- The Reactions of NH(a1Δ) with Ethane, Propane, and Isobutane in the Liquid Phase
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The photolysis of HN3 was studied in liquid ethane, propane, and isobutane at the temperature of Dry Ice-methanol.In the reaction mixtures, quaternary ammonium salts were formed between the basic products and HN3.The products were analyzed after having been passed through a trap containing NaOH, in which the salts were decomposed.The main products observed were nitrogen and amines: ethylamine from ethane, propyl- and isopropylamine from propane, and i-butyl, and t-butylamine from an isobutane solution.Ammonia and hydrogen were also formed as minor products.Possible reaction mechanisms are discussed.It is suggested that about 80percent of the singlet NH is inserted into the C-H bond of paraffin to form amine and that 20percent of it is deactivated to the ground triplet state by the reactions with paraffin.The relative efficiencies of the insertion into primary, secondary, and tertiary C-H bonds were estimated to be 1.0, 1.9, and 2.3 respectively.
- Tsunashima, Shigeru,Hamada, Jun-ichi,Hotta, Mitsuhiro,Sato, Shin
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- Thermodynamic Study of the Solvation States of Acid and Base in a Protic Ionic Liquid, Ethylammonium Nitrate, and Its Aqueous Mixtures
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Ethylammonium nitrate (EAN) is a typical protic ionic liquid (PIL) known for a long time. In order to investigate acidbase reaction mechanisms in PIL, thermodynamic quantities of a reaction, which corresponds to autoprotolysis in amphoteric solvents, has been determined in neat EAN. Unlike H3O + and OH- in water, proton donor and acceptor species in EAN are both neutral; this makes acid-base reaction mechanisms in EAN distinct from that in water. EAN-water mixtures have also been studied.
- Kanzaki, Ryo,Song, Xuedan,Umebayashi, Yasuhiro,Ishiguro, Shin-Ichi
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- Mesoporous Ni-B amorphous alloy microspheres with tunable chamber structure and enhanced hydrogenation activity
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A novel co-templating approach involving syringe-squeezing and surfactant assembly was developed to prepare mesoporous amorphous alloy catalysts with tunable chambers and enhanced hydrogenation activity and selectivity.
- Li, Hui,Zhang, Dieqing,Li, Guisheng,Xu, Ye,Lu, Yunfeng,Li, Hexing
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- Fluorescence signaling of Zr4+ by hydrogen peroxide assisted selective desulfurization of thioamide
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Thioamide derivative with a pyrene fluorophore was smoothly transformed to its corresponding amide by Zr4+ ions in the presence of hydrogen peroxide. The transformation was evidenced by 1H NMR spectroscopy and the signaling was completed within 10 min after sample preparation. Interference from Ag+ and Hg2+ ions in Zr 4+-selective fluorescence signaling was readily suppressed with the use of Sn2+ as a reducing additive. Discrimination of Zr4+ from closely related hafnium, which is a frequent contaminant in commercial zirconium, was not possible. Prominent Zr4+-selective turn-on type fluorescence signaling was possible with a detection limit of 4.6 × 10-6 M in an aqueous 99% ethanol solution.
- Hwang, Jiyoung,Choi, Myung Gil,Eor, Suyoung,Chang, Suk-Kyu
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- Characteristics of Si-Y mixed oxide supported nickel catalysts for the reductive amination of ethanol to ethylamines
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Si-Y mixed oxide synthesis was achieved via Si dissolution from a Pyrex reactor during the synthesis of yttrium hydroxide by the precipitation method at pH 10 and an aging temperature of 100 ℃. The Ni/SY mixed oxide catalysts with 5–25 wt% Ni contents were synthesized using an incipient wetness impregnation method. The characterization of the calcined Ni/SY oxide catalysts was performed using N2-sorption, X-ray diffraction, H2-temperature programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), and ethanol-TPD. The reaction parameters such as reaction temperature and the partial pressures of ethanol, NH3, and H2 were varied in the reductive amination reaction, and the catalytic activities for the production of monoethylamine, diethylamine, triethylamine, and acetonitrile as main products were compared. The 10 wt% Ni/SY oxide catalyst containing 11 wt% Si showed the maximum activity, and the presence and absence of H2 and NH3 had a great effect on the conversion and selectivities. The stability after 110 h on stream was observed to be 2.5% less than the initial activity. The cause of this deactivation is the formation of nickel carbonitride, as confirmed by XPS and temperature programmed oxidation (TPO) measurements. On the basis of a detailed proposed reaction mechanism, reaction rates were determined, and the kinetic parameters were estimated by fitting the experimental data obtained under a variety of conditions. Our kinetic model showed that the temperature and the partial pressures of ethanol and hydrogen significantly influenced the conversion, whereas the partial pressure of ammonia had little influence because the imine partial pressure rapidly reached saturation.
- Jeong, Ye-Seul,Woo, Yesol,Park, Myung-June,Shin, Chae-Ho
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p. 287 - 297
(2019/10/14)
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- MOF-Derived Cu-Nanoparticle Embedded in Porous Carbon for the Efficient Hydrogenation of Nitroaromatic Compounds
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Abstract: Novel Cu-nanoparticles (NPs) embedded in porous carbon materials (Cu@C-x) were prepared by one-pot pyrolysis of metal–organic frameworks (MOF) HKUST-1 at different temperatures. The obtained material Cu@C-x was used as a cost-effective catalyst for the hydrogenation of nitrobenzene using NaBH4 as the reducing agent under mild reaction conditions. By considering the catalyst preparation and the catalytic activity, a pyrolysis temperature of 400?°C was finally chosen to synthesize the optimal catalyst. When the aromatic nitro compounds with reducible groups, such as cyano, halogen, and alkyl groups, were tested in this catalytic hydrogenation, an excellent selectivity approaching 100% was achieved. In the recycling experiment, a significant decrease in nitrobenzene conversion was observed in the third cycle, mainly due to the very small amount of catalyst employed in the reaction. Hence, the easily prepared and cost-effective Cu@C-400 catalyst fabricated in this study demonstrates potential for the applications in selective reduction of aromatic nitro compounds. Graphic Abstract: The catalyst Cu@C-400 exhibited 100?% conversion and high selectivity for the hydrogenation of industrially relevant nitroarenes.[Figure not available: see fulltext.].
- Qiao, Chenxia,Jia, Wenlan,Zhong, Qiming,Liu, Bingyu,Zhang, Yifu,Meng, Changgong,Tian, Fuping
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p. 3394 - 3401
(2020/05/19)
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- Bench-Stable Cobalt Pre-Catalysts for Mild Hydrosilative Reduction of Tertiary Amides to Amines and Beyond
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The readily synthesized and bench-stable cobalt dichloride complex (dpephos)CoCl2 is employed as a pre-catalyst for a diversity of silane additions to unsaturated organic molecules, including the normally challenging reduction of amides to amines. With regard to hydrosilative reduction of amides even more effective and activator free catalytic systems can be generated from the bench-stable, commercially available Co(acac)2 and Co(OAc)2 with dpephos and PPh3 ligands. These systems operate under mild conditions (100 °C), with many examples of room temperature transformations, presenting a first example of mild cobalt-catalyzed hydrosilylation of amides.
- Nurseiit, Alibek,Janabel, Jaysan,Gudun, Kristina A.,Kassymbek, Aishabibi,Segizbayev, Medet,Seilkhanov, Tulegen M.,Khalimon, Andrey Y.
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p. 790 - 798
(2019/01/09)
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- Method of preparation of ethylamine or acetonitrile by reductive amination of ethanol
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The present invention relates to a catalyst for manufacturing ethylamine and a method for manufacturing the same. More specifically, the present invention relates to: a nickel-supported catalyst for manufacturing ethylamine or acetonitrile which has impregnated nickel on a supporter as a catalyst capable of efficiently manufacturing ethylamine or acetonitrile at a normal pressure or lower by reacting ethanol with ammonia, a method for manufacturing the same, and a method for manufacturing ethylamine using the same.COPYRIGHT KIPO 2019
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Paragraph 0095-0099; 0107; 0144
(2019/06/22)
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- Metal-free nitrogen -doped carbon nanosheets: A catalyst for the direct synthesis of imines under mild conditions
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Herein, a highly stable, porous, multifunctional and metal-free catalyst was developed, which exhibited significant catalytic performance in the oxidation of amines and transfer hydrogenation of nitriles under mild conditions; this could be attributed to the presence of numerous active sites and their outstanding BET surface area. The obtained results showed that most of the yields of imines exceeded 90%, and the cycling performance of the catalyst could be at least seven runs without any decay in the reaction activity, which could be comparable to those of metal catalysts. Subsequently, a kinetic study has demonstrated that the apparent activation energy for the direct synthesis of imines from amines is 67.39 kJ mol-1, which has been performed to testify that the catalytic performances are rational. Via catalyst characterizations and experimental data, graphitic-N has been proven to be the active site of the catalyst. Hence, this study is beneficial to comprehend the mechanism of action of a metal-free N-doped carbon catalyst in the formation of imines.
- Wang, Kaizhi,Jiang, Pengbo,Yang, Ming,Ma, Ping,Qin, Jiaheng,Huang, Xiaokang,Ma, Lei,Li, Rong
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p. 2448 - 2461
(2019/05/17)
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- A ppm level Rh-based composite as an ecofriendly catalyst for transfer hydrogenation of nitriles: Triple guarantee of selectivity for primary amines
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Hydrogenation of nitriles to afford amines under mild conditions is a challenging task with an inexpensive heterogeneous catalyst, and it is even more difficult to obtain primary amines selectively because of the accompanying self-coupling side reactions. An efficient catalytic system was designed as Fe3O4@nSiO2-NH2-RhCu@mSiO2 to prepare primary amines through the transfer hydrogenation of nitrile compounds with economical HCOOH as the hydrogen donor. The loading of rhodium in the catalyst could be at the ppm level, and the TOF reaches 6803 h-1 for Rh. This catalytic system has a wide substrate range including some nitriles that could not proceed in the previous literature. The experimental results demonstrate that the excellent selectivity for primary amines is guaranteed by three tactics, which are the strong active site, the inhibition of side products by the hydrogen source and the special pore structure of the catalyst. In addition, the catalyst could be reused ten times without activity loss through convenient magnetic recovery.
- Liu, Lei,Li, Jifan,Ai, Yongjian,Liu, Yuhong,Xiong, Jialiang,Wang, Hongdong,Qiao, Yijun,Liu, Wenrui,Tan, Shanchao,Feng, Shaofei,Wang, Kunpeng,Sun, Hongbin,Liang, Qionglin
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p. 1390 - 1395
(2019/03/26)
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- Cobalt-based molecular electrocatalysis of nitrile reduction: Evolving sustainability beyond hydrogen
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Two new cobalt bis-iminopyridines, [Co(DDP)(H2O)2](NO3)2 (1, DDP = cis-[1,3-bis(2-pyridinylenamine)] cyclohexane) and [Co(cis-DDOP)(NO3)](NO3) (2, cis-DDOP = cis-3,5-bis[(2-Pyridinyleneamin]-trans-hydroxycyclohexane) electrocatalyse the 4-proton, 4-electron reduction of acetonitrile to ethylamine. For 1, this reduction occurs in preference to reduction of protons to H2. A coordinating hydroxyl proton relay in 2 reduces the yield of ethylamine and biases the catalytic system back towards H2.
- Child, Simon N.,Raychev, Radoslav,Moss, Nathan,Howchen, Benjamin,Horton, Peter N.,Prior, Christopher C.,Oganesyan, Vasily S.,Fielden, John
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p. 9576 - 9580
(2019/07/10)
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- Alkyl coupling in tertiary amines as analog of Guerbet condensation reaction
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We report here that C-C coupling in tertiary amines for the synthesis of long chain and hindered amines might be efficiently performed over Pt and Pd catalysts. The mechanism study confirms similarity with the Guerbet reaction through dehydrogenation of the alkyl group and subsequent attack of the α-carbon atom by an alkyl group of another molecule. Finally, secondary amines and tertiary amines with longer alkyl chains are formed.
- Zhou, Yage,Wu, Dan,Hernández, Willinton Yesid,Ma, Changru,Su, Huangyang,Ordomsky, Vitaly
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p. 9845 - 9849
(2019/04/01)
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- Sustainable hydrogenation of aliphatic acyclic primary amides to primary amines with recyclable heterogeneous ruthenium-tungsten catalysts
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The hydrogenation of amides is a straightforward method to produce (possibly bio-based) amines. However current amide hydrogenation catalysts have only been validated in a rather limited range of toxic solvents and the hydrogenation of aliphatic (acyclic) primary amides has rarely been investigated. Here, we report the use of a new and relatively cheap ruthenium-tungsten bimetallic catalyst in the green and benign solvent cyclopentyl methyl ether (CPME). Besides the effect of the Lewis acid promotor, NH3 partial pressure is identified as the key parameter leading to high primary amine yields. In our model reaction with hexanamide, yields of up to 83% hexylamine could be achieved. Beside the NH3 partial pressure, we investigated the effect of the catalyst support, PGM-Lewis acid ratio, H2 pressure, temperature, solvent tolerance and product stability. Finally, the catalyst was characterized and proven to be very stable and highly suitable for the hydrogenation of a broad range of amides.
- Coeck, Robin,Berden, Sarah,De Vos, Dirk E.
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supporting information
p. 5326 - 5335
(2019/10/11)
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- Organocatalytic Decarboxylation of Amino Acids as a Route to Bio-based Amines and Amides
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Amino acids obtained by fermentation or recovered from protein waste hydrolysates represent an excellent renewable resource for the production of bio-based chemicals. In an attempt to recycle both carbon and nitrogen, we report here on a chemocatalytic, metal-free approach for decarboxylation of amino acids, thereby providing a direct access to primary amines. In the presence of a carbonyl compound the amino acid is temporarily trapped into a Schiff base, from which the elimination of CO2 may proceed more easily. After evaluating different types of aldehydes and ketones on their activity at low catalyst loadings (≤5 mol%), isophorone was identified as powerful organocatalyst under mild conditions. After optimisation many amino acids with a neutral side chain were converted in 28–99 % yield in 2-propanol at 150 °C. When the reaction is performed in DMF, the amine is susceptible to N-formylation. This consecutive reaction is catalysed by the acidity of the amino acid reactant itself. In this way, many amino acids were efficiently transformed to the corresponding formamides in a one-pot catalytic system.
- Claes, Laurens,Janssen, Michiel,De Vos, Dirk E.
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p. 4297 - 4306
(2019/08/26)
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- Chemo-selective reduction of nitro and nitrile compounds using Ni nanoparticles immobilized on hyperbranched polymer-functionalized magnetic nanoparticles
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The nitro and nitrile groups in aromatic and aliphatic compounds containing various reducible substituents such as carboxylic acid, ketone, aldehyde and halogen are selectively reduced to the corresponding amines in water as a green solvent with excellent yields by employing NaBH4 in the presence of Fe3O4@PAMAM/Ni(0)-b-PEG nanocatalyst. The morphology and structural features of the catalyst were characterized using various microscopic and spectroscopic techniques. The designed catalyst system because of it being covered with hydrophilic polymers is soluble in a wide range of solvents (e.g. water and ethanol) and suitable for immobilizing and stabilizing Ni nanoparticles in aqueous mediums. In addition, the catalyst can be easily recovered from a reaction mixture by applying an external magnetic field and can be reused up to six runs without significant loss of activity.
- Tabatabaei Rezaei, Seyed Jamal,Mashhadi Malekzadeh, Asemeh,Poulaei, Sima,Ramazani, Ali,Khorramabadi, Hossein
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- Ethylamine preparation method
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The invention discloses an ethylamine preparation method. The method comprises the following steps that acetonitrile, ammonia borane, a mesoporous compound metal oxide catalyst AB2O4 and a solvent aremixed and then sealed, and reaction is carried out at the reaction pressure of 0.1-0.2 MPa and 20-80 DEG C for 2-12 h; the weight of the mesoporous compound metal oxide catalyst AB2O4 is 1-10% of that of the acetonitrile, and a molar ratio of the ammonia borane to the acetonitrile is (0.6 to 2):1; obtained reaction liquid is distilled to obtain ethylamine. The method has the advantages of efficient reaction process, simple product and high yield.
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Page/Page column 5-6
(2018/11/03)
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- Structural investigation, molecular structure and molecular docking of solifenacin succinate, flavoxate hydrochloride and tolterodine tartrate anti-cholinergic drugs: Correlation using thermal analysis and mass spectral fragmentation
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In this work, solifenacin succinate (SOLS), flavoxate HCl (FLXHC) and tolterodine tartrate (TOLT) drugs were investigated using thermal analysis (TA) measurements in comparison with electron impact mass spectral fragmentation at 70?eV. Also chemical purity, melting point (using differential scanning calorimetry), activation energy and enthalpy in the process of characterizing medicines were important requirements evaluated in quality control of the pharmaceutical industry. The thermal decomposition of these drugs revealed a moderate stability up to 161, 215 and 195?°C for SOLS, FLXHC and TOLT drugs, respectively, before a complete decomposition in the temperature ranges of 161–800, 215–650 and 195–650?°C. The initial decomposition can be accounted for the loss of C7H12NO molecule, followed by loss of C20H20NO5 molecule for SOLS, loss of HCl, followed by loss of C24H25NO4 molecule for FLXHC, and loss of C23H30NO7 molecule followed by loss of C3H7 for TOLT drug. On the other hand, the molecular ion can easily fragmented by succinate, HCl and tartrate loss followed by loss of C2H5, C4H8 and C2H4 for SOLS, FLXHC and TOLT drugs, respectively. This is the best-selected pathway comparable with decomposition using TA. In addition, computational method including molecular docking was carried out to investigate the E. coli bacterial RNA (4p20) binding to the drug compounds under study. Molecular docking calculation indicated the existence of hydrogen bond and π-interaction between active sites of E. coli bacterial RNA (4p20) and O and or N and aromatic ring in all drug compounds which lead to their stabilization.
- Attia, Ali K.,Mohamed, Gehad G.,Ahmed, Heba E.
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p. 1345 - 1360
(2017/09/06)
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- MOF-derived Ni-based nanocomposites as robust catalysts for chemoselective hydrogenation of functionalized nitro compounds
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Porous graphitic carbon layers encapsulating Ni nanoparticles (Ni@C) were prepared by a facile thermolysis of a Ni-containing metal-organic framework, the structure of which were characterized by power X-ray diffraction (XRD), N2 adsorption-desorption, transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) in detail. The resulting Ni@C nanocomposites served as highly efficient and magnetically recyclable catalysts for the hydrogenation of diverse functionalized nitro compounds to the corresponding anilines under relatively milder conditions. The high catalytic performance and the enhanced stability are ascribed to the synergistic effects and electron transfer between the metallic Ni and graphitic carbon as well as the unique encapsulation structure. The achieved success in the MOF-derived Ni@C nanocomposites may pave the way for designing environmentally benign catalytic hydrogenation processes for industrial applications.
- Tang, Bo,Song, Wei-Chao,Yang, En-Cui,Zhao, Xiao-Jun
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p. 1531 - 1539
(2017/01/21)
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- Is water a suitable solvent for the catalytic amination of alcohols?
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The catalytic conversion of biomass and biogenic platform chemicals typically requires the use of solvents. Water is present already in the raw materials and in most cases a suitable solvent for the typically highly polar substrates. Hence, the development of novel catalytic routes for further processing would profit from the optimization of the reaction conditions in the aqueous phase mainly for energetic reasons by avoiding the initial water separation. Herein, we report the amination of biogenic alcohols in aqueous solutions using solid Ru-based catalysts and ammonia as a reactant. The influence of different support materials and bimetallic catalysts is investigated for the amination of isomannide as a biogenic diol. Most importantly, the transferability of the reaction conditions to various other primary and secondary alcohols is successfully proved. Hence, water appears to be a suitable solvent for the sustainable production of biogenic amines and offers great potential for further process development.
- Niemeier, Johannes,Engel, Rebecca V.,Rose, Marcus
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supporting information
p. 2839 - 2845
(2017/07/24)
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- Cobalt-Catalyzed and Lewis Acid-Assisted Nitrile Hydrogenation to Primary Amines: A Combined Effort
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The selective hydrogenation of nitriles to primary amines using a bench-stable cobalt precatalyst under 4 atm of H2 is reported herein. The catalyst precursor was reduced in situ using NaHBEt3, and the resulting Lewis acid formed, BEt3, was found to be integral to the observed catalysis. Mechanistic insights gleaned from para-hydrogen induced polarization (PHIP) transfer NMR studies revealed that the pairwise hydrogenation of nitriles proceeded through a Co(I/III) redox process.
- Tokmic, Kenan,Jackson, Bailey J.,Salazar, Andrea,Woods, Toby J.,Fout, Alison R.
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supporting information
p. 13554 - 13561
(2017/10/05)
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- Sequential Uncaging with Green Light can be Achieved by Fine-Tuning the Structure of a Dicyanocoumarin Chromophore
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We report the synthesis and photochemical properties of a series of dicyanocoumarinylmethyl (DEAdcCM)- and dicyanocoumarinylethyl (DEAdcCE)-based photocages of carboxylic acids and amines with absorption maximum around 500 nm. Photolysis studies with green light have demonstrated that the structure of the coumarin chromophore as well as the nature of the leaving group and the type of bond to be photocleaved (ester or carbamate) have a strong influence on the rate and efficiency of the uncaging process. These experimental observations were also supported by DFT calculations. Such differences in deprotection kinetics have been exploited to sequentially photolyze two dicyanocoumarin-caged model compounds (e.g., benzoic acid and ethylamine), and open the way to increasing the number of functional levels that can be addressed with light in a single system, particularly when combining dicyanocoumarin caging groups with other photocleavable protecting groups, which remain intact under green light irradiation.
- Gandioso, Albert,Palau, Marta,Nin-Hill, Alba,Melnyk, Ivanna,Rovira, Carme,Nonell, Santi,Velasco, Dolores,García-Amorós, Jaume,Marchán, Vicente
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p. 375 - 384
(2017/06/23)
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- Using the hydrogen and oxygen in water directly for hydrogenation reactions and glucose oxidation by photocatalysis
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Direct utilization of the abundant hydrogen and oxygen in water for organic reactions is very attractive and challenging in chemistry. Herein, we report the first work on the utilization of the hydrogen in water for the hydrogenation of various organic compounds to form valuable chemicals and the oxygen for the oxidation of glucose, simultaneously by photocatalysis. It was discovered that various unsaturated compounds could be efficiently hydrogenated with high conversion and selectivity by the hydrogen from water splitting and glucose reforming over Pd/TiO2 under UV irradiation (350 nm). At the same time, glucose was oxidated by the hydroxyl radicals from water splitting and the holes caused by UV irradiation to form biomass-derived chemicals, such as arabinose, erythrose, formic acid, and hydroxyacetic acid. Thus, the hydrogen and oxygen were used ideally. This work presents a new and sustainable strategy for hydrogenation and biomass conversion by using the hydrogen and oxygen in water.
- Zhou, Baowen,Song, Jinliang,Zhou, Huacong,Wu, Tianbin,Han, Buxing
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p. 463 - 468
(2015/12/26)
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- A metal-organic framework-templated synthesis of γ-Fe2O3 nanoparticles encapsulated in porous carbon for efficient and chemoselective hydrogenation of nitro compounds
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The γ-Fe2O3 nanoparticles well dispersed in porous carbon were fabricated via a Fe-based metal-organic framework-templated pyrolysis. The resultant product exhibits excellent catalytic activity, chemoselectivity and magnetic recyclability for the hydrogenation of diverse nitro compounds under mild conditions.
- Li, Yang,Zhou, Yu-Xiao,Ma, Xiao,Jiang, Hai-Long
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supporting information
p. 4199 - 4202
(2016/03/19)
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- A MOF-derived Co-CoO@N-doped porous carbon for efficient tandem catalysis: Dehydrogenation of ammonia borane and hydrogenation of nitro compounds
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The one-step pyrolysis of a zeolite-type metal-organic framework, Co(2-methylimidazole)2 (ZIF-67), produces an N-doped porous carbon incorporating well-dispersed Co/CoO nanoparticles, which exhibit excellent catalytic activity, chemoselectivity and magnetic recyclability for the tandem dehydrogenation of ammonia borane and hydrogenation of nitro compounds at room temperature.
- Ma, Xiao,Zhou, Yu-Xiao,Liu, Hang,Li, Yang,Jiang, Hai-Long
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supporting information
p. 7719 - 7722
(2016/07/06)
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- Graphene-Supported NiPd Alloy Nanoparticles for Effective Catalysis of Tandem Dehydrogenation of Ammonia Borane and Hydrogenation of Nitro/Nitrile Compounds
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Monodisperse NiPd alloy nanoparticles (NPs) are synthesized and assembled on graphene (G) or other support to provide clean, efficient catalysis of tandem reactions—dehydrogenation of ammonia borane (AB) and hydrogenation of R—NO2 and/or R—CN to R—NH2. The tandem reactions proceed quickly and with high efficiency in aqueous methanol solutions at room temperature, and the supported catalyst is readily recovered for re-use, providing a simple, efficient and ‘green’ route to the preparation of many common pharmaceutical, dye or other chemical products. NiPd alloy NPs of 3.4 nanometer size were prepared by co-reduction of nickel(II) acetate and palladium(II) acetlyacetonate by borane-tert-butylamine in oleylamine and deposited on G via a solution phase self-assembly process. The G-NiPd showed composition-dependent catalysis on the tandem reaction with G-Ni30Pd70 being the most active. A variety of R—NO2 and/or R—CN derivatives (R alkyl or aryl) were reduced selectively into R—NH2 via G-Ni30Pd70 catalyzed tandem reaction in short (5-30 minute) reaction times with conversion yields reaching up to 100%, demonstrating a new approach to G-NiPd-catalyzed dehydrogenation of AB and hydrogenation of R—NO2 and R—CN. The G-NiPd NP catalyst is efficient and is reusable; thus the reaction can be performed in an environment-friendly process with short reaction times and high yields.
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Paragraph 0022
(2016/10/17)
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- TG–MS study on the kinetics and mechanism of thermal decomposition of copper ethylamine chromate, a new precursor for copper chromite catalyst
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Copper chromite is a well-known burn rate modifier for the combustion of composite solid propellants. In this study, basic copper ethylamine chromate (CEC), a new precursor for copper chromite catalyst, was synthesized by precipitation method. The thermal decomposition of the precursor was followed by thermogravimetry–mass spectroscopy (TG–MS) and X-ray diffraction techniques and compared with that of copper ammonium chromate, a conventional precursor for copper chromite catalyst. TG–MS analysis for the decomposition of CEC revealed that the decomposition starts with the liberation of ethylamine. The change in enthalpy for the decomposition reaction of copper ethylamine chromate was higher than that of copper ammonium chromate due to the oxidation of ethyl group. The reducing atmosphere created by the presence of carbon during the decomposition of CEC produced a mixture of Cu, CuCr2O4, CuCrO2 and CuO, while the oxidizing atmosphere of copper ammonium chromate produced a mixture of CuCr2O4 and CuO. Mechanistic study based on Criado and Coats–Redfern methods showed that CEC follows random nucleation (F1) mechanism as the rate-determining step for the thermal decomposition process.
- Paulose, Sanoop,Thomas, Deepthi,Jayalatha,Rajeev,George, Benny K.
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p. 1099 - 1108
(2016/07/06)
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- Method for manufacturing ammonia-N
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PROBLEM TO BE SOLVED: To provide a method for producing an N-alkyl hydroxylamine, which produces a pure N-alkyl hydroxylamine in a high yield under a mild condition by a simple method, does not require a strict time management and is advantageous for industrial-scale production. SOLUTION: The method for producing an N-alkyl hydroxylamine includes bringing an N-alkyl nitro compound into contact with a hydrogen source in the presence of a solid catalyst supporting palladium on silica and in the absence of a significant quantity of a fourth reaction component. The method for producing an N-alkyl hydroxylamine includes bringing (A) an N-alkyl nitro compound into contact only with (B) a hydrogen source and (C) a solid catalyst supporting palladium on silica, or bringing (A) an N-alkyl nitro compound into contact only with (B) a hydrogen source, (C) a solid catalyst supporting palladium on silica and (D) a solvent that does not deactivate catalytic activity and has a pKa of ≥12. COPYRIGHT: (C)2012,JPOandINPIT
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Paragraph 0095; 0098
(2018/12/01)
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- Characterization of a novel amine transaminase from Halomonas elongata
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Chiral amines are indispensable building blocks in the production of biologically active compounds. They are fundamental for the pharmaceutical industry, both as active molecules themselves and as chiral auxiliaries in asymmetric synthesis; however, the available synthetic strategies often present disadvantages. ω-Transaminases (ω-TAs) appear as an attractive alternative by driving the stereoselective amination of prochiral ketones. HEWT is a novel amine transaminase from the moderate halophilic bacterium, Halomonas elongata DSM 2581, which is highly (S)-selective, being able to fully convert (S)-1-phenylethylamine to acetophenone and showing no activity with the corresponding (R)-1-phenylethylamine. HEWT has a broad substrate scope, active with a range of amino donors and acceptors, and naturally accepts isopropylamine (IPA) as amino donor in asymmetric synthesis providing a 41% conversion of pyruvate in 24 h at 37°C starting with 1:1 molar ratio between the reagents. HEWT also accepts ortho-xylylenediamine as amino donor in for amine synthesis, in particular, with benzaldehyde yielding high conversions between 90 and 95%. The enzyme is also tolerant to the presence of cosolvents up to 20% making it a promising candidate for industrial applications.
- Cerioli, Lorenzo,Planchestainer, Matteo,Cassidy, Jennifer,Tessaro, Davide,Paradisi, Francesca
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p. 141 - 150
(2015/09/01)
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- One-pot tandem catalysis over Pd@MIL-101: boosting the efficiency of nitro compound hydrogenation by coupling with ammonia borane dehydrogenation
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The hydrogenation efficiency of nitro compounds was found to be greatly boosted by coupling with dehydrogenation of ammonia borane. The Pd@MIL-101 with tiny Pd NPs is exceptionally efficient and recyclable in the tandem reactions and diverse nitro compounds can be selectively reduced to the corresponding amines in 1.5-5 min with quantitative yields.
- Yang, Qihao,Chen, Yu-Zhen,Wang, Zhiyong U.,Xu, Qiang,Jiang, Hai-Long
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p. 10419 - 10422
(2015/06/25)
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- Recyclable aluminium oxy-hydroxide supported Pd nanoparticles for selective hydrogenation of nitro compounds via sodium borohydride hydrolysis
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The reduction of aromatic/aliphatic nitro compounds to primary amines with high yields was easily realized by transfer hydrogenation comprising commercially available aluminium oxy-hydroxide-supported Pd nanoparticles (0.5 wt% Pd, Pd/AlO(OH)) as catalysts and NaBH4 as the hydrogen reservoir at room temperature in a water/methanol mixture (v/v = 7/3). The presented catalytic methodology is highly efficient for the reduction of various nitro compounds as well as reusable. A variety of R-NO2 derivatives were tested by performing the Pd/AlO(OH) catalysed reduction reaction and all the nitro compounds were selectively reduced to their corresponding primary amines in reaction times ranging from 0.75 to 13 min with yields reaching up to 99%. This process can be assessed as an eco-friendly method involving both reusable catalysts (Pd/AlO(OH) NPs) and hydrogen sources (NaBH4).
- G?ksu, Haydar
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p. 8498 - 8504
(2015/11/10)
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- Synthesis of a yolk/shell Fe3O4@poly(ionic liquid)s-derived nitrogen doped graphitic porous carbon materials and its application as support for nickel catalysts
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The synthesis of yolk/shell spheres including a movable magnetic core, a poly(ionic liquid)s-derived porous carbon shell, and nickel nanoparticles confined within the porous shell is reported. The as-prepared carbon shell is graphitic and porous, as proven by X-ray diffraction, Brunauer-Emmett-Teller equation, and transmission electron microscopy characterizations. The ensuing catalyst has been employed for the tandem dehydrogenation of sodium borohydride and hydrogenation of several nitro/nitrile compounds in aqueous media, which resulted in high yields with a very low amount of the catalyst.
- Nabid, Mohammad Reza,Bide, Yasamin,Habibi, Zahra
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p. 2258 - 2265
(2015/02/02)
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- Gold-Catalyzed Reductive Transformation of Nitro Compounds Using Formic Acid: Mild, Efficient, and Versatile
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Developing new efficient catalytic systems to convert abundant and renewable feedstocks into valuable products in a compact, flexible, and target-specific manner is of high importance in modern synthetic chemistry. Here, we describe a versatile set of mild catalytic conditions utilizing a single gold-based solid catalyst that enables the direct and additive-free preparation of four distinct and important amine derivatives (amines, formamides, benzimidazoles, and dimethlyated amines) from readily available formic acid (FA) and nitro starting materials with high level of chemoselectivity. By controlling the stoichiometry of the employed FA, which has attracted considerable interest in the area of sustainable chemistry because of its potential as an entirely renewable hydrogen carrier and as a versatile C1 source, a facile atom- and step-efficient transformation of nitro compounds can be realized in a modular fashion. Renewable formic acid as a flexible feedstock: A versatile heterogeneous gold-based catalytic system has been developed for the controlled, flexible, and target-specific reductive transformation of nitro compounds using stoichiometric equivalents of formic acid as a key starting material under mild and convenient conditions. The overall operational simplicity, high chemoselectivity, functional-group tolerance, and reusability of the catalyst make this approach an attractive and reliable tool for organic and process chemists.
- Yu, Lei,Zhang, Qi,Li, Shu-Shuang,Huang, Jun,Liu, Yong-Mei,He, He-Yong,Cao, Yong
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p. 3029 - 3035
(2015/09/28)
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- Formic acid: A future bridge between the power and chemical industries
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In the future hydrogen economy, formic acid is considered an efficient hydrogen storage molecule and a new C1 building block for the chemical industry. Formic acid could be used as a sustainable carbon monoxide source. In the present work efficient catalysts for the decomposition of formic acid and its derivatives to carbon monoxide have been found. The proposed catalysts are widely available zeolites, making the process feasible for industrial scale applications. Thus, formic acid and its derivatives could be seen as liquid and storable versions of carbon monoxide, which could be directly used in the existing chemical value chain.
- Supronowicz,Ignatyev,Lolli,Wolf,Zhao,Mleczko
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p. 2904 - 2911
(2015/05/27)
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- Insight into the mechanism of hydrogenation of amino acids to amino alcohols catalyzed by a heterogeneous MoOx-modified Rh catalyst
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Hydrogenation of amino acids to amino alcohols is a promising utilization of natural amino acids. We found that MoOx-modified Rh/SiO2 (Rh-MoOx/SiO2) is an efficient heterogeneous catalyst for the reaction at low temperature (323 K) and the addition of a small amount of MoOx drastically increases the activity and selectivity. Here, we report the catalytic potential of Rh-MoOx/SiO2 and the results of kinetic and spectroscopic studies to elucidate the reaction mechanism of Rh-MoOx/SiO2 catalyzed hydrogenation of amino acids to amino alcohols. Rh-MoOx/SiO2 is superior to previously reported catalysts in terms of activity and substrate scope. This reaction proceeds by direct formation of an aldehyde intermediate from the carboxylic acid moiety, which is different from the reported reaction mechanism. This mechanism can be attributed to the reactive hydride species and substrate adsorption caused by MoOx modification of Rh metal, which results in high activity, selectivity, and enantioselectivity.
- Tamura, Masazumi,Tamura, Riku,Takeda, Yasuyuki,Nakagawa, Yoshinao,Tomishige, Keiichi
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p. 3097 - 3107
(2015/02/05)
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- Lamellar Ni/Al-SBA-15 fibers: Preparation, characterization, and applications as highly efficient catalysts for amine and imine syntheses
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A novel Ni/Al-SBA-15 fiber catalyst with a lamellar structure was prepared by the urea precipitation method and successfully utilized in the environmental-friendly reduction of nitro functionality. The applications of the catalyst in highly efficient one-pot amine and imine syntheses were developed; the physicochemical properties of the samples were evaluated with ICP-OES, N2 adsorption, XRD, HRTEM, and EDX. This new catalyst highlights potent catalytic activities and a simple recycling process as an important environmentally-friendly feature.
- Ren, Ren,Ma, Jiantai
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p. 74802 - 74810
(2015/09/21)
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- Tandem dehydrogenation of ammonia borane and hydrogenation of nitro/nitrile compounds catalyzed by graphene-supported NiPd alloy nanoparticles
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We report a facile synthesis of monodisperse NiPd alloy nanoparticles (NPs) and their assembly on graphene (G) to catalyze the tandem dehydrogenation of ammonia borane (AB) and hydrogenation of R-NO2 and/or R-CN to R-NH2 in aqueous methanol solutions at room temperature. The 3.4 nm NiPd alloy NPs were prepared by coreduction of nickel(II) acetate and palladium(II) acetlyacetonate by borane-tert-butylamine in oleylamine and deposition on G via a solution phase self-assembly process. G-NiPd showed composition-dependent catalysis on the tandem reaction with G-Ni 30Pd70 being the most active. A variety of R-NO 2 and/or R-CN derivatives were reduced selectively into R-NH 2 via G-Ni30Pd70 catalyzed tandem reaction in 5-30 min reaction time with the conversion yields reaching up to 100%. Our study demonstrates a new approach to G-NiPd-catalyzed dehydrogenation of AB and hydrogenation of R-NO2 and R-CN. The G-NiPd NP catalyst is efficient and reusable, and the reaction can be performed in an environment-friendly process with short reaction times and high yields.
- Goeksu, Haydar,Ho, Sally Fae,Metin, Oender,Korkmaz, Katip,Mendoza Garcia, Adriana,Gueltekin, Mehmet Serdar,Sun, Shouheng
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p. 1777 - 1782
(2014/06/24)
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- Hydroxylamine as an oxygen nucleophile: Substitution of sulfonamide by a hydroxyl group in benzothiazole-2-sulfonamides
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Benzothiazole-2-sulfonamides react with an excess of hydroxylamine in aqueous solutions to form 2-hydroxybenzothiazole, sulfur dioxide, and the corresponding amine. Mechanistic studies that employ a combination of structure-reactivity relationships, oxygen labeling experiments, and (in)direct detection of intermediates and products reveal that the reaction proceeds via oxygen attack, and that oxygen incorporated in the 2-hydroxybenzothiazole product derives from hydroxylamine. The reaction, which is performed under mild conditions, can be used as a deprotection method for cleavage of benzothiazole-2-sulfonyl-protected amino acids.
- Kamps, Jos J. A. G.,Belle, Roman,Mecinovi?, Jasmin
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supporting information
p. 1103 - 1108
(2013/03/28)
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- Microcalorimetric adsorption and infrared spectroscopic studies of KNi/MgAlO catalysts for the hydrogenation of acetonitrile
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Ni/MgAlO and K2CO3Ni/MgAlO catalysts for the hydrogenation of acetonitrile to primary amine were studied. Microcalorimetric measurements and infrared spectroscopy were used to study the adsorption of CO, H2, acetonitrile,
- Zhao, Jie,Chen, Hui,Tian, Xiaocong,Zang, Han,Fu, Yuchuan,Shen, Jianyi
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p. 161 - 169
(2013/04/10)
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- Reactions of aminyl radicals during radiolysis and photolysis of aqueous solutions of amino alcohols and their derivatives
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It has been found that the radiolysis of the aqueous solutions of a,a-amino alcohols leads to the formation of degradation products of the parent substances. The experimental data suggest that the degradation process includes the stage of the formation of aminyl radicals, which undergo decomposition with the simultaneous cleavage of -C-C- and -O-H bonds through a five-membered transition state. The radiation-induced degradation of amino alcohols is enhanced in an alkaline medium, in which the amino group is deprotonated, and is blocked via the etherification of the hydroxyl group in the parent substances or the introduction of reducing agents. Pleiades Publishing, Ltd., 2012.
- Lisovskaya,Sladkova,Sosnovskaya,Shadyro
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p. 241 - 246
(2012/11/13)
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- A convenient approach to synthesizing peptide C-terminal N-alkyl amides
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Peptide C-terminal N-alkyl amides have gained more attention over the past decade due to their biological properties, including improved pharmacokinetic and pharmacodynamic profiles. However, the synthesis of this type of peptide on solid phase by current available methods can be challenging. Here we report a convenient method to synthesize peptide C-terminal N-alkyl amides using the well-known Fukuyama N-alkylation reaction on a standard resin commonly used for the synthesis of peptide C-terminal primary amides, the peptide amide linker-polyethylene glycol-polystyrene (PAL-PEG-PS) resin. The alkylation and oNBS deprotection were conducted under basic conditions and were therefore compatible with this acid labile resin. The alkylation reaction was very efficient on this resin with a number of different alkyl iodides or bromides, and the synthesis of model enkephalin N-alkyl amide analogs using this method gave consistently high yields and purities, demonstrating the applicability of this methodology. The synthesis of N-alkyl amides was more difficult on a Rink amide resin, especially the coupling of the first amino acid to the N-alkyl amine, resulting in lower yields for loading the first amino acid onto the resin. This method can be widely applied in the synthesis of peptide N-alkyl amides.
- Fang, Wei-Jie,Yakovleva, Tatyana,Aldrich, Jane V.
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p. 715 - 722
(2013/05/09)
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- Kinetics and mechanism of oxidation of N-methylethylamine by bis(hydrogenperiodato)argentate(III) complex anion
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Oxidation of N-methylethylamine by bis(hydrogenperiodato)argentate(III) ([Ag(HIO6)2]5-) in alkaline medium results in demethylation, giving rise to formaldehyde and ethylamine as the oxidation products. The oxidation kinetics has been followed spectrophotometrically in the temperature range of 20.0-35.0 °C, and shows an overall second-order character: being first-order with respect to both Ag(III) and N-methylethylamine. The observed second-order rate constants k′ increase with increasing [OH-] of the reaction medium, but decrease with increasing the total concentration of periodate. An empirical rate expression for k′ has been derived as: k′ = (k a + k b[OH-])K 1/{f([OH-])[IO4 -]tot + K 1}, where k a and k b are rate parameters, and K 1 is an equilibrium constant. These parameters have been evaluated at all the temperatures studied, enabling calculation of activation parameters. A reaction mechanism is suggested to involve two pre-equilibria, leading to formation of an intermediate Ag(III) complex, namely [Ag(HIO6)(OH)(MeNHEt)]2-. In the subsequent rate-determining steps, this intermediate undergoes inner-sphere electron transfer from the coordinated amine to the metal center via two distinct routes, one of which is spontaneous while the other is mediated by a hydroxide ion.
- Guo, Yukun,Shi, Hongmei,Huo, Shuying,Shen, Shigang
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experimental part
p. 59 - 64
(2012/02/02)
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- Reactions of diethylamine and ethylene catalyzed by PtII or Pt0 - Transalkylation vs. hydroamination
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PtBr2/nBu4PBr (without solvent) or K 2PtCl4/NaBr (in water) have been shown to efficiently catalyze the hydroamination of ethylene by aniline and are poor catalysts for the hydroamination of ethylene by diethylamine. A DFT study on the hydroamination mechanism indicates that the energetic span of the C 2H4/Et2NH catalytic cycle is close to that of the C2H4/PhNH2 cycle. The poor performance is attributed to rapid catalyst degradation with reduction to metallic platinum. Pt0, on the other hand, catalyzes a transalkylation process, partially transforming Et2NH into Et3N, EtNH2 and NH3. This process is inhibited by C2H4. Mechanistic considerations for the Pt0-catalyzed transalkylation process are presented. Copyright
- Dub, Pavel A.,Bethegnies, Aurelien,Poli, Rinaldo
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experimental part
p. 5167 - 5172
(2012/02/14)
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- Bimetallic Ru/Ni supported catalysts for the gas phase hydrogenation of acetonitrile
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A family of bimetallic Ni-Ru catalysts supported on a mesoporous SBA-15 silica was prepared by conventional impregnation method, with constant metal molar loadings, but varying Ni/(Ni + Ru) atomic ratios. The corresponding Ni and Ru monometallic catalysts were also prepared for comparison. These catalysts were characterized by XRD, N2 adsorption-desorption at -196 °C, TEM, XPS, H2-TPR, chemisorption of H2 at r.t., H2-TPD and NH3-TPD techniques. Finally, they were also tested in the hydrogenation of acetonitrile reaction, in the gas phase and at atmospheric pressure. Acetonitrile conversion values depended on the Ni/(Ni + Ru) composition of the bimetallic catalysts. Ru-rich bimetallic catalysts exhibited acetonitrile conversion values higher than that of pure Ni one; thus, although selectivity patterns remained almost unchanged, primary amine yields were increased. These higher conversion values resulted as a consequence of enhanced specific activity of Ni0 atoms, attributable to a strong interaction between both metals, Ni and Ru, likely because NiRu alloy nanoparticles were formed.
- Braos-García,García-Sancho,Infantes-Molina,Rodríguez-Castellón,Jiménez-López
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experimental part
p. 132 - 144
(2010/08/07)
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- Selective synthesis of N-Alkyl hydroxylamines by hydrogenation of nitroalkanes using supported palladium catalysts
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The selective hydrogenation of nitroalkanes to the corresponding N-alkyl hydroxylamines is achieved at room temperature with excellent yields (up to 98 %), by using common supported palladium catalysts. The reaction temperature is key to the highly selective formation of the hydroxylamines, which proceeds smoothly in a H2 atmosphere without additives. The catalyst can be recycled up to five times.
- Takenaka, Yasumasa,Kiyosu, Takahiro,Choi, Jun-Chul,Sakakura, Toshiyasu,Yasuda, Hiroyuki
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experimental part
p. 1166 - 1168
(2011/12/02)
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- Selective reduction of nitro compounds using CeY zeolite under microwaves
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Aliphatic and aromatic nitro compounds were selectively reduced to their corresponding amino derivatives in good yields using formic acid and CeY zeolite under monomode reactor. This system is found to be compatible with several sensitive functionalities. Beside the recycling result showed it had a long catalyst lifetime and could maintain activity even after being used for 20 cycles.
- Arya, Kapil,Dandia, Anshu
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experimental part
p. 55 - 58
(2010/09/05)
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- METHOD FOR PRODUCING AMINES FROM GLYCERIN
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The present invention relates to a process for preparing amines by reacting glycerol with hydrogen and an aminating agent from the group of ammonia and primary and secondary amines in the presence of a catalyst at a temperature of from 100° C. to 400° C. and a pressure of from 0.01 to 40 MPa (from 0.1 to 400 bar). Preference is given to using glycerol based on renewable raw materials. The catalyst preferably comprises one metal or a plurality of metals or one or more oxygen compounds of the metals of groups 8 and/or 9 and/or 10 and/or 11 of the Periodic Table of the Elements. The invention further relates to the use of the reaction products as an additive in cement or concrete production and in other fields of use. This invention further provides the compounds 1,2,3-triaminopropane, 2-aminomethyl-6-methylpiperazine, 2,5-bis(aminomethyl)piperazine and 2,6-bis(aminomethyl)piperazine.
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Page/Page column 12
(2010/10/03)
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- Proton donor acceptor interactions of disubstituted thiovioluric acids with amines bases
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The stability constants of hydrogen bonded ion pair or proton transfer complex formation of N,N'-dimethyl thiovioluric acid [DMTVA], N,N'- di-o-tolyl thiovioluric acid [DOTTVA], N,N'-di-m-tolyl thiovioluric acid [DMTTVA] and N,N'-di-p-tolyl thiovioluric acid [DPTTVA] with methyl amine, dimethyl amine, trimethyl amine, ethyl amine, diethyl amine, triethyl amine, n-butyl amine, dibutyl amine and tributyl amine have been determined spectroscopically in 95% (v/v) ethanol. The composition of the complexes is determined in solution potentiometrically and spectrophotometrically and substantiated by the element analysis and IR spectra of the isolated complexes. The stabilities of the thiovioluric acid-amine complexes have been correlated with the base strength of amines. The correlation between the mode of enolization in the acids and the structure of the proton transfer complex is discussed. The variation in proton transfer constants of acids has been explained on the basis of the changes in the distribution of electron density in the ring.
- Singh,Rani, Babita,Deep, Sorabh Singh
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experimental part
p. 4781 - 4786
(2010/12/18)
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- Direct hydrogenation of amides to alcohols and amines under mild conditions
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The selective, direct hydrogenation of amides to the corresponding alcohols and amines with cleavage of the C-N bond was discovered. The expected products of C-O cleavage are not formed (except as traces in the case of anilides). The reaction proceeds under mild pressure and neutral, homogeneous conditions using a dearomatized, bipyridyl-based PNN Ru(II) pincer complex as a catalyst. The postulated mechanism involves metal-ligand cooperation by aromatization- dearomatization of the heteroaromatic pincer core and does not involve hydrolytic cleavage of the amide. The simplicity, generality, and efficiency of this environmentally benign process make it attractive for the direct transformations of amides to alcohols and amines in good to excellent yields.
- Balaraman, Ekambaram,Gnanaprakasam, Boopathy,Shimon, Linda J. W.,Milstein, David
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supporting information; experimental part
p. 16756 - 16758
(2011/02/16)
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- Molecular cloning and characterization of γ-Glutamyltranspeptidase from pseudomonas nitroreducens IFO12694
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y-Glutamyltranspeptidase from Pseudomonas nitroreducens IFO12694 (PnGGT) exhibited higher hydro-lytic activity than transfer activity, as compared with other y-glutamyltranspeptidases (GGTs). PnGGT showed little activity towards most of L-amino acids and towards glycyl-glycine, which is often used as a standard y-glutamyl accepter in GGT transfer reactions. The preferred substrates for PnGGT as a y-glutamyl accepter were amines such as methylamine, ethylamine, and isopropylamine.
- Imaoka, Masashi,Yano, Shigekazu,Okumura, Masashi,Hibi, Takao,Wakayama, Mamoru
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experimental part
p. 1936 - 1939
(2011/06/11)
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- Effect of surface composition on the catalytic performance of molybdenum phosphide catalysts in the hydrogenation of acetonitrile
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A series of molybdenum phosphide catalysts with initial Mo/P ratios varying in a narrow range of 0.90-1.10 was prepared by temperature-programmed reaction; characterized by X-ray diffraction, BET, elemental analysis, X-ray photoelectron spectroscopy, and CO chemisorption measurements; and tested for the hydrogenation of acetonitrile at different pressures (0.1-1.0 MPa) and temperatures (473-513 K). The catalysts exhibited attractive catalytic activity, especially at a H2 pressure above 0.2 MPa. The surface composition of the MoP catalysts could be fine-tuned by the initial Mo/P ratio, which consequently led to different surface properties (e.g., CO uptakes) and catalytic behaviors. Catalysts with high initial Mo amount gave high selectivity to the primary amine, ethylamine, whereas those with high initial P amount created more condensed amines, diethylamine and triethylamine.
- Yang, Pengfei,Jiang, Zongxuan,Ying, Pinliang,Li, Can
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