cas 98-16-8, 3-Aminobenzotrifluoride | Articles data

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Hydroboration reduction reaction of aromatic nitro compounds without transition metal catalysis
The invention relates to a hydroboration reduction reaction of aromatic nitro compounds without transition metal catalysis. According to the method, triethyl boron and potassium tert-butoxide are used as catalysts for the first time, and an aromatic nitro compound and pinacol borane which is low in price and easy to obtain can be conveniently catalyzed to be subjected to a hydroboration reduction reaction under mild conditions to prepare aromatic amine products. Compared with a traditional method, the method generally has the advantages that the catalyst is cheap and easy to obtain, operation is convenient, and reaction is safe. The selective hydroboration reduction reaction of the non-transition metal reagent catalyzed aromatic nitro compound and pinacol borane is realized for the first time, and a practical new reaction strategy is provided for laboratory preparation or industrial production of aromatic amine products.
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Paragraph 0006; 0025-0028

(2021/07/31)

Chemoselective Hydrogenation of Nitroarenes Using an Air-Stable Base-Metal Catalyst
The reduction of nitroarenes to anilines as well as azobenzenes to hydrazobenzenes using a single base-metal catalyst is reported. The hydrogenation reactions are performed with an air-and moisture-stable manganese catalyst and proceed under relatively mild reaction conditions. The transformation tolerates a broad range of functional groups, affording aniline derivatives and hydrazobenzenes in high yields. Mechanistic studies suggest that the reaction proceeds via a bifunctional activation involving metal-ligand cooperative catalysis.
Zubar, Viktoriia,Dewanji, Abhishek,Rueping, Magnus
supporting information
p. 2742 - 2747
(2021/05/05)

A Concise Route to Cyclic Amines from Nitroarenes and Ketoacids under Iron-Catalyzed Hydrosilylation Conditions
Starting from nitroarenes, under hydrosilylation conditions, using a well-defined N-heterocyclic carbene iron(0) catalyst, (IMes)Fe(CO)4, the corresponding aniline derivatives were produced in 61–92% isolated yields. More impressively, a selective synthesis of cyclic amines such as pyrrolidines, piperidines and azepanes were conducted from levulinic acid, 1,5- and 1,6-keto acids, respectively. The sequential procedure proceeded under both visible light irradiation and thermal conditions with 20 examples in isolated yields up to 69%. (Figure presented.).
Ammaiyappan, Yuvaraj,Darcel, Christophe,Tongdee, Satawat,Wu, Jiajun
p. 3859 - 3865
(2021/07/12)

Efficient hydrogenation catalyst designing via preferential adsorption sites construction towards active copper
Based on the experimental and DFT calculation results, here for the first time we built preferential adsorption sites for nitroarenes by modification of the supported Cu catalysts surface with 1,10-phenathroline (1,10-phen), by which the yield of aniline via reduction of nitroarene is enhanced three times. Moreover, a macromolecular layer was in-situ generated on supported Cu catalysts to form a stable macromolecule modified supported Cu catalyst, i.e., CuAlOx-M. By applying the CuAlOx-M, a wide variety of nitroarene substrates react smoothly to afford the desired products in up to > 99% yield with > 99% selectivity. The method tolerates a variety of functional groups, including halides, ketone, amide, and C = C bond moieties. The excellent catalytic performance of the CuAlOx-M can be attributed to that the 1,10-phen modification benefits the preferential adsorption of nitrobenzene and slightly weakens adsorption of aniline on the supported nano-Cu surface.
Dai, Xingchao,He, Dongcheng,Li, Teng,Shi, Feng,Wang, Hongli,Wang, Tao,Wang, Xinzhi
p. 397 - 406
(2021/07/21)

Unlocking Amides through Selective C–N Bond Cleavage: Allyl Bromide-Mediated Divergent Synthesis of Nitrogen-Containing Functional Groups
We report a new set of reactions based on the unlocking of amides through simple treatment with allyl bromide, creating a common platform for accessing a diverse range of nitrogen-containing functional groups such as primary amides, sulfonamides, primary amines, N-acyl compounds (esters, thioesters, amides), and N-sulfonyl esters. The method has potential industrial applicability, as demonstrated through gram-scale syntheses in batch and in a continuous flow system.
Govindan, Karthick,Chen, Nian-Qi,Chuang, Yu-Wei,Lin, Wei-Yu
supporting information
p. 9419 - 9424
(2021/11/30)

Cu-Catalyzed Cross-Coupling of Nitroarenes with Aryl Boronic Acids to Construct Diarylamines
The development and study of a simple copper-catalyzed reaction of nitroarenes with aryl boronic acids to form diarylamines that uses phenyl silane as the stoichiometric terminal reductant is described. This cross-coupling reaction requires as little as 2 mol % of CuX and 4 mol % of diphosphine for success and tolerates a broad range of functional groups on either the nitroarene or the aryl boronic acid to afford the amine in good yield. Mechanistic investigations established that the cross-coupling reaction proceeds via a nitrosoarene intermediate and that copper is required to catalyze both the deoxygenation of the nitroarene to afford the nitrosoarene and C-NAr bond formation of the nitrosoarene with the aryl boronic acid.
Guan, Xinyu,Zhu, Haoran,Driver, Tom G.
p. 12417 - 12422
(2021/10/12)

Palladium Supported on Carbon Nanoglobules as a Promising Catalyst for Selective Hydrogenation of Nitroarenes
The catalysts 1?wt% palladium supported on carbon nanoglobules (CNGs) were shown to be highly active in the liquid-phase hydrogenation of various nitroarenes and provided nearly 100% selectivity to aromatic amines at complete conversion under mild conditions (323?K, 0.5?MPa, 1?h). The catalytic activity (in terms of turnover frequency and substrate conversion) and selectivity depend on the kind of CNGs support, catalyst preparation method and the reaction conditions (solvent nature). The Pd/CNGs catalyst can be repeatedly used while maintaining the same catalytic performance. The excellent performances of Pd/CNGs catalysts can be due to the globular morphology of the supports as well as the absence of micropores and pronounced surface defects. Graphic Abstract: [Figure not available: see fulltext.]
Mironenko,Belskaya,Stepanova,Gulyaeva,Trenikhin,Likholobov
p. 888 - 900
(2019/11/11)

One-Pot Generation of Benzynes from Phenols: Formation of Primary Anilines by the Deoxyamination of Phenols
Benzynes were selectively generated in situ from phenols and trapped regioselectively with potassium hexamethyldisilazide to form primary anilines following acidic workup. The direct conversion of a phenolic hydroxyl group into a free amino group is a useful method for the preparation of primary aryl amines that are hard to synthesize by using coupling reactions involving phenol derivatives with ammonia. Whereas reactions of ortho- and meta-substituted phenols produced meta-substituted anilines exclusively, those of para-substituted phenols provided ortho-silylanilines.
Akai, Shuji,Ikawa, Takashi,Masuda, Shigeaki
(2020/03/23)

EffectiveN-methylation of nitroarenes with methanol catalyzed by a functionalized NHC-based iridium catalyst: a green approach toN-methyl amines
Compound [IrBr(CO)2(κC-tBuImCH2PyCH2OMe)] featuring a flexible pyridine/OMe functionalized NHC ligand κ1C coordinated efficiently catalyzes the selectiveN-monomethylation of nitroarenes using methanol as both the reducing agent and the C1 source. A range of functionalized nitroarenes including heterocyclic or sterically hindered derivatives have been efficiently converted to the correspondingN-monomethyl amines in good yields at low catalyst loadings using sub-stoichiometric amounts of Cs2CO3as a base. Mechanistic investigations support a borrowing-hydrogen mechanism in which methanol acts as the hydrogen source and methylating agent. Further, the hydrogen transfer reduction of nitrobenzene to aniline under optimized reaction conditions should proceed through a direct mechanism involving nitrosobenzene andN-phenylhydroxylamine intermediates.
González-Lainez, Miguel,Jiménez, M. Victoria,Passarelli, Vincenzo,Pérez-Torrente, Jesús J.
p. 3458 - 3467
(2020/06/17)

Discovery and characterization of an acridine radical photoreductant
Photoinduced electron transfer (PET) is a phenomenon whereby the absorption of light by a chemical species provides an energetic driving force for an electron-transfer reaction1–4. This mechanism is relevant in many areas of chemistry, including the study of natural and artificial photosynthesis, photovoltaics and photosensitive materials. In recent years, research in the area of photoredox catalysis has enabled the use of PET for the catalytic generation of both neutral and charged organic free-radical species. These technologies have enabled previously inaccessible chemical transformations and have been widely used in both academic and industrial settings. Such reactions are often catalysed by visible-light-absorbing organic molecules or transition-metal complexes of ruthenium, iridium, chromium or copper5,6. Although various closed-shell organic molecules have been shown to behave as competent electron-transfer catalysts in photoredox reactions, there are only limited reports of PET reactions involving neutral organic radicals as excited-state donors or acceptors. This is unsurprising because the lifetimes of doublet excited states of neutral organic radicals are typically several orders of magnitude shorter than the singlet lifetimes of known transition-metal photoredox catalysts7–11. Here we document the discovery, characterization and reactivity of a neutral acridine radical with a maximum excited-state oxidation potential of ?3.36 volts versus a saturated calomel electrode, which is similarly reducing to elemental lithium, making this radical one of the most potent chemical reductants reported12. Spectroscopic, computational and chemical studies indicate that the formation of a twisted intramolecular charge-transfer species enables the population of higher-energy doublet excited states, leading to the observed potent photoreducing behaviour. We demonstrate that this catalytically generated PET catalyst facilitates several chemical reactions that typically require alkali metal reductants and can be used in other organic transformations that require dissolving metal reductants.
MacKenzie, Ian A.,Wang, Leifeng,Onuska, Nicholas P. R.,Williams, Olivia F.,Begam, Khadiza,Moran, Andrew M.,Dunietz, Barry D.,Nicewicz, David A.
p. 76 - 80
(2020/04/17)

Synthesis, molecular docking studies, and larvicidal activity evaluation of new fluorinated neonicotinoids against Anopheles darlingi larvae
Anopheles darlingi is the main vector of malaria in Brazil, characterized by a high level of anthropophilia and endophagy. Imidacloprid, thiacloprid, and acetamiprid are the most widespread insecticides of the neonicotinoid group. However, they produce adverse effects on the non-target insects. Flupyradifurone has been marketed as an alternative to non-fluorinated neonicotinoids. Neonicotinoids containing trifluoroacethyl substituent reveal increased insecticidal activity due to higher hydrophobicity and metabolic stability. We synthesized novel neonicotinoid insecticides containing fluorinated acceptor groups and their interactions were estimated with the nicotinic acetylcholine receptor (nAChR) binding site by molecular docking studies, to evaluate their larvicidal activity against A. darlingi, and to assess their outdoor photodegradation behavior. New neonicotinoid analogues were prepared and characterized by NMR and mass-spectrometry. The synthesized molecules were modelled by time-dependent density functional theory and analyzed, their interaction with nAChR was investigated by molecular docking. Their insecticide activity was tested on Anopheles larvae collected in suburban area of Manaus, Brazil. Four new fluorinated neonicotinoid analogs were prepared and tested against 3rd instars larvae of A. darlingi showing high larvicidal activity. Docking studies reveal binding modes of the synthesized compounds and suggest that their insecticidal potency is governed by specific interactions with the receptor binding site and enhanced lipophilicity. 2-Chloro-5-(2-trifluoromethyl-pyrrolidin-1-ylmethyl)pyridine 5 showed fast degradation in water maintaining high larvicidal activity. All obtained substances possessed high larvicidal activity in low concentrations in 48 hours of exposure, compared to commercial flupyradifurone. Such activity is connected to a unique binding pattern of the synthesized compounds to insect's nAChR and to their enhanced bioavailability owing to introduction of fluorinated amino-moieties. Therefore, the compounds in question have a high potential for application as control agents for insects transmitting tropical diseases, and they will be less persistent in the environment.
da Silva Mesquita, Rochelly,Kyrylchuk, Andrii,Grafova, Iryna,Kliukovskyi, Denys,Bezdudnyy, Andriy,Rozhenko, Alexander,Tadei, Wanderli Pedro,Leskel?, Markku,Grafov, Andriy
(2020/02/13)

o-aminotrifluorotoluene synthesis method
The invention discloses an o-aminotrifluorotoluene synthesis method, wherein trifluorotoluene is used as a raw material, and a target compound is obtained through two-step reaction of nitration and reduction. Compared with the method in the prior art, the method of the invention has the following characteristics that trifluorotoluene is used as the raw material, so that the source is wide, and thepreparation is convenient; the nitration reaction is carried out at a normal pressure and a low temperature, so that the corrosion of the material to the pipeline and the equipment is small, and thenitration reaction is safe and reliable to the environment and operators; and the cheap nickel catalyst is used for replacing the common noble metal catalysts such as palladium, platinum and the like,so that the production cost is reduced, the methanol as the solvent is convenient to recover and can be recycled, and the emission of organic matters in the production process is reduced.
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Paragraph 0006; 0013-0021

(2020/01/25)

Superior activity and selectivity of heterogenized cobalt catalysts for hydrogenation of nitroarenes
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).
Li, Wu,Artz, Jens,Broicher, Cornelia,Junge, Kathrin,Hartmann, Heinrich,Besmehn, Astrid,Palkovits, Regina,Beller, Matthias
p. 157 - 162
(2019/01/10)

Metal-free chemoselective reduction of nitroaromatics to anilines via hydrogen transfer strategy
A novel protocol for chemoselective reduction of aromatic nitro compounds to aromatic amines has been established. The metal-free reduction goes through a hydrogen transfer process. Various easily reducible functional groups can be well tolerated under the optimized reaction conditions.
Shuai, Qi,Li, Jun,Zhao, Feng,Su, Weike,Deng, Guojun
p. 965 - 975
(2019/04/13)

Copper(ii)-catalyzed c-n coupling of aryl halides and n-nucleophiles promoted by quebrachitol or diethylene glycol
Herein, we report the natural ligand quebrachitol (QCT) as a promoter for a Cu(II) catalyst, which is highly effective for N-Arylation of various amines and related aryl halides. A series of diarylamine derivatives were obtained in high yields by using diethylene glycol (DEG) as both ligand and solvent. The C-N coupling reactions proceed under mild conditions and exhibit good functional group tolerance.
Chen, Guoliang,Chen, Yuanguang,Du, Fangyu,Fu, Yang,Wu, Ying,Zhou, Qifan
supporting information
p. 2161 - 2168
(2019/11/25)

NITROGEN-CONTAINING BIOPOLYMER-BASED CATALYSTS, THEIR PREPARATION AND USES IN HYDROGENATION PROCESSES, REDUCTIVE DEHALOGENATION AND OXIDATION
The present invention relates to a process for the preparation of a nitrogen containing biopolymer-based catalyst by pyrolysis of a metal complex with a nitrogen-containing biopolymer and to the nitrogen containing biopolymer-based catalysts obtainable by this process. In particular, the invention relates to a nitrogen containing biopolymer-based catalyst comprising metal particles and at least one nitrogen containing carbon layer. The invention also relates to the use of a nitrogen containing biopolymer-based catalyst in a hydrogenation process, preferably in a process for hydrogenation of nitroarenes, nitriles or imines; in a reductive dehalogenation process of C-X bonds, wherein X is CI, Br or I, preferably in a process for dehalogenation of organohalides or in a process for deuterium labelling of arenes via dehalogenation of organohalides; or in an oxidation process. Further, the invention relates to a metal complex with the nitrogen containing biopolymer, wherein the metal is a transition metal selected from the group consisting of manganese, ruthenium, cobalt, rhodium, nickel, palladium and platinum, preferably cobalt or nickel, and wherein the nitrogen containing biopolymer is selected from chitosan, chitin and a polyamino acid, preferably chitosan or chitin.
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Page/Page column 31-32

(2018/07/29)

A pharmaceutical intermediate between the synthesis of trifluoromethyl aniline (by machine translation)
The present invention discloses a pharmaceutical intermediate between the synthesis of trifluoromethyl aniline, nitro-trifluoro-toluene, ethanol, hydrazine hydrate, 3 - chloro-propyl triethoxy silane, anhydrous toluene, SiO2 , Imidazole and potassium iodide as the main raw material, the linkage law in the cation of the ionic liquid is introduced to functional group, with a reactive functional group on the carrier and produce the chemical bond, thereby realizing the cation of the ionic liquid catalyst is solid, its the used raw materials according to the following proportion: between nitro-benzotrifluoride, hydrazine hydrate molar ratio of 1:3; N - 3 - chloro-propyl triethoxy silane, SiO2 The mass ratio of 1:1; imidazole, potassium iodide and the mass ratio of 6:1; in three fluorine methylaniline synthesis process is simple, the cost of the catalyst is relatively low, the serviceability is strong, compared with the traditional solid and liquid acid catalyst has greater potential for development and application value, the trifluoromethyl aniline synthesis reaction between the excellent catalytic effect. (by machine translation)
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Paragraph 0008; 0009; 0010-0029

(2018/06/16)

Application of Silicon-Initiated Water Splitting for the Reduction of Organic Substrates
The use of water as a donor for hydrogen suitable for the reduction of several important classes of organic compounds is described. It is found that the reductive water splitting can be promoted by several metalloids among which silicon shows the best efficiency. The developed methodologies were applied for the reduction of nitro compounds, N-oxides, sulfoxides, alkenes, alkynes, hydrodehalogenation as well as for the gram-scale synthesis of several substrates of industrial importance.
Gevorgyan, Ashot,Mkrtchyan, Satenik,Grigoryan, Tatevik,Iaroshenko, Viktor O.
p. 375 - 382
(2018/06/04)

Visible-Light-Driven Chemoselective Hydrogenation of Nitroarenes to Anilines in Water through Graphitic Carbon Nitride Metal-Free Photocatalysis
Green and efficient procedures are essential for the chemoselective hydrogenation of functionalized nitroarenes to form industrially important anilines. Herein, it is shown that visible-light-driven, chemoselective hydrogenation of functionalized nitroarenes with groups sensitive to forming anilines can be achieved in good to excellent yields (82–100 %) in water under relatively mild conditions and catalyzed by low-cost and recyclable graphitic carbon nitride. The process is also applicable to gram-scale reaction, with a yield of aniline of 86 %. A study of the mechanism reveals that visible-light-induced electrons are responsible for the hydrogenation reactions, and thermal energy can also promote the photocatalytic activity. A study of the kinetics shows that this reaction possibly occurs through one-step hydrogenation or stepwise condensation routes. A wide range of applications can be expected for this green, efficient, and highly selective photocatalysis system in reduction reactions for the synthesis of fine chemicals.
Xiao, Gang,Li, Peifeng,Zhao, Yilin,Xu, Shengnan,Su, Haijia
p. 1950 - 1955
(2018/07/31)

Chemoselective hydrogenation of nitroarenes catalyzed by cellulose-supported Pd NPs
Cellulose-supported palladium nanoparticles (NPs) were prepared by straightforward deposition of metal NPs on modified cellulose. The catalyst exhibited excellent catalytic activity and selectivity in room-temperature hydrogenation of various nitroarenes to arylamines under atmospheric hydrogen pressure in neat water without any additives. High chemoselectivity was also achieved in the hydrogenation of substituted nitroarenes with multiple reducible groups. The catalyst can be recycled by simple centrifugation and reused for at least 4 times without significant decline of yields.
Li, Dan-dan,Zhang, Jia-wei,Cai, Chun
p. 47 - 50
(2017/10/06)

Nitrogen-Doped Graphene-Supported Iron Catalyst for Highly Chemoselective Hydrogenation of Nitroarenes
A nitrogen-doped graphene-supported iron catalyst was used for the first time in the hydrogenation of a series of nitroarenes to give the corresponding amines with excellent activity and chemoselectivity under mild reaction conditions. Physicochemical characterization of the catalyst by transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and M?ssbauer spectroscopy revealed the formation of iron particles with an iron oxide core and a metallic iron shell that were coated by a few layers of nitrogen-doped graphene. The unique structure of FeNx/C in the catalyst was proven to contribute to the hydrogenation activity.
Wei, Zuojun,Hou, Yaxin,Zhu, Xinmiao,Guo, Liangyu,Liu, Yingxin,Zhang, Anyun
p. 2009 - 2013
(2018/03/21)

Heterogeneous Iron-Catalyzed Hydrogenation of Nitroarenes under Water-Gas Shift Reaction Conditions
Reduction of various nitroarenes in the presence of heterogeneous iron oxide-based catalyst Fe 2 O 3 /NGr@C under water-gas shift reaction (WGSR) conditions has been demonstrated. The catalytic material is prepared in a straightforward manner via deposition/pyrolysis of iron-phenanthroline complex on carbon support. It shows high chemoselectivity towards the reduction of nitroarenes in the presence of other reducible and/or poisoning-capable functional groups. Hydrogenation is achieved using CO/H 2 O as a hydrogen source. Furthermore, it is demonstrated that the presence of triethylamine additive has a significant positive effect on the rate of reduction.
Ryabchuk, Pavel,Junge, Kathrin,Beller, Matthias
supporting information
p. 4369 - 4376
(2018/11/21)

Aminobenzotrifluoride solvent-free hydrogenation reduction process
The invention relates to an aminobenzotrifluoride solvent-free hydrogenation reduction process and belongs to the field of pesticide chemical product preparation methods. The process mainly comprisesthe following steps: putting a raw material, namely nitryl benzotrifluoride, into a reaction kettle, performing a hydrogenation reduction reaction under conditions that no solvent is used and raney nickel is adopted as a catalyst, after the reaction is completed, cooling, filtering at normal pressure, recycling the catalyst, and performing negative pressure distillation on filtrate, thereby obtaining aminobenzotrifluoride. The whole process is carried out under a solvent-free process condition, so that emission of organic matters in the conventional production process is reduced; the consequence that a carbaryl byproduct is generated from reactions of solvents such as methanol with reduced amino is avoided, so that the product purity can be improved; compared with a conventional solvent method, the process is relatively low in temperature, relatively low in energy consumption, low in production cost and beneficial to energy conservation and emission reduction.
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Paragraph 0024; 0026; 0027; 0028; 0030; 0032

(2018/10/02)

O-aminotrifluorotoluene solvent-free hydrogenation reduction technology
The invention relates to an o-aminotrifluorotoluene solvent-free hydrogenation reduction technology belonging to the field of preparation methods of pesticide chemical products. The technology mainlycomprises the following steps: adding raw material nitryl trifluorotoluene into a reduction reaction kettle, carrying out hydrogenation reduction reaction under the conditions that no solvent is usedand raney nickel is taken as a catalyst, after the reaction is finished, cooling, filtering at normal pressure and recycling the catalyst, and carrying out negative pressure rectification on filtrate,so that o-aminotrifluorotoluene can be obtained. The whole process adopts the solvent-free technological condition, and discharge of organic matters in the traditional production process is reduced;the defect that solvents such as methanol react with reduced amino and carbaryl byproducts are generated is overcome, and product purity is improved; and compared with an existing solvent method, temperature is relatively low, energy consumption is relatively low, production cost is reduced, and energy conservation and discharge reduction are facilitated.
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Paragraph 0011; 0020-0025

(2018/09/11)

Method for processing fluoride ions in aminobenzotrifluoride
The invention discloses a method for processing fluoride ions in aminobenzotrifluoride. The method for processing the fluoride ions in the aminobenzotrifluoride comprises the following steps: taking trifluorotoluene as a raw material, and carrying out mixed acid nitration and catalyzed hydrogeneration reduction under normal pressure to synthesize the aminobenzotrifluoride, wherein a coarse product contains the fluoride ions; mixing and stirring the coarse product of the aminobenzotrifluoride and refined lime proportionally, combining the fluoride ions with calcium ions of calcium oxide to generate calcium fluoride CaF2, and filtering to remove precipitate to obtain trifluoromethylbenzene; drying the trifluoromethylbenzene without the fluoride ions to obtain the refined trifluoromethylbenzene, wherein the main ingredient in the refined lime is calcium oxide CaO. By the mode, the fluoride ions in the trifluoromethylbenzene can be removed effectively, after the fluoride ions are treated once, the content of the fluoride ions can be below 10 ppm generally, and after the fluoride ions are treated twice, the content of the fluoride ions can be below 5 ppm.
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Paragraph 0016

(2017/06/02)

Catalytic Reductions and Tandem Reactions of Nitro Compounds Using in Situ Prepared Nickel Boride Catalyst in Nanocellulose Solution
A mild and efficient method for the in situ reduction of a wide range of nitroarenes and aliphatic nitrocompounds to amines in excellent yields using nickel chloride/sodium borohydride in a solution of TEMPO-oxidized nanocellulose in water (0.01 wt %) is described. The nanocellulose has a stabilizing effect on the catalyst, which increases the turnover number and enables low loading of nickel catalyst (0.1-0.25 mol % NiCl2). In addition, two tandem protocols were developed in which the in situ formed amines were either Boc-protected to carbamates or further reacted with an epoxide to yield β-amino alcohols in excellent yields.
Prathap, Kaniraj Jeya,Wu, Qiong,Olsson, Richard T.,Dinér, Peter
supporting information
p. 4746 - 4749
(2017/09/23)

Preparation method of 3-hydroxyphenyl trifluoromethyl ether
The invention provides a preparation method of 3-hydroxyphenyl trifluoromethyl ether. The preparation method comprises the following steps: taking 4-trifluoromethoxyaniline as a raw material; and successively carrying out acetylation, nitrification, deacetylation, deaminizating, reduction and hydrolysis reaction on the 4-trifluoromethoxyaniline to obtain the 3-hydroxyphenyl trifluoromethyl ether. The preparation method is high in yield of products, simple to operate and low in production cost; and industrialization is facilitated.
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Paragraph 0081; 0088; 0089; 0095; 0103; 0104; 0115; 0116

(2017/09/05)

Palladium nanoparticles stabilized by aqueous vesicles self-assembled from a PEGylated surfactant ionic liquid for the chemoselective reduction of nitroarenes
Vesicles self-assembled from an aqueous PEGylated surfactant ionic liquid solution can be applied for stabilizing palladium nanoparticles, which prove to be an efficient catalytic system for chemoselective hydrogen transfer of nitroarenes using hydrazine hydrate as a hydrogen source. The particle sizes of vesicles are decreased with the increase of ionic liquid's concentrations and relatively small particle sizes are beneficial to the reduction. Moreover, the aqueous catalytic system still stays in reactor by simple extraction, and is reused without further treatment.
Xu, Zhu-bing,Lu, Guo-ping,Cai, Chun
p. 57 - 60
(2017/06/06)

Biomass-Derived Catalysts for Selective Hydrogenation of Nitroarenes
Development of catalytically active materials from biowaste represents an important aspect of sustainable chemical research. Three heterogeneous materials were synthesized from inexpensive biomass-based chitosan and abundant Co(OAc)2 using complexation followed by pyrolysis at various temperatures. These materials were applied in the catalytic hydrogenation of nitroarenes using molecular hydrogen. A variety of diversely functionalized nitroarenes including some pharmaceutically active compounds were converted into aromatic amines in high yields, with high selectivity, and with excellent functional group tolerance. This green protocol has also been implemented for the synthesis of a biologically important TRPC3 inhibitor.
Sahoo, Basudev,Formenti, Dario,Topf, Christoph,Bachmann, Stephan,Scalone, Michelangelo,Junge, Kathrin,Beller, Matthias
p. 3035 - 3039
(2017/08/18)

Direct Hydrogenation of a Broad Range of Amides under Base-free Conditions using an Efficient and Selective Ruthenium(II) Pincer Catalyst
The ruthenium(II) complex, [fac-PNHN]RuH(η1-BH4)(CO) (B; PNHN=8-(2-diphenylphosphinoethyl)aminotrihydroquinoline), is a highly versatile and effective catalyst (loadings of 0.1–1 mol %) for the hydrogenation of a multitude of amides, which include primary, secondary, and tertiary amides, to give their corresponding alcohols and amines in high yields under base-free conditions. All products were confirmed by using GC and GC–MS.
Wang, Zheng,Li, Yong,Liu, Qing-Bin,Solan, Gregory A.,Ma, Yanping,Sun, Wen-Hua
p. 4275 - 4281
(2017/12/02)

Powerful, Thermally Stable, One-Pot-Preparable, and Recyclable Electrophilic Trifluoromethylating Agents: 2,8-Difluoro- and 2,3,7,8-Tetrafluoro-S-(trifluoromethyl)dibenzothiophenium Salts
Although many electrophilic trifluoromethylating agents have been reported to date, practically useful reagents have yet to be developed. S-(Trifluoromethyl)dibenzothiophenium salts, known as Umemoto's reagents, have two significant drawbacks that have ha
Umemoto, Teruo,Zhang, Bin,Zhu, Tianhao,Zhou, Xiaocong,Zhang, Peng,Hu, Song,Li, Yuanqiang
p. 7708 - 7719
(2017/08/14)

Discovery of N-(Naphthalen-1-yl)-N′-alkyl Oxalamide Ligands Enables Cu-Catalyzed Aryl Amination with High Turnovers
A class of N-(naphthalen-1-yl)-N′-alkyl oxalamides have been proven to be powerful ligands, making a coupling reaction of (hetero)aryl iodides with primary amines proceed at 50 °C with only 0.01 mol % of Cu2O and ligand as well as a coupling reaction of (hetero)aryl bromides with primary amines and ammonia at 80 °C with only 0.1 mol % of Cu2O and ligand. A wide range of coupling partners work well under these conditions, thereby providing an easy to operate method for preparing (hetero)aryl amines.
Gao, Jie,Bhunia, Subhajit,Wang, Kailiang,Gan, Lu,Xia, Shanghua,Ma, Dawei
supporting information
p. 2809 - 2812
(2017/06/07)

Chemoselective transfer hydrogenation of nitroarenes by highly dispersed Ni-Co BMNPs
Highly dispread Ni-Co bimetallic nanoparticles (Ni-Co BMNPs) are synthesized and applied as an efficient catalyst in the chemoselective transfer hydrogenation of nitroarenes (CTH) using hydrazine hydrate as the hydrogen donor. The BMNPs can efficiently catalyze the reduction reaction without any additives under mild conditions with high TOF. Significantly higher activity is achieved when compared with corresponding single-component catalysts, optimal composition of the Ni-Co BMNPs was screened which was proved to be crucial in both the selectivity and yields. Excellent performance of Ni-Co BMNPs can be ascribed to the improved dispersion of active sites on the BMNPs surface (compared with Ni NPs) and the electron transfer from cobalt to nickel.
Zhang, Jia-Wei,Lu, Guo-Ping,Cai, Chun
p. 25 - 29
(2016/06/13)

Chemoselective nitro reduction and hydroamination using a single iron catalyst
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.
Zhu, Kailong,Shaver, Michael P.,Thomas, Stephen P.
p. 3031 - 3035
(2016/05/24)

Fe2O3/NGr@C- and Co-Co3O4/NGr@C-catalysed hydrogenation of nitroarenes under mild conditions
An improved hydrogenation of nitroarenes using nano-structured iron- and cobalt-based catalysts is presented. Modifications of the heterogeneous catalysts by N-doped graphene-flakes are crucial for the success of selective reductions. The use of polar solvents and basic additives has a significant positive influence on the rate of reduction of nitroarenes. This allows performing non-noble metal-catalysed hydrogenations under very mild reaction conditions (e.g. 70 °C and 20 bar). On the basis of the obtained catalytic results a heterolytic mechanism for the hydrogenation process is postulated, too.
Formenti, Dario,Topf, Christoph,Junge, Kathrin,Ragaini, Fabio,Beller, Matthias
p. 4473 - 4477
(2016/07/06)

Enhanced chemoselective hydrogenation through tuning the interaction between pt nanoparticles and carbon supports: Insights from identical location transmission electron microscopy and x?ray photoelectron spectroscopy
Ultrasmall-sized platinum nanoparticles (Pt NPs) (～1 nm) supported on carbon nanotubes (CNTs) with nitrogen doping and oxygen functional groups were synthesized and applied in the catalytic hydrogenation of nitroarenes. The advanced identical location transmission electron microscopy (IL-TEM) method was applied to probe the structure evolution of the Pt/CNT catalysts in the reaction. The results indicate that Pt NPs supported on CNTs with a high amount of nitrogen doping (Pt/H-NCNTs) afford 2-fold activity to that of Pt NPs supported on CNTs with oxygen functional groups (Pt/oCNTs) and 4-fold to that of the commercial Pt NPs supported on active carbon (Pt/C) catalyst toward nitrobenzene. The catalytic performance of Pt/H-NCNTs remained constant during four cycles, whereas the activity of the Pt/oCNTs was halved at the second cycle. Compared with Pt/oCNTs, Pt/H-NCNTs exhibited a higher selectivity (>99%) in chemoselective hydrogenation of halonitrobenzenes to haloanilines due to the electron-rich chemical state of Pt NPs. The strong metal?support interaction along with the electron-donor capacity of nitrogen sites on H-NCNTs are capable of stabilizing the Pt NPs and achieving related catalytic recyclability as well as approximately 100% selectivity. The catalyst also delivers exclusively selective hydrogenation toward nitro groups for a wide scope of substituent nitroarenes into their corresponding anilines.
Shi, Wen,Zhang, Bingsen,Lin, Yangming,Wang, Qi,Zhang, Qiang,Su, Dang Sheng
p. 7844 - 7854
(2018/05/23)

A Metal and Base-Free Chemoselective Primary Amination of Boronic Acids Using Cyanamidyl/Arylcyanamidyl Radical as Aminating Species: Synthesis and Mechanistic Studies by Density Functional Theory
An efficient, metal and base-free, chemoselective synthesis of aryl-, heteroaryl-, and alkyl primary amines from the corresponding boronic acids has been achieved at ambient temperature mediated by [bis(trifluoroacetoxy)iodo]benzene (PIFA) and N-bromosuccinimide (NBS) using cyanamidyl/arylcyanamidyl radicals as the aminating species. The primary amine compounds were initially obtained as their corresponding ammonium trifluoroacetate salts which, on treatment with aq NaOH, provide the free amines. Finally, the primary amines were isolated through column chromatography over silica-gel using hexane-EtOAc solvent system as the eluent. The reactions are sufficiently fast, completing within 1 h. Quantum chemical calculations in combination with experimental observations validate that the ipso amination of substituted boronic acids involves the formation of cyanamidyl/arylcyanamidyl radical, followed by regiospecific interaction of its nitrile-N center with boron atom of the boronic acids, leading to chemoselective primary amination.
Chatterjee, Nachiketa,Arfeen, Minhajul,Bharatam, Prasad V.,Goswami, Avijit
p. 5120 - 5127
(2016/07/06)

Efficient and highly selective boron-doped carbon materials-catalyzed reduction of nitroarenes
Exploring the potential catalytic applications of boron-doped carbon materials is a fascinating challenge. Here we describe that boron-doped onion-like carbon and carbon nanotubes as metal-free catalysts exhibit excellent catalytic activity and stability in nitroarene reduction under a stoichiometric amount of reductant.
Lin, Yangming,Wu, Shuchang,Shi, Wen,Zhang, Bingsen,Wang, Jia,Kim, Yoong Ahm,Endo, Morinobu,Su, Dang Sheng
p. 13086 - 13089
(2015/08/18)

Iridium-catalyzed transfer hydrogenation of nitroarenes to anilines
A simple and general homogeneous catalyst system composed of commercially available [Ir(cod)Cl]2 and 1,10-phenanthroline has been developed for the selective transfer hydrogenation of nitroarenes to anilines. It utilized the readily accessible 2-propanol as a hydrogen donor and had wide substrate scope. A careful mechanistic investigation through real-time detection and a series of controlled experiments with possible intermediates was also carried out, which showed that the transformation proceeds via both phenylhydroxylamine and azobenzene intermediates and the reduction of hydrazobenzene leading to aniline might be the rate-determining step.
Chen, Shujie,Lu, Guoping,Cai, Chun
p. 5360 - 5365
(2015/07/07)

Metal and base free synthesis of primary amines via ipso amination of organoboronic acids mediated by [bis(trifluoroacetoxy)iodo]benzene (PIFA)
A metal and base free synthesis of primary amines has been developed at ambient temperature through ipso amination of diversely functionalized organoboronic acids, employing a combination of [bis(trifluoroacetoxy)iodo]benzene (PIFA)-N-bromosuccinimide (NBS) and methoxyamine hydrochloride as the aminating reagent. The amines were primarily obtained as their trifluoroacetate salts which on subsequent aqueous alkaline work up provided the corresponding free amines. The combination of PIFA-NBS is found to be the mildest choice compared to the commonly used strong bases (e.g. n-BuLi, Cs2CO3) for activating the aminating agent. The reaction is expected to proceed via activation of the aminating reagent followed by B-N 1,2-aryl migration.
Chatterjee, Nachiketa,Goswami, Avijit
supporting information
p. 7940 - 7945
(2015/07/27)

Iron-catalysed, general and operationally simple formal hydrogenation using Fe(OTf)3 and NaBH4
An operationally simple and environmentally benign formal hydrogenation protocol has been developed using highly abundant iron(iii) salts and an inexpensive, bench stable, stoichiometric reductant, NaBH4, in ethanol, under ambient conditions. This reaction has been applied to the reduction of terminal alkenes (22 examples, up to 95% yield) and nitro-groups (26 examples, up to 95% yield). Deuterium labelling studies indicate that this reaction proceeds via an ionic rather than radical mechanism.
MacNair, Alistair J.,Tran, Ming-Ming,Nelson, Jennifer E.,Sloan, G. Usherwood,Ironmonger, Alan,Thomas, Stephen P.
supporting information
p. 5082 - 5088
(2014/07/08)

METHODS FOR PREPARING ALKYLFURANS
Provided herein are methods for preparing alkylfurans, such as 2,5-dialkylfurans and 2-alkylfurans. Furfural or 5-alkylfurfural can be reacted with aniline or diaminobenzene, or derivatives thereof, to form the corresponding imine, which can be reduced to form alkylfurans and to regenerate the aniline or diaminobenzene, or derivatives thereof. The alkylfuran may be, for example, 2,5-dimethylfuran or 2-methylfuran.
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Paragraph 0158-0160

(2014/10/04)

Synthesis and characterization of copper nanoparticles supported on reduced graphene oxide as a highly active and recyclable catalyst for the synthesis of formamides and primary amines
We report here the synthesis of reduced graphene oxide supported copper nanoparticles (rGO/Cu NPs) from copper (II) sulfate pentahydrate and graphite precursors using a simple protocol. The catalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) and energy dispersive X-ray spectroscopy (EDS). The rGO/Cu NPs is proved to be a useful heterogeneous catalyst in Cu-catalyzed formamidation and amination of arylboronic acids. The catalyst can be recovered by simple filtration from the reaction mixture and reused several times without significant loss of catalytic activity.
Fakhri, Parisa,Jaleh, Babak,Nasrollahzadeh, Mahmoud
p. 17 - 22
(2014/01/06)

Green recyclable CuO-CeO2 nanocomposite catalyzed amination of aryl halides with aqueous ammonia in water
CuO-CeO2 nanocomposite as a green recyclable catalyst, catalyzed amination of aryl halides with aqueous ammonia in water. This catalyst can be easily recovered by simple filtration and recycled up to 5 consecutive runs with consistent activity. The procedure provides some advantages such as simple work-up, clean procedure, relatively short reaction times and high yields of the products. Efficient procedure for the amination of aryl halides catalyzed by Cu-CeO2 nanocomposite. Copyright
Albadi, Jalal,Mansournezhad, Azam
p. 396 - 398
(2014/06/10)

Amination of aryl halides with aqueous ammonia catalyzed by green recyclable poly(4-vinylpyridine) -supported copper iodide nanoparticles catalyst
In this research efficient procedure for the amination of aryl halides with aqueous ammonia in the presence of poly(4-vinylpyridine)-supported copper iodide nanoparticles catalyst is reported. A wide range of aryl halides including aryl iodides and aryl bromides are converted into the corresponding aniline derivatives. The experimental procedure with poly(4-vinylpyridine)-supported copper iodide nanoparticles catalyst is quite straightforward and it is recycled up to 3 consecutive runs by simple filtration.
Albadi, Jalal,Shiran, Jafar Abbasi,Mansournezhad, Azam
p. 900 - 903
(2015/02/05)

Mild and highly selective palladium-catalyzed monoarylation of ammonia enabled by the use of bulky biarylphosphine ligands and palladacycle precatalysts
A method for the Pd-catalyzed arylation of ammonia with a wide range of aryl and heteroaryl halides, including challenging five-membered heterocyclic substrates, is described. Excellent selectivity for monoarylation of ammonia to primary arylamines was achieved under mild conditions or at rt by the use of bulky biarylphosphine ligands (L6, L7, and L4) as well as their corresponding aminobiphenyl palladacycle precatalysts (3a, 3b, and 3c). As this process requires neither the use of a glovebox nor high pressures of ammonia, it should be widely applicable.
Cheung, Chi Wai,Surry, David S.,Buchwald, Stephen L.
supporting information
p. 3734 - 3737
(2013/08/23)

Magnetically separable CuFe2O4 nanoparticles in PEG: A recyclable catalytic system for the amination of aryl iodides
A recyclable catalytic system comprising magnetically separable CuFe 2O4 nanoparticles in a poly(ethylene glycol) medium has been established as an inexpensive, nontoxic, environmentally benign system for the amination of aryl iodides with aqueous ammonia. A wide variety of aryl iodides underwent amination to afford the corresponding aryl amines in moderate to good yields. The catalytic system was recycled five times with consistent activity. Georg Thieme Verlag Stuttgart . New York.
Kumar, A. Suresh,Ramani,Sreedhar
supporting information
p. 938 - 942
(2013/06/27)

Rapid reduction of heteroaromatic nitro groups using catalytic transfer hydrogenation with microwave heating
A method for the rapid, safe reduction of heteroaromatic and aromatic nitro groups to amines is described using catalytic transfer hydrogenation under microwave heating conditions. Commonly available Pd/C or Pt/C catalyst is extremely effective with 1,4-cyclohexadiene as the hydrogen transfer source. In the case of substrates containing potentially labile aromatic halogens, Pt/C is effective and results in little or no dehalogenation. In general, the reactions are complete within 5 min at 120 °C.
Quinn, John F.,Bryant, Cole E.,Golden, Kathryn C.,Gregg, Brian T.
experimental part
p. 786 - 789
(2010/03/24)

Synthesis of 1-(R-Phenyl)-5-(R-Methyl)-1H-1,2,3-triazole-4-carboxylic acids by one-pot tandem reaction
Substituted 1H-1,2,3-triazole-4-carboxylic acids were synthesized by a three-component reaction of arylazides, ethyl 4-chloro-3-oxobutanoate, and either O-or S-nucleophiles in the presence of a base catalyst. The reaction most probably proceeded as a [3+2] cyclocondensation reaction between arylazide and ethyl 4-chloro-3-oxobutanoate with the further nucleophilic substitution of chlorine in the chloromethyl group. Reaction optimization was performed to carry out the reaction with an O-nucleophile. Conditions were found under which diethyl 2,5-dihydroxyterephthalate (the product of self-condensation of two molecules of ethyl 4-chloro-3-oxobutanoate with the further oxidation by azide) was obtained. Copyright
Pokhodylo, Nazariy T.,Matiychuk, Vasyl S.,Obushak, Mykola D.
experimental part
p. 1932 - 1938
(2010/09/05)

CuI/4-hydro-L-proline as a more effective catalytic system for coupling of aryl bromides with N-boc hydrazine and aqueous ammonia
(Chemical Equation Presented) CuI/4-hydroxy-L-proline-catalyzed coupling of aryl bromides and N-Boc hydrazine takes place in DMSO at 80°C to give N-aryl hydrazides. When aryl iodides are employed, this reaction completes at 50°C and no ligand is required. Under the catalysis of CuI/4-hydroxy-L- proline, the coupling reaction of aqueous ammonia with aryl bromides proceeds smoothly at 50°C to afford primary arylamines. In this case K 2CO3 is found as a better base than Cs2CO 3. These processes allow assembly of N-aryl hydrazides and primary arylamines that bear a wide range of functional groups including hydroxyl, amine, trifluoromethyl, ester, nitro, and ketone.
Jiang, Liqin,Lu, Xu,Zhang, Hui,Jiang, Yongwen,Ma, Dawei
experimental part
p. 4542 - 4546
(2009/09/25)