as 2,3-dihydrofuran, ethyl vinyl ether, 2,3-dihydropyran, and cyclopentadiene can be promoted by ionic liquids like imidazolium salts and guanidinium salts under thermal as well a
One-pot synthesis of aniline N-alkylation from benzyl alcohol over Cu-Fe catalyst
Hara, Takayoshi,Ichikuni, Nobuyuki,Putro, Wahyu S.,Shimazu, Shogo
, (2020)
Cu-Fe catalysts prepared from layered double hydroxide (LDH) precursors were applied for the straightforward N-alkylation of aniline with benzyl alcohol in base- and oxidant-free conditions. Among the bimetallic Cu-M catalysts prepared from LDH precursors
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Murahashi et al.
, p. 931 (1974)
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BF3·Et2O as a metal-free catalyst for direct reductive amination of aldehydes with amines using formic acid as a reductant
Fan, Qing-Hua,Liu, Xintong,Luo, Zhenli,Pan, Yixiao,Xu, Lijin,Yang, Ji,Yao, Zhen,Zhang, Xin
supporting information, p. 5205 - 5211 (2021/07/29)
A versatile metal- and base-free direct reductive amination of aldehydes with amines using formic acid as a reductant under the catalysis of inexpensive BF3·Et2O has been developed. A wide range of primary and secondary amines and diversely substituted aldehydes are compatible with this transformation, allowing facile access to various secondary and tertiary amines in high yields with wide functional group tolerance. Moreover, the method is convenient for the late-stage functionalization of bioactive compounds and preparation of commercialized drug molecules and biologically relevant N-heterocycles. The procedure has the advantages of simple operation and workup and easy scale-up, and does not require dry conditions, an inert atmosphere or a water scavenger. Mechanistic studies reveal the involvement of imine activation by BF3and hydride transfer from formic acid.
Nickel Complexes Bearing N,N,O-Tridentate Salicylaldiminato Ligand: Efficient Catalysts for Imines Formation via Dehydrogenative Coupling of Primary Alcohols with Amines
Han, Zhangang,Hao, Zhiqiang,Lin, Jin,Lu, Guo-Liang,Zhang, Junhua,Zhang, Xiaoying
, p. 3843 - 3853 (2021/11/18)
Treatment of salicylaldiminato ligand L1H-L2H (L1H = 2,4-di-tert-butyl-6-((quinolin-8-ylimino)methyl)phenol; L2H = 2,4-di-tert-butyl-6-(((2-(diethylamino)ethyl)imino)methyl)phenol) with Ni(OAc)2·4H2O in refluxing ethanol afforded nickel complexes [(L1)Ni(OAc)] (1) and [(L2)Ni(OAc)] (2), respectively. Reaction of L3H (L3H = (2,4-di-tert-butyl-6-(((2-(pyridin-2-yl)ethyl)imino)methyl)phenol)) with Ni(OAc)2·4H2O in the presence of excess triethylanmine gave the dual ligands coordinated nickel complex [(L2)2Ni] (3). Complexes 1-3 were well characterized by high-resolution mass spectrometry, infrared spectroscopy, elemental analysis, and X-ray diffraction analysis. All the three Ni(II) complexes exhibited efficient activity and good selectivity in the acceptorless dehydrogenative coupling of alcohols and amines to produce imines and diimines. The present protocol provides an atom-economical and sustainable route for the synthesis of various imine derivatives by employing an earth-abundant nickel salt and easily prepared salicylaldiminato ligands.
Synthesis of an Fe-Pd bimetallic catalyst for: N -alkylation of amines with alcohols via a hydrogen auto-transfer methodology
Wu, Peng-Yu,Lu, Guo-Ping,Cai, Chun
, p. 396 - 404 (2021/01/28)
Hydrogen auto-transfer (HAT) or borrowing hydrogen (BH) methodology which combines dehydrogenation, intermediate reaction and hydrogenation, is recognized as an excellent strategy for one-pot synthesis from an economic and environmental point of view. Although much effort has been made on the development of catalysts for HAT reactions, harsh conditions, external base or large amounts of noble metals are still required in most reported catalysis systems, and thus the exploration of a highly efficient and recyclable heterogeneous catalyst remains meaningful. In this work, a novel bimetallic catalyst, Fe10Pd1/NC500 derived from bimetallic MOF NH2-MIL-101(Fe10Pd1), has been prepared, and the catalyst exhibits superior catalytic performance for the N-alkylation of amines with alcohols via a hydrogen auto-transfer methodology. High yields of the desired products were achieved at 120 °C with an alcohol/amine molar ratio of 2?:?1 and required no external additive or solvent. A distinct enhancement in catalytic performance is observed when compared with monometallic catalysts, which can be ascribed to the "synergistic effects"inside the bimetallic alloys. The N-doped carbon support has been revealed to provide the necessary basicity which avoids the requirement of an external base. Moreover, a wide substrate range and remarkable reusability have been shown by Fe10Pd1/NC500, and this work highlights new possibilities for bimetallic catalysts applied in sustainable chemistry.
