- Helical structures of tribenzylamine supramolecular complexes with [CoCl4]2-/[CuCl4]2-, and conformational comparisons of tribenzylamine in different supramolecular complexes
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The compound tribenzylamine (TBA) and its derivatives are a type of classical tripodal ligands in building up diversity of supramolecular arrays or networks. In the present contribution, we described two new supramolecular complexes 2[C21H22N+]·[CoCl 4]2-·(1) and 2[C21H22N +]·[CuCl4]2- (2) by reacting protonated TBA with CoCl2·6H2O/CuCl2·2H 2O. Different from previous TBA supramolecular complexes, these two supramolecular complexes were easier to obtain by grinding protonated TBA and CoCl2·6H2O/CuCl2·2H2O in an agate mortar than using conventional solution method. The two supramolecular complexes form fascinating 3D helical architectures, with two types of interwoven helical chains involved inside the structures. A comparison of the geometries of TBA in these two supramolecular complexes with the previously reported TBA supramolecular complexes shows that the significant differences are due to the conformation of the three arms of phenyl rings around the N center.
- Guan, Hong-Yu,Shao, Hui-De,Li, Lei,Jia, Jian-Ming,Guo, Fang
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- Synthesis and structural studies of tris-2-chlorobenzylamine and tris-2-bromobenzylamine
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The tris-2-chloro and 2-bromotribenzylamines are prepared from aqueous ammonia and 2-chlorobenzyl chloride and 2-bromobenzyl bromide, respectively, in ethanol. Recrystallization yielded colorless cubes of each product. The crystal structures are each solved in space group P1, and are isostructural. The tris-2-chloro compound, 1, has a = 7.4226(5) A, b = 9.0825(7) A, c = 14.529(1) A, α = 78.279(1)°, β = 82.389(1)°, γ = 84.661(1)°, and V = 948.41(12) A3 with Z = 2, and d calc = 1.368 Mg/m3. The tris-2-bromo analog, 2, has a = 7.6569(11) A, b = 9.0922(13) A, c = 14.614(2) A, α = 79.286(2)°, β = 81.777(2)°, γ = 85.401(2)°, and V = 987.9(2) A3 with Z = 2, and dcalc = 1.762 Mg/m 3. Lithium-halogen exchange experiments conducted in tetrahydrofuran at -78°C using n-butyl lithium revealed that no exchange occurred for the tris-2-chloro compound, but did occur for the tris-2-bromo analog to yield tribenzylamine upon quench and work-up.
- Chen, Qing,Buss, Carrie E.,Young Jr., Victor G.,Fox, Stephen
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- Layered structures constructed by second-sphere coordination via N-H···Cl and C-H···Cl hydrogen bonding: Synthesis and crystal structures of tribenzylamine and [MCl6] (M=Sn, Re, and Te)
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A series of second-sphere coordination complexes of tribenzylamine (L1) and [MCI6] (M=Sn, Re, Te) have been synthesized and characterized by spectroscopic techniques (IR, NMR) and single-crystal X-ray diffraction. The main driving force for the encapsulation of [MCl6] and recognition with L1 is the second-sphere coordination of metal halides by the amide protons of the ligand via hydrogen bonding (N-H···Cl-M and C-H···Cl-M); new layered structures are described. Thermal stability and irreversible behavior of second-sphere coordination complexes [L2] 0.5[TeCl6]2- · HCl · (H3O)+ · 0.5H2O (L2=N,N,N′,N′-tetrabenzyl-ethylenediamine) in contact with water vapor are also described.
- Guo, Fang,Lu, Na,Tong, Jian,Luan, Yu-Bo,Guo, Wen-Sheng
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- Simplified preparation of a graphene-co-shelled Ni/NiO@C nano-catalyst and its application in theN-dimethylation synthesis of amines under mild conditions
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The development of Earth-abundant, reusable and non-toxic heterogeneous catalysts to be applied in the pharmaceutical industry for bio-active relevant compound synthesis remains an important goal of general chemical research.N-methylated compounds, as one of the most essential bioactive compounds, have been widely used in the fine and bulk chemical industries for the production of high-value chemicals. Herein, an environmentally friendly and simplified method for the preparation of graphene encapsulated Ni/NiO nanoalloy catalysts (Ni/NiO@C) was developed for the first time, for the highly selective synthesis ofN-methylated compounds using various functional amines and aldehydes under easy to handle, and industrially applicable conditions. A large number of primary and secondary amines (more than 70 examples) could be converted to the correspondingN,N-dimethylamines with the participation of different functional aldehydes, with an average yield of over 95%. A gram-scale synthesis also demonstrated a similar yield when compared with the benchmark test. In addition, it was further proved that the catalyst could easily be recycled because of its intrinsic magnetism and reused up to 10 times without losing its activity and selectivity. Also, for the first time, the tandem synthesis ofN,N-dimethylamine products in a one-pot process, using only a single earth-abundant metal catalyst, whose activity and selectivity were more than 99% and 94%, respectively, for all tested substrates, was developed. Overall, the advantages of this newly developed method include operational simplicity, high stability, easy recyclability, cost-effectiveness of the catalyst, and good functional group compatibility for the synthesis ofN-methylation products as well as the industrially applicable tandem synthesis process.
- Liu, Jianguo,Ma, Longlong,Song, Yanpei,Zhang, Mingyue,Zhuang, Xiuzheng
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supporting information
p. 4604 - 4617
(2021/06/30)
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- Hydrosilylative reduction of primary amides to primary amines catalyzed by a terminal [Ni-OH] complex
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A terminal [Ni-OH] complex1, supported by triflamide-functionalized NHC ligands, catalyzes the hydrosilylative reduction of a range of primary amides into primary amines in good to excellent yields under base-free conditions with key functional group tolerance. Catalyst1is also effective for the reduction of a variety of tertiary and secondary amides. In contrast to literature reports, the reactivity of1towards amide reduction follows an inverse trend,i.e., 1° amide > 3° amide > 2° amide. The reaction does not follow a usual dehydration pathway.
- Bera, Jitendra K.,Pandey, Pragati
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supporting information
p. 9204 - 9207
(2021/09/20)
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- Reduction of Amides to Amines with Pinacolborane Catalyzed by Heterogeneous Lanthanum Catalyst La(CH2C6H4NMe2- o)3@SBA-15
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Hydroboration of amides is a useful synthetic strategy to access the corresponding amines. In this contribution, it was found that the supported lanthanum benzyl material La(CH2C6H4NMe2-o)3@SBA-15 was highly active for the hydroboration of primary, secondary, and tertiary amides to amines with pinacolborane. These reactions selectively produced target amines and showed good tolerance for functional groups such as -NO2, -halogen, and -CN, as well as heteroatoms such as S and O. This reduction procedure exhibited the recyclable and reusable property of heterogeneous catalysts and was applicable to gram-scale synthesis. The reaction mechanisms were proposed based on some control experiments and the previous literature. This is the first example of hydroborative reduction of amides to amines mediated by heterogeneous catalysts.
- Guo, Chenjun,Zhang, Fangcao,Yu, Chong,Luo, Yunjie
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supporting information
p. 13122 - 13135
(2021/08/31)
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- Rapid Multialkylation of Aqueous Ammonia with Alcohols by Heterogeneous Iridium Catalyst under Simple Conditions
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This paper reports the synthesis of tertiary and secondary amines from aqueous ammonia and benzylic alcohols by titania-supported iridium catalyst. It is a successful example of heterogeneous systems at moderate temperature without either additional solvent or high pressure. The catalytic system showed good tolerance to the atmosphere condition and performed rapidly to give tribenzylamine a yield of over 99 % within 6 hours in argon. The crystal structure of titania supports for iridium catalysts strongly affected their activity. The catalysis smoothly proceeded on larger scales. The catalyst could be easily reused and run at least for 5 cycles without significant loss of activity. The highly-dispersed iridium species of less than 2 nm in diameter would be responsible for the excellent catalytic activity. This catalyst is well applicable in multialkylation of aqueous ammonia with various primary and secondary benzylic alcohols.
- Yu, Han,Ma, Lin,Wada, Kenji,Kurihara, Ryohsuke,Feng, Qi,Uemura, Shinobu,Isoda, Kyosuke
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p. 3588 - 3593
(2021/07/02)
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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
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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.
- Fan, Qing-Hua,Liu, Xintong,Luo, Zhenli,Pan, Yixiao,Xu, Lijin,Yang, Ji,Yao, Zhen,Zhang, Xin
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p. 5205 - 5211
(2021/07/29)
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- Reductive Alkylation of Azides and Nitroarenes with Alcohols: A Selective Route to Mono- And Dialkylated Amines
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Herein, we demonstrated an efficient protocol for reductive alkylation of azides/nitro compounds via a borrowing hydrogen (BH) method. By following this protocol, selective mono- and dialkylated amines were obtained under mild and solvent-free conditions. A series of control experiments and deuterium-labeling experiments were performed to understand this catalytic process. Mechanistic studies suggested that the Ir(III)-H was the active intermediate in this reaction. KIE study revealed that the breaking of the C-H bond of alcohol might be the rate-limiting step. Notably, this solvent-free strategy disclosed a high TON of around 5600. Based on kinetic studies and control experiments, a metal-ligand cooperative mechanism was proposed.
- Borthakur, Ishani,Joshi, Abhisek,Kundu, Sabuj,Maji, Milan
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- Cp*Ir complex bearing a flexible bridging and functional 2,2′-methylenebibenzimidazole ligand as an auto-tandem catalyst for the synthesis of N-methyl tertiary amines from imines via transfer hydrogenation/N-methylation with methanol
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A Cp*Ir complex bearing a flexible bridging and functional 2,2′-methylenebibenzimidazole ligand was designed, synthesized, and found to be a general and efficient auto-tandem catalyst for the synthesis of N-methyl tertiary amines from imines via transfer hydrogenation/N-methylation with methanol as both hydrogen source and methylating reagent. In the presence of [Cp*Ir(2,2′-CH2BiBzImH2)Cl][Cl], a range of desirable products were obtained in high yields with nearly complete selectivities. The reaction is highly attractive due to the highly atom economy, and minimal consumption of chemicals and energy. Notably, this research exhibits new potential of metal–ligand bifunctional catalysts for the activation of methanol as C1 source for organic synthesis.
- Ai, Yao,Chen, Xiaozhong,Li, Feng,Liu, Peng,Yang, Chenchen,Yang, Jiazhi
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p. 325 - 334
(2021/10/07)
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- Catalytic Deoxygenation of Amine and Pyridine N-Oxides Using Rhodium PCcarbeneP Pincer Complexes
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Rhodium PCcarbeneP pincer complexes 1-L (L = PPh3, PPh2(C6F5), PCy3) readily facilitate deoxygenation of amine and pyridine N-oxides. The resulting complexes exhibit δ2-C= O coordination of the resulting keto POP pincer ligand. These δ2-Ca? O linkages in the metalloepoxide complexes are readily reduced by isopropyl alcohol and various benzylic alcohols. Thus, efficient catalytic deoxygenation of amine and pyridine N-oxides is possible using complexes 1-L and isopropyl alcohol. This represents a pioneering example of PCcarbeneP pincer complexes being used as catalysts for catalytic deoxygenation.
- Tinnermann, Hendrik,Sung, Simon,Cala, Beatrice A.,Gill, Hashir J.,Young, Rowan D.
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p. 797 - 803
(2020/03/13)
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- Homoleptic Bis(trimethylsilyl)amides of Yttrium Complexes Catalyzed Hydroboration Reduction of Amides to Amines
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Homoleptic lanthanide complex Y[N(TMS)2]3 is an efficient homogeneous catalyst for the hydroboration reduction of secondary amides and tertiary amides to corresponding amines. A series of amides containing different functional groups such as cyano, nitro, and vinyl groups were found to be well-tolerated. This transformation has also been nicely applied to the synthesis of indoles and piribedil. Detailed isotopic labeling experiments, control experiments, and kinetic studies provided cumulative evidence to elucidate the reaction mechanism.
- Ye, Pengqing,Shao, Yinlin,Ye, Xuanzeng,Zhang, Fangjun,Li, Renhao,Sun, Jiani,Xu, Beihang,Chen, Jiuxi
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supporting information
p. 1306 - 1310
(2020/02/22)
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- Method for synthesizing tertiary amine derivative by catalyzing hydroboration reaction of tertiary amide by rare earth
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The invention discloses a method for synthesizing a tertiary amine derivative by catalyzing a hydroboration reaction of tertiary amide by rare earth. Under the protection of nitrogen, in a rare earthcatalysis system, the tertiary amine derivative is prepared through a hydrogen transfer reduction reaction catalyzed by rare earth with tertiary amide and pinacol borane as raw materials. The method has the advantages and effects that a novel synthesis process is utilized, and the tertiary amine derivative prepared by using the method disclosed by the invention is high in quality and stable in process; the raw materials are widely sourced or easy to prepare and store, and the reaction yield is high; and in addition, a catalyst can be directly commercially purchased or is easily, directly and simply synthesized, and can be used in actual production.
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Paragraph 0016; 0017
(2020/02/27)
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- Selenoimidazolium Salts as Supramolecular Reagents for Protein Alkylation
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Se-benzyl selenoimidazolium salts are characterized by remarkable alkyl-transfer potential under physiological conditions. Structure-activity relationship studies show that selective monoalkylation of primary amines depends on supramolecular interactions
- Lim, David,Wen, Xiaojin,Seebeck, Florian P.
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p. 3515 - 3520
(2020/09/21)
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- Amination of aliphatic alcohols with urea catalyzed by ruthenium complexes: effect of supporting ligands
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In the present study, ruthenium-catalyzed amination of alcohols by urea as a convenient ammonia carrier in the presence of free diphosphine ligands has been described. A number of ruthenium-phosphine complexes have been studied among which, [(Cp)RuCl(dppe)] was found as an efficient catalyst for alcohol amination reaction. The crystal structures of two new half-sandwich ruthenium complexes, [(Cp)RuCl(dppe)] and [(C6H6)RuCl2(PHEt2)], were determined by X-ray crystallographic analysis. Also the effect of using different supporting phosphines, ratio of raw materials and reaction temperature on conversion and selectivity was investigated. Under optimum reaction conditions high conversion (98percent) and chemo-selectivity toward secondary amines were obtained.
- Dindar, Sara,Nemati Kharat, Ali
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- N-Benzylation of primary amines using magnetic Fe3O4 nanoparticles functionalized with hexamethylenetetramine as an efficient and recyclable heterogeneous catalyst
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Herein we report, a new, simple and mild procedure for N-benzylation and N,N-dibenzylation of anilines through the reaction of aniline derivatives and benzyl bromide at 60 °C in EtOH in the presence of catalytic amounts of magnetic Fe3O4 nanoparticles functionalized with hexamethylenetetramine (Fe3O4?SiO2?Propyl-HMTA). The title compounds were formed in high purity and their structures characterized by spectral analysis. The results also showed that the magnetic nanoparticle catalyst had significant advantages including, simplicity of preparation, heterogeneity, stability and recyclability. Moreover, the catalyst was characterized by various methods, such as FT-IR, SEM, VSM, TEM, TGA and XRD, after the reaction to compare with its structure before reaction.
- Ghorbani-Vaghei, Ramin,Mirzaei-Mosbat, Maryam,Noori, Samira
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- Rational Optimization of Lewis-Acid Catalysts for Direct Alcohol Amination, Part 2 – Titanium Triflimide as New Active Catalyst
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The reactivity of a new titanium triflimide salt (see Part 1) was investigated for the direct amination of alcohols. The combination of this new Lewis acid with pyridine-based ligands allowed a significant increase of activity. The scope of the reaction was increased compared to other Lewis-acid-based protocols. Finally, mechanistic insights based on EPR spectroscopy and DFT calculations are provided.
- Payard, Pierre-Adrien,Finidori, Céline,Guichard, Laurélia,Cartigny, Damien,Corbet, Matthieu,Khrouz, Lhoussain,Bonneviot, Laurent,Wischert, Raphael,Grimaud, Laurence,Pera-Titus, Marc
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supporting information
p. 3225 - 3228
(2020/06/08)
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- Iridium complexes with a new type of N^N′-donor anionic ligand catalyze the N-benzylation of amines via borrowing hydrogen
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The development of efficient and eco-friendly methods for the synthesis of elaborate amines is highly desired as they are valuable chemicals. The catalytic alkylation of amines using alcohols as alkylating agents, through the so-called borrowing hydrogen process, satisfies several of the principles of green chemistry. In this paper, four neutral half-sandwich complexes of Ru(II), Rh(III), and Ir(III) have been synthesized and tested as catalysts in the N-benzylation of amines with benzyl alcohol. The new derivatives contain a N^N′ anionic ligand derived from 5-(pyridin-2-ylmethylene)hydantoin (Hpyhy) that has never been tested in metal complexes with catalytic applications. In particular, the Ir derivatives, [(Cp*)IrX(pyhy)] (X = Cl or H), exhibit high activity along with good selectivity in the process. Indeed, the scope of the optimized protocol has been proved in the benzylation of several primary and secondary amines. The selectivity towards monoalkylated or dialkylated amines has been tuned by adjusting the amine:alcohol ratio and the reaction time. Experimental results support a mechanism consisting of three consecutive steps, two of which are Ir catalyzed, and a favorable condensation step without the assistance of the catalyst. Moreover, an unproductive competitive pathway can operate when the reaction is performed in open-air vessels, due to the irreversible release of H2. This route is hampered when the reaction is carried out in close vessels, likely because the release of H2 is reversed through metal-based heterolytic cleavage. From our viewpoint, these results show the potential of the new catalysts in a very attractive and promising methodology for the synthesis of amines.
- Ruiz-Casta?eda, Margarita,Rodríguez, Ana M.,Aboo, Ahmed H.,Manzano, Blanca R.,Espino, Gustavo,Xiao, Jianliang,Jalón, Félix A.
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- Direct benzylation of amines with benzylic alcohols catalyzed by palladium/phosphine-borane catalyst system
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Direct catalytic benzylation of amines with benzylic alcohols to give benzylamines has been newly developed by using palladium/phosphine-borane catalyst system. In this catalytic reaction, the linking between both phosphine and borane moieties in the ligand is very important. Hydroxy group of benzylic alcohols is activated by Lewis acidic borane to form a benzylpalladium intermediate which is attacked by amines to give benzylamine products.
- Onodera, Gen,Kumagae, Hidenobu,Nakamura, Daiki,Hayasaki, Takuto,Fukuda, Tsutomu,Kimura, Masanari
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supporting information
(2020/11/04)
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- Direct Catalytic Reductive N-Alkylation of Amines with Carboxylic Acids: Chemoselective Enamine Formation and further Functionalizations
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Direct reductive N-alkylation of secondary amines with carboxylic acids using molybdenum hexacarbonyl (5 mol %) as catalyst and diethoxymethylsilane as reducing agent generate enamines in a straightforward fashion in high yields. The formed enamines are without the need for isolation or purification further reacted with trimethylsilyl cyanide in the same reaction flask to yield α-amino nitriles in good yields. In the optimized reaction conditions equimolar amounts of carboxylic acid and amine are reacted under neat conditions, and a catalytic amount of trifluoroethanol (0.1 mol %) is added along with TMSCN for the cyanation step. The reductive N-alkylation reaction is demonstrated to be highly chemoselective, tolerating a multitude of different functional groups present in the starting carboxylic acids and amines. The reaction is scalable and the generated α-amino nitriles are converted to other useful compounds, e.g., α-amino acids or amino-tetrazoles. In addition, the intermediate enamines are further transformed into triazolines, sulfonylformamidines, pyrimidinediones, and TMS-propargylamines, respectively, in high yields under mild reaction conditions. Benzoic acids react with secondary amines under similar conditions to give tertiary amines in high yields, and using this methodology, the biologically active compound Piribedil was isolated in 80% yield in a direct one-pot reaction setup.
- Trillo, Paz,Adolfsson, Hans
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p. 7588 - 7595
(2019/08/20)
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- B(C6F5)3-Catalyzed Deoxygenative Reduction of Amides to Amines with Ammonia Borane
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The first B(C6F5)3-catalyzed deoxygenative reduction of amides into the corresponding amines with readily accessible and stable ammonia borane (AB) as a reducing agent under mild reaction conditions is reported. This metal-free protocol provides facile access to a wide range of structurally diverse amine products in good to excellent yields, and various functional groups including those that are reduction-sensitive were well tolerated. This new method is also applicable to chiral amide substrates without erosion of the enantiomeric purity. The role of BF3 ? OEt2 co-catalyst in this reaction is to activate the amide carbonyl group via the in situ formation of an amide-boron adduct. (Figure presented.).
- Pan, Yixiao,Luo, Zhenli,Han, Jiahong,Xu, Xin,Chen, Changjun,Zhao, Haoqiang,Xu, Lijin,Fan, Qinghua,Xiao, Jianliang
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supporting information
p. 2301 - 2308
(2019/01/30)
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- Hydrosilylative Reduction of Tertiary Amides to Amines Catalyzed by N-(Phosphinoaryl)anilido Complexes of Iron and Cobalt
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The synthesis and structural characterization of low-coordinate Fe(II) and Co(II) complexes supported by the monoanionic P,N-ligand N-(2-dicyclohexylphosphinophenyl)-2,6-diisopropylanilide are described. A three-coordinate (P,N)Fe-hexamethyldisilazide complex (2), and four-coordinate (P,N)Fe- (3-Fe) and (P,N)Co-alkyl (3-Co) complexes were evaluated as pre-catalysts for the hydrosilylative reduction of amides with PhSiH3 (5 mol % pre-catalyst, 1 equiv. PhSiH3, 80 °C, 1–24 h). The Fe complex 2 proved to be more broadly effective for the reduction of a variety of tertiary amide substrates, and was shown to mediate the reduction of N,N-dibenzylbenzamide at a loading of 1 mol %, to achieve near quantitative formation of tribenzylamine in 1 h (80 °C). Complex 2 also proved effective for the hydrosilylation of tertiary amides under ambient conditions (5 mol % Fe, 24 h), which is a unique example of room temperature amide hydrosilylation mediated by an Fe catalyst without the need for photochemical activation. Given the widespread use of amide reduction protocols in synthesis, the development of efficient Fe-based catalysts that operate under mild conditions is an important target.
- Hale, Dylan J.,Murphy, Luke J.,McDonald, Robert,Ferguson, Michael J.,Turculet, Laura
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p. 3818 - 3827
(2019/06/17)
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- A comparative analysis of hydrosilative amide reduction catalyzed by first-row transition metal (Mn, Fe, Co, and Ni): N -phosphinoamidinate complexes
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A comparative study of the performance of (PN)M(N(SiMe3)2) (M = Mn, Fe, Co, and Ni) pre-catalysts supported by N-phosphinoamidinate ligation, as well as M(N(SiMe3)2)n (M = Li, Na, K, Mn, Fe, and Co) pre-catalysts, in the hydrosilative reduction of selected tertiary amide test substrates using PhSiH3 is reported. Encouraged by the performance observed herein for (PN)Ni(N(SiMe3)2) in the reduction of both N,N-dibenzylbenzamide and N,N-diisopropylbenzamide, further competitive testing involving the known complex (PN)Ni(NHdipp) (dipp = 2,6-diisopropylphenyl), as well as the new and crystallographically characterized mononuclear complexes (PN)Ni(OR) (R = 2,6-dimethylphenyl or tBu), revealed (PN)Ni(OtBu) to be particularly effective in such reduction chemistry, including transformations involving the secondary amides N-benzylbenzamide and caprolactam.
- Macaulay, Casper M.,Ogawa, Takahiko,McDonald, Robert,Sydora, Orson L.,Stradiotto, Mark,Turculet, Laura
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p. 9581 - 9587
(2019/07/10)
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- Iridium-Catalyzed Alkylation of Amine and Nitrobenzene with Alcohol to Tertiary Amine under Base- and Solvent-Free Conditions
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Herein, an efficient and green method for the selective synthesis of tertiary amines has been developed that involves iridium-catalyzed alkylation of various primary amines with aromatic or aliphatic alcohols. Notably, the catalytic protocol enables this transformation in the absence of additional base and solvent. Furthermore, the alkylation of nitrobenzene with primary alcohol to tertiary amine has also been achieved by the same catalytic system. Deuterium-labeling experiments and a series of control experiments were conducted, and the results suggested that an intermolecular borrowing hydrogen pathway might exist in the alkylation process.
- Li, Chao,Wan, Ke-Feng,Guo, Fu-Ya,Wu, Qian-Hui,Yuan, Mao-Lin,Li, Rui-Xiang,Fu, Hai-Yan,Zheng, Xue-Li,Chen, Hua
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p. 2158 - 2168
(2019/05/16)
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- Selective Synthesis of Secondary Amines from Nitriles by a User-Friendly Cobalt Catalyst
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Selective hydrogenation/reductive amination of nitriles to secondary amines catalyzed by an inexpensive and user-friendly cobalt complex, (Xantphos)CoCl2, is reported. The use of (Xantphos)CoCl2 and ammonia borane (NH3?BH3) combination affords the selective reduction of nitriles to symmetrical secondary amines, whereas the employment of (Xantphos)CoCl2 and dimethylamine borane (Me2NH?BH3) along with external amines produce unsymmetrical secondary amines and tertiary amines. The general applicability of this methodology is demonstrated by the synthesis of 43 symmetrical and unsymmetrical secondary and tertiary amines bearing diverse functionalities. (Figure presented.).
- Sharma, Dipesh M.,Punji, Benudhar
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p. 3930 - 3936
(2019/07/12)
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- Tertiary amine synthesis method
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The invention relates to the technical field of organic matters, and specifically relates to a tertiary amine synthesis method. Under the action of a catalyst, in the absence of solvent and alkali, primary amine, secondary amine, or a nitro derivative reacts with alcohol to prepare tertiary amine. The provided synthesis method has the advantages that no toxic solvent is used during the preparationprocess, the method is green and environmentally friendly, the atom utilization rate is high, the operation is simple, the application range of the functional groups and substrate is wide, and the yield of tertiary amine is high, in particular reactions between aliphatic amine and alcohol.
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Paragraph 0021-0026
(2019/01/24)
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- Manganese(III) Porphyrin-Catalyzed Dehydrogenation of Alcohols to form Imines, Tertiary Amines and Quinolines
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Manganese(III) porphyrin chloride complexes have been developed for the first time as catalysts for the acceptorless dehydrogenative coupling of alcohols and amines. The reaction has been applied to the direct synthesis of imines, tertiary amines and quinolines where only hydrogen gas and/or water are formed as the by-product(s). The mechanism is believed to involve the formation of a manganese(III) alkoxide complex which degrades into the aldehyde and a manganese(III) hydride species. The latter reacts with the alcohol to form hydrogen gas and thereby regenerates the alkoxide complex.
- Azizi, Kobra,Akrami, Sedigheh,Madsen, Robert
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p. 6439 - 6446
(2019/04/26)
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- Cobalt complex, preparation method thereof, and application thereof in selective catalysis of transfer hydrogenation reaction of cyano group
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The invention discloses a cobalt complex, a preparation method thereof, and an application thereof in the selective catalysis of a transfer hydrogenation reaction of a cyano group. The structural formula of the cobalt complex is represented by formula I. The cobalt complex is prepared through a reaction of a cobalt salt and an NNP ligand or a PNP ligand under the protection of an inert atmosphere;and the chemical formula of the cobalt salt is CoX12, wherein X1 represents halogen, a sulfate radical, a perchlorate radical, a hexafluorophosphate radical, a hexafluoroantimonate radical, a tetrafluoroborate radical, a trifluoromethanesulfonate radical or a tetra(pentafluorophenyl)borate radical. The cobalt complex can be used in the selective catalysis of the transfer hydrogenation reaction ofthe cyano group to obtain a primary amine compound, a secondary amine compound and a tertiary amine compound, the primary amine compound, the secondary amine compound and the tertiary amine compoundare important intermediates in a series of subsequent functionalizing reactions, and the cobalt complex has a very high catalysis activity, and has great research values and a great application prospect.
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Paragraph 0123-0127; 0130; 0131; 0150-0155
(2018/05/07)
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- Manganese catalyzed reductive amination of aldehydes using hydrogen as a reductant
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A one-pot two-step procedure was developed for the alkylation of amines via reductive amination of aldehydes using molecular dihydrogen as a reductant in the presence of a manganese pyridinyl-phosphine complex as a pre-catalyst. After the initial condensation step, the reduction of imines formed in situ is performed under mild conditions (50-100 °C) with 2 mol% of catalyst and 5 mol% of tBuOK under 50 bar of hydrogen. Excellent yields (>90%) were obtained for a large combination of aldehydes and amines (40 examples), including aliphatic aldehydes and amino-alcohols.
- Wei, Duo,Bruneau-Voisine, Antoine,Valyaev, Dmitry A.,Lugan, No?l,Sortais, Jean-Baptiste
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p. 4302 - 4305
(2018/05/03)
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- A highly active worm-like PtMo nanowire for the selective synthesis of dibenzylamines
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Worm-like nanowires are among the most active nanomaterials. In this study, we report the synthesis of dibenzylamine (DBA) motifs from reductive amination of either aldehydes or nitriles catalyzed by entirely new worm-like PtMo nanowires (PtMo WNWs). Under the assistance of H2 gas, PtMo WNWs can be prepared in a facile manner, following which, their structure and composition are characterized by TEM, XRD, XPS, etc. Upon careful optimization of reaction parameters, the as-prepared PtMo WNWs work effectively in the activation of dihydrogen molecules, and both aldehydes and nitriles can be used as starting materials to fabricate DBAs under mild and green conditions. The reaction kinetics has been investigated, which reveals that the PtMo WNWs show superior activity in the conversion of imines into amines. This study provides a practical advancement in the preparation of amines. Moreover, the protocol reported herein is feasible for the synthesis of worm-like nanostructures with designed composition for various catalytic applications.
- Lu, Shuanglong,Xu, Pengyao,Cao, Xueqin,Gu, Hongwei
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p. 8755 - 8760
(2018/03/08)
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- Ruthenium nanoparticle catalyzed selective reductive amination of imine with aldehyde to access tertiary amines
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Reductive amination is one of the most frequently used transformations in organic synthesis. Herein, we developed a novel ruthenium nanoparticle embedded ordered mesoporous carbon catalyst (Ru-OMC) and a new hydrosilylation process for the synthesis of tertiary amines. We present a direct reductive amination of imines (CN bond) with aldehydes (CO bond) using hydrosilane as the reducing reagent under mild conditions. Moreover, the Ru-OMC catalysts can be reused for up to 14 runs without noticeably losing activity.
- Li, Bin,Liu, Shun,Lin, Qiao,Shao, Yan,Peng, Shiyong,Li, Yibiao
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supporting information
p. 9214 - 9217
(2018/08/23)
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- Triazolylidene-Iridium Complexes with a Pendant Pyridyl Group for Cooperative Metal–Ligand Induced Catalytic Dehydrogenation of Amines
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Two iridium(III) complexes containing a C,N-bidentate pyridyl-triazolylidene ligand were prepared that are structurally very similar but differ in their pendant substituent. Whereas complex 1 contains a non-coordinating pyridyl unit, complex 2 has a phenyl group on the triazolylidene substituent. The presence of the basic pyridyl unit has distinct effects on the catalytic activity of the complex in the oxidative dehydrogenation of benzylic amines, inducing generally higher rates, higher selectivity towards formation of imines versus secondary amines, and notable quantities of tertiary amines when compared to the phenyl-functionalized analogue. The role of the pyridyl functionality has been elucidated from a set of stoichiometric experiments, which demonstrate hydrogen bonding between the pendant pyridyl unit and the amine protons of the substrate. Such Npyr???H?N interactions are demonstrated by X-ray diffraction analysis, 1H NMR, and IR spectroscopy, and suggest a pathway of substrate bond-activation that involves concerted substrate binding through the Lewis acidic iridium center and the Lewis basic pyridyl site appended to the triazolylidene ligand, in agreement with ligand–metal cooperative substrate activation.
- Valencia, Marta,Pereira, Ana,Müller-Bunz, Helge,Belderraín, Tomás R.,Pérez, Pedro J.,Albrecht, Martin
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supporting information
p. 8901 - 8911
(2017/07/11)
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- Colloid and nanosized catalysts in organic synthesis: XVI.1 Continuous hydrogenation of carbonitriles catalyzed by nickel nanoparticles applied on a support
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Conversion of the starting nitriles and selectivity of the products formation during continuous hydrogenation of various nitriles catalyzed by Ni0/Ceokar-2 have been studied as functions of temperature. Performing the process at temperature 120–260°С has led to the formation of a mixture of products containing di- and trialkylamines as well as the corresponding imines and enamines.
- Popov, Yu. V.,Mokhov,Latyshova,Nebykov,Panov,Pletneva, M. Yu.
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p. 2276 - 2281
(2017/11/24)
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- General Reductive Amination of Aldehydes and Ketones with Amines and Nitroaromatics under H2 by Recyclable Iridium Catalysts
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Heterogeneous iridium catalysts were prepared and applied for the reductive amination of aldehydes and ketones with nitroaromatics and amines using H2. The iridium catalysts were prepared by pyrolysis of ionic liquid 1-methyl-3-cyanomethylimidazoulium chloride ([MCNI]Cl) with iridium chloride (IrCl3) in activated carbons. Iridium particles were well dispersed and stable in the N-doped carbon materials from [MCNI]Cl with activated carbon. The Ir@NC(600-2h) catalyst was found to be highly active and selective for the reductive amination of aldehydes and ketones using H2 and a variety of nitrobenzenes and amines were selectively converted into the corresponding secondary and tertiary amines. The Ir@NC(600-2h) catalyst can be reusable several times without evident deactivation.
- Sui, Dejun,Mao, Fei,Fan, Haipeng,Qi, Zhengliang,Huang, Jun
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supporting information
p. 1371 - 137
(2017/10/05)
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- Deoxygenation of tertiary amine N-oxides under metal free condition using phenylboronic acid
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A simple and efficient method for the deoxygenation of amine N-oxides to corresponding amines is reported using the green and economical reagent phenylboronic acid. Deoxygenation of N,N-dialkylaniline N-oxides, trialkylamine N-oxides and pyridine N-oxides were achieved in good to excellent yields. The reduction susceptible functional groups such as ketone, amide, ester and nitro groups are well tolerated with phenylboronic acid during the deoxygenation process even at high temperature. In addition, an indirect method for identification and quantification of tert-amine N-oxide is demonstrated using UV–Vis spectrometry which may be useful for drug metabolism studies.
- Gupta, Surabhi,Sureshbabu, Popuri,Singh, Adesh Kumar,Sabiah, Shahulhameed,Kandasamy, Jeyakumar
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supporting information
p. 909 - 913
(2017/02/15)
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- A Manganese Pre-Catalyst: Mild Reduction of Amides, Ketones, Aldehydes, and Esters
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A new (N-phosphinoamidinate)manganese complex is shown to be a useful pre-catalyst for the hydrosilative reduction of carbonyl compounds, and in most cases at room temperature. The Mn-catalyzed reduction of tertiary amides to tertiary amines, with a useful scope, is demonstrated for the first time by use of this catalyst, and is competitive with the most effective transition-metal catalysts known for such transformations. Ketones, aldehydes, and esters were also successfully reduced under mild conditions by using this new Mn catalyst.
- Kelly, Colin M.,McDonald, Robert,Sydora, Orson L.,Stradiotto, Mark,Turculet, Laura
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supporting information
p. 15901 - 15904
(2017/12/13)
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- Efficient and Selective Hydrosilylation of Secondary and Tertiary Amides Catalyzed by an Iridium(III) Metallacycle: Development and Mechanistic Investigation
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Readily accessible cationic IrIII metallacycles catalyze efficiently the chemoselective hydrosilylation of tertiary and secondary amides to amines. The catalyst described herein operates at low loadings using inexpensive 1,1,3,3-tetramethyldisiloxane and allows fast reactions with high yields, selectivities, and turnover numbers. A transient iminium intermediate has been observed for the first time by using mass spectrometry, and the activation of the catalyst and the silane reagent have been studied by using DFT calculations. These fundamental insights support the present and future improvements of IrIII metallacycles through proper ligand modifications and enable further broad applications of catalysts based on metallacycles.
- Corre, Yann,Trivelli, Xavier,Capet, Frédéric,Djukic, Jean-Pierre,Agbossou-Niedercorn, Francine,Michon, Christophe
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p. 2009 - 2017
(2017/06/13)
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- Nickel-Catalyzed Reduction of Secondary and Tertiary Amides
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The nickel-catalyzed reduction of secondary and tertiary amides to give amine products is reported. The transformation is tolerant of extensive variation with respect to the amide substrate, proceeds in the presence of esters and epimerizable stereocenters, and can be used to achieve the reduction of lactams. Moreover, this methodology provides a simple tactic for accessing medicinally relevant α-deuterated amines.
- Simmons, Bryan J.,Hoffmann, Marie,Hwang, Jaeyeon,Jackl, Moritz K.,Garg, Neil K.
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supporting information
p. 1910 - 1913
(2017/04/11)
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- Ruthenium-catalyzed deaminative redistribution of primary and secondary amines
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A ruthenium-hydride complex, [Ru(H)(Cl)(CO)(PCy3)2], was found to be active in the highly selective redistribution of primary and secondary amines bearing an α-hydrogen atom. This new deaminative coupling of amines enables the highly selective synthesis of secondary amines from primary amines and of tertiary amines from secondary amines with the evolution of ammonia. A preliminary mechanistic view of this novel reaction based on catalytic experiments using NMR methods confirms the synthetic observations.
- Kostera,Wyrzykiewicz,Pawlu?,Marciniec
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supporting information
p. 11552 - 11555
(2017/09/18)
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- Oxidation-Reduction Condensation of Diazaphosphites for Carbon-Heteroatom Bond Formation Based on Mitsunobu Mechanism
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An efficient oxidation-reduction condensation reaction of diazaphosphites with various nonacidic pronucleophiles in the presence of DIAD as a weak oxidant has been developed for carbon-heteroatom bond formation. This mild process affords structurally diverse tertiary amines, secondary amines, esters, ethers, and thioethers in moderate to excellent yields. The selective synthesis of secondary amines from primary amines has been achieved. Importantly, a practical application to the synthesis of antiparkinsonian agent piribedil has been demonstrated.
- Huang, Hai,Kang, Jun Yong
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p. 544 - 547
(2017/02/10)
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- Mitsunobu Reaction Using Basic Amines as Pronucleophiles
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A novel protocol for extending the scope of the Mitsunobu reaction to include amine nucleophiles to form C-N bonds through the utilization of N-heterocyclic phosphine-butane (NHP-butane) has been developed. Both aliphatic alcohols and benzyl alcohols are suitable substrates for C-N bond construction. Various acidic nucleophiles such as benzoic acids, phenols, thiophenol, and secondary sulfonamide also provide the desired products of esters, ethers, thioether, and tertiary sulfonamide with 43-93% yields. Importantly, C-N bond-containing pharmaceuticals, Piribedil and Cinnarizine, have been synthesized in one step from the commercial amines under this Mitsunobu reaction system.
- Huang, Hai,Kang, Jun Yong
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p. 6604 - 6614
(2017/07/15)
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- An improved and one-pot procedure to the synthesis of symmetric amines by domino reactions of 5-methyl-1,3,4-thiadiazole-2-amine, a new nitrogen atom donor, and alkyl halides
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Abstract: A new one-pot method has been introduced in this work for the synthesis of symmetrical primary, secondary, and tertiary alkyl amines from alkyl halides and 5-methyl-1,3,4-thiadiazole-2-amine as a nitrogen-transfer reagent. In this method, all three types of amines have been successfully prepared after changing the ratio of substrates and base control. In addition to the introduction of a new nitrogen-transfer reagent, other important features of this work include normal atmospheric conditions and excellent yields under mild reaction conditions.
- Soleiman-Beigi, Mohammad,Mohammadi, Fariba
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p. 2123 - 2128
(2017/10/26)
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- Expanding Water/Base Tolerant Frustrated Lewis Pair Chemistry to Alkylamines Enables Broad Scope Reductive Aminations
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Lower Lewis acidity boranes demonstrate greater tolerance to combinations of water/strong Br?nsted bases than B(C6F5)3, this enables Si?H bond activation by a frustrated Lewis pair (FLP) mechanism to proceed in the presence of H2O/alkylamines. Specifically, BPh3has improved water tolerance in the presence of alkylamines as the Br?nsted acidic adduct H2O–BPh3does not undergo irreversible deprotonation with aliphatic amines in contrast to H2O–B(C6F5)3. Therefore BPh3is a catalyst for the reductive amination of aldehydes and ketones with alkylamines using silanes as reductants. A range of amines inaccessible using B(C6F5)3as catalyst, were accessible by reductive amination catalysed by BPh3via an operationally simple methodology requiring no purification of BPh3or reagents/solvent. BPh3has a complementary reductive amination scope to B(C6F5)3with the former not an effective catalyst for the reductive amination of arylamines, while the latter is not an effective catalyst for the reductive amination of alkylamines. This disparity is due to the different pKavalues of the water–borane adducts and the greater susceptibility of BPh3species towards protodeboronation. An understanding of the deactivation processes occurring using B(C6F5)3and BPh3as reductive amination catalysts led to the identification of a third triarylborane, B(3,5-Cl2C6H3)3, that has a broader substrate scope being able to catalyse the reductive amination of both aryl and alkyl amines with carbonyls.
- Fasano, Valerio,Ingleson, Michael J.
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supporting information
p. 2217 - 2224
(2017/02/18)
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- REACTIONS OF STANNYL CATIONS
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The present invention relates to a method of reducing, cleaving and/or coupling at least one C=O, C-O, C=C or C=N bond of a compound, using a reagent comprising a stannyl cation.
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Page/Page column 22
(2018/01/17)
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- “One pot” synthesis of tertiary amines: Ru(II) catalyzed direct reductive N-benzylation of imines with benzyl bromide derivatives
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The direct reductive N-benzylation of imines by reaction with benzyl bromide derivatives, in the presence of [RuCl2(p-cymene)]2catalyst and PhSiH3, is performed under mild conditions without additional base. This reaction proceeds by a tandem imine hydrosilylation/nucleophilic substitution with benzyl bromide derivatives to result the tertiary amines.
- Li, Bin,Yu, Jinghao,Li, Caihua,Li, Yibiao,Luo, Jianli,Shao, Yan
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supporting information
p. 137 - 141
(2016/12/26)
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- Simple Metal-Free Direct Reductive Amination Using Hydrosilatrane to Form Secondary and Tertiary Amines
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This work describes the use of cheap, safe, and easy-to-handle hydrosilatrane as the reductant in direct reductive amination reactions. This efficient method enables a facile, metal-free access to secondary and tertiary amines from a wide range of aldehydes and ketones, with the synthesis of tertiary amines requiring no additives at all. This reaction demonstrates excellent functional group tolerance, chemoselectivity, and scalability. (Figure presented.).
- Varjosaari, Sami E.,Skrypai, Vladislav,Suating, Paolo,Hurley, Joseph J. M.,Lio, Ashley M. De,Gilbert, Thomas M.,Adler, Marc J.
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supporting information
p. 1872 - 1878
(2017/06/09)
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- A process for preparing amine compound using carbon-supported cobalt-rhodium nanoparticel catalyzed hydrogen-free recuctive amination
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The present invention relates to hydrogen-free reductive amination of an aldehyde and/or ketone and an amine and/or nitroarene using cobalt-rhodium heterometal nanoparticles supported on carbon as a non-homogeneous catalyst. According to the present invention, it is possible to carry out amination under significantly lower pressure as compared to the reductive amination carried out in the presence of a conventional rhodium or ruthenium catalyst. In addition, there is no need for using an additional ligand, acid or base. Further, it is possible to use water generated in a reaction system by a water-gas shift reaction as a hydrogen source with no use of an external hydrogen source, and thus to use a solvent without purification. Thus, it is possible to simplify the reaction procedure. The catalyst system according to the present invention provides a simple method for preparing secondary and tertiary amines from various aldehydes and amines.
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Paragraph 0066; 0068; 0073
(2017/04/25)
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- Mild and Selective Cobalt-Catalyzed Chemodivergent Transfer Hydrogenation of Nitriles
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Herein, we describe a selective cobalt-catalyzed chemodivergent transfer hydrogenation of nitriles to synthesize primary, secondary, and tertiary amines. The solvent effect plays a key role for the selectivity control. The general applicability of this procedure was highlighted by the synthesis of more than 70 amine products bearing various functional groups in high chemoselectivity. Moreover, this mild system achieved >2000 TONs (turnover numbers) for the transfer hydrogenation of nitriles.
- Shao, Zhihui,Fu, Shaomin,Wei, Mufeng,Zhou, Shaolin,Liu, Qiang
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supporting information
p. 14653 - 14657
(2016/11/23)
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- Scalable synthesis of secondary and tertiary amines by heterogeneous Pt-Sn/γ-Al2O3catalyzed N-alkylation of amines with alcohols
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Synthesis of secondary and tertiary amines has been efficiently realized from the N-alkylation of amines with alcohols by means of heterogeneous bimetallic Pt-Sn/γ-Al2O3catalyst (0.5?wt % Pt, molar ratio Pt:Sn?=?1:3) through a borrowing hydrogen strategy. The Pt-Sn/γ-Al2O3catalyst has exhibited very high catalytic activity towards a wide range of amines and alcohols, and can be conveniently recycled without Pt metal leaching. The present protocol was applied for the synthesis of N-phenylbenzylamine in 96% isolated yield from aniline and benzyl alcohol on a 2.1?kg scale of the substrates, demonstrating its potential applicability for higher-order amine synthesis.
- Wu, Kaikai,He, Wei,Sun, Chenglin,Yu, Zhengkun
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supporting information
p. 8516 - 8521
(2016/11/28)
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- A Pd/CeO2 “H2 Pump” for the Direct Amination of Alcohols
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A Pd/CeO2 catalyst with a prominent reversible H2 storage capacity revealed a high activity and selectivity in the direct amination of benzyl alcohol with aniline and ammonia via the borrowing hydrogen mechanism.
- Yan, Zhen,Tomer, Ajay,Perrussel, Gaetan,Ousmane, Mohamad,Katryniok, Benjamin,Dumeignil, Franck,Ponchel, Anne,Liebens, Armin,Pera-Titus, Marc
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p. 3347 - 3352
(2016/11/16)
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- Conversion of benzyl alcohol to benzonitrile over a Cu10.3/SiO2 catalyst
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A Cu10.3/SiO2 catalyst was prepared for the conversion of benzyl alcohol to benzonitrile through amination-dehydrogenation process. The catalyst showed high activity in the reaction, and a yield as high as 98.0% was reached under the optimized conditions. The catalyst was characterized by XRD, TEM-EDX, TG-DSC, N2 adsorption-desorption and IR of absorbed pyridine methods. The characterization results disclosed that the doping of copper created Lewis acid sites in the matrix of SiO2. The doped copper in the fresh catalyst was present in CuO state, which was reduced to elemental Cu by H2 generated in situ in the catalytic run. The characterization results also disclosed that the catalyst deactivation was mainly caused by the carbonaceous deposition on the surface of the catalyst in the catalytic reaction. The experimental results confirmed that most activity of the catalyst can be recovered at 550°C online by blowing air into the reactor. Partial sintering of copper particles took place during the catalytic run, which led to the slight decreases of Lewis acidity and dehydrogenation capacity, therefore, caused deviation of the performance of the regenerated Cu10.3/SiO2 catalyst from that of the fresh one.
- Zhang, Yuecheng,Zhao, Xiaofu,Zhang, Hongyu,Yan, Xiang,Zhao, Jiquan
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- Colloid and nanosized catalysts in organic synthesis: XIV. Reductive amination and amidation of carbonitriles catalyzed by nickel nanoparticles
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Hydrogenation of carbonitriles catalyzed by nickel nanoparticles in the presence of primary amines led to the predominant formation of unsymmetrical secondary amines. In the presence of secondary amines hydrogenation of nitrites provided enamines as main products. Hydrogenation of nitriles in the presence of formamide or acetamide afforded formyl or acetyl derivatives of primary amines.
- Popov, Yu. V.,Mokhov,Shcherbakova
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p. 798 - 805
(2016/06/13)
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- Palladium nanoparticles stabilised by cinchona-based alkaloids in glycerol: Efficient catalysts for surface assisted processes
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Palladium nanoparticles (PdNPs) were synthesised and fully characterised, both in solution and the solid state, using naturally-occurring cinchona-based alkaloids in neat glycerol. These nano-systems were stable under reaction conditions, finding applications in hydrogenation and hydrodehalogenation processes, as a result of their surface-like behaviour. Their reactivity was improved in relation to that involving PdNPs stabilised by phosphines and also by Pd/C as a heterogenous catalyst, mainly in terms of recyclability. In particular, the colloidal palladium catalyst stabilised by quinidine was highly efficient to promote the hydrodechlorination of aromatic compounds under low dihydrogen pressure. These original catalysts found applications in the synthesis of secondary and tertiary amines including N-substituted anilines, by means of one-pot tandem Pd-catalysed methodologies under smooth conditions. In all of these processes, glycerol performed a crucial function as a liquid support for the immobilisation of nanoparticle-based catalysts, allowing both the stabilisation of the nano-catalysts and easy recycling of the catalytic phase.
- Reina,Pradel,Martin,Teuma,Gómez
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p. 93205 - 93216
(2016/10/11)
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