- Scalable continuous flow hydrogenations using Pd/Al2O3-coated rectangular cross-section 3D-printed static mixers
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A novel type of catalytic static mixers with rectangular cross-section coated with Pd/Al2O3 has been developed. The catalytic mixers, produced by additive manufacturing and coated with the metal catalyst, have shown excellent catalytic performance for continuous flow hydrogenation of nitroaromatics. The heterogeneous catalyst is highly stable. No loss of catalytic performance was observed after long periods of activity and ICP-MS measurements determined that essentially no Pd or Al leaches from the reactor. The rectangular cross-section reactor is readily scalable. The process developed has been showcased for the synthesis of the key intermediate of the medicine tizanidine.
- Lebl, René,Zhu, Yutong,Ng, Derrick,Hornung, Christian H.,Cantillo, David,Kappe, C. Oliver
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Read Online
- Efficient and recyclable bimetallic Co–Cu catalysts for selective hydrogenation of halogenated nitroarenes
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Silica supported N-doped carbon layers encapsulating Co–Cu nanoparticles (Co1Cux@CN/SiO2) were prepared by a one-step impregnation of Co(NO3)2·6H2O, Cu(NO3)2·3H2O, urea and glucose, following in situ carbothermal reduction. Effects of Cu contents on the catalytic performance of the Co1Cux@CN/SiO2 catalysts were investigated for selective hydrogenation of p-chloronitrobenzene to p-chloroaniline. The Co1Cu0.30@CN/SiO2 with Cu/Co molar ratio of 0.30:1 presented much higher activity and stability than the monometallic Co@CN/SiO2 catalyst. The addition of Cu into Co1Cux@CN/SiO2 catalysts had favorable effects on the formation of highly active Co–N sites and N-doped carbon layer. The role of the N-doped carbon layer was to protect the Co from oxidation by air, and the Co1Cu0.30@CN/SiO2 could be reused for at least 12 cycles without decrease in catalytic efficiency. Mechanistic and in situ infrared studies revealed that the interaction effect between the Co and Cu atoms made the surface of Co highly electron rich, which decreased adsorption of halogen groups and resulting in the enhanced selectivity during chemoselective hydrogenation of halogenated nitroarenes for a wide scope of substrates.
- Lu, Xionggang,Ren, Jiaan,Sheng, Yao,Wang, Xueguang,Wu, Baoqin,Zou, Xiujing
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- Aluminum Metal-Organic Framework-Ligated Single-Site Nickel(II)-Hydride for Heterogeneous Chemoselective Catalysis
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The development of chemoselective and heterogeneous earth-abundant metal catalysts is essential for environmentally friendly chemical synthesis. We report a highly efficient, chemoselective, and reusable single-site nickel(II) hydride catalyst based on robust and porous aluminum metal-organic frameworks (MOFs) (DUT-5) for hydrogenation of nitro and nitrile compounds to the corresponding amines and hydrogenolysis of aryl ethers under mild conditions. The nickel-hydride catalyst was prepared by the metalation of aluminum hydroxide secondary building units (SBUs) of DUT-5 having the formula of Al(μ2-OH)(bpdc) (bpdc = 4,4′-biphenyldicarboxylate) with NiBr2 followed by a reaction with NaEt3BH. DUT-5-NiH has a broad substrate scope with excellent functional group tolerance in the hydrogenation of aromatic and aliphatic nitro and nitrile compounds under 1 bar H2 and could be recycled and reused at least 10 times. By changing the reaction conditions of the hydrogenation of nitriles, symmetric or unsymmetric secondary amines were also afforded selectively. The experimental and computational studies suggested reversible nitrile coordination to nickel followed by 1,2-insertion of coordinated nitrile into the nickel-hydride bond occurring in the turnover-limiting step. In addition, DUT-5-NiH is also an active catalyst for chemoselective hydrogenolysis of carbon-oxygen bonds in aryl ethers to afford hydrocarbons under atmospheric hydrogen in the absence of any base, which is important for the generation of fuels from biomass. This work highlights the potential of MOF-based single-site earth-abundant metal catalysts for practical and eco-friendly production of chemical feedstocks and biofuels.
- Antil, Neha,Kumar, Ajay,Akhtar, Naved,Newar, Rajashree,Begum, Wahida,Dwivedi, Ashutosh,Manna, Kuntal
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p. 3943 - 3957
(2021/04/12)
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- ARYL HYDROCARBON RECEPTOR ACTIVATORS
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Small molecule AhR ligands are disclosed. The ligands can induce the differentiation of Tr1 cells to suppress pathogenic immune responses without inducing nonspecific immune suppression. Methods of treatment of autoimmune diseases using the AhR ligands are also disclosed.
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Page/Page column 25-26
(2021/02/05)
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- Regioselective Radical Arene Amination for the Concise Synthesis ofortho-Phenylenediamines
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The formation of arene C-N bonds directly from C-H bonds is of great importance and there has been rapid recent development of methods for achieving this through radical mechanisms, often involving reactiveN-centered radicals. A major challenge associated with these advances is that of regiocontrol, with mixtures of regioisomeric products obtained in most protocols, limiting broader utility. We have designed a system that utilizes attractive noncovalent interactions between an anionic substrate and an incoming radical cation in order to guide the latter to the areneorthoposition. The anionic substrate takes the form of a sulfamate-protected aniline and telescoped cleavage of the sulfamate group after amination leads directly toortho-phenylenediamines, key building blocks for a range of medicinally relevant diazoles. Our method can deliver both free amines and monoalkyl amines allowing access to unsymmetrical, selectively monoalkylated benzimidazoles and benzotriazoles. As well as providing concise access to valuableortho-phenylenediamines, this work demonstrates the potential for utilizing noncovalent interactions to control positional selectivity in radical reactions.
- Gillespie, James E.,Morrill, Charlotte,Phipps, Robert J.
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supporting information
p. 9355 - 9360
(2021/07/19)
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- Enhanced catalytic activity of natural hematite-supported ppm levels of Pd in nitroarenes reduction
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In this work, Pd NPs supported on amine-modified natural hematite have been prepared and characterized. Using this simple catalyst, nitroaromatic compounds as a major cause of industrial pollution were reduced to corresponding amines with ppm levels of Pd in the presence of designer surfactant TPGS-750-M and NaBH4 at room temperature in aqueous media. Synergistic effect between hematite and Pd is responsible for the observed enhanced catalytic activity. This catalyst was recycled for at least four times with a small decrease in the activity.
- Gholinejad, Mohammad,Shojafar, Mohammad,Sansano, José M.
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p. 2033 - 2043
(2020/04/07)
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- Immobilization of Au nanoparticles on poly(glycidyl methacrylate)-functionalized magnetic nanoparticles for enhanced catalytic application in the reduction of nitroarenes and Suzuki reaction
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We report a novel strategy for the synthesis of magnetic nanocomposite for highly efficient catalysis. Poly(glycidyl methacrylate) (PGMA) chains were grafted to the surface of magnetic nanoparticles (MNPs) through surface-initiated reversible addition-fragmentation chain transfer polymerization. Then, the oxirane rings in the PGMA chains were opened with 2,6-diamino pyridine (DAP) molecules as ligands to prepare the solid support. Finally, this magnetic nanocomposite was used for the immobilization of gold nanoparticles. Fourier-transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, transmission electron microscopy, scanning electron microscopy, gel permeation chromatography, vibrating sample magnetometry, and atomic absorption spectroscopy were used for characterization of the catalyst. The loading of gold nanoparticles on the solid support was 0.52 mmol/g. The catalytic activity of the prepared catalyst (MNP@PGMA@DAP@Au) was evaluated for the reduction of nitro compounds and C–C coupling reaction in water. The catalyst can be easily recovered and reused seven times without significant loss of catalytic activity.
- Pourjavadi, Ali,Kohestanian, Mohammad,Keshavarzi, Nahid
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- Co/Cu bimetallic ZIF as New heterogeneous catalyst for reduction of nitroarenes and dyes
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Nowadays one of the great challenges is to design new bimetallic catalysts with enhanced catalytic activity, selectivity and recycling properties. In this work, the preparation of new Co/Cu bimetallic Zeolitic Imidazolate Framework (Co-Cu/ZIF) as an efficient catalyst for the reduction of nitro compounds and organic dyes is described. Co-Cu/ZIF was characterized with different techniques such as SEM, TEM, XRD, XPS, TGA, FT-IR and UV–vis absorption indicating formation of entirely uniform cubic particles. Using this catalyst, structurally different aromatic nitro compounds were reduced efficiently to corresponding amines in excellent yields. Kinetic studies revealed that the reduction rates of nitrophenol isomers follow 3-NP > 4-NP > 2-NP order. The catalytic activity of Co-Cu/ZIF was further investigated in the reduction of organic dyes such as methyl orange (MO) and rhodamine B (RhB). This catalyst was recycled for at least ten runs in the reduction of 4-nitrophenol without a noticeable decrease in activity and reused catalyst was characterized.
- Gholinejad, Mohammad,Naghshbandi, Zhwan,Sansano, José M.
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- In Situ Synthesized Silica-Supported Co@N-Doped Carbon as Highly Efficient and Reusable Catalysts for Selective Reduction of Halogenated Nitroaromatics
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Silica-supported Co@N-doped carbon (Co@CN/SiO2) catalysts were first prepared by a one-step impregnation with a mixed solution of cobalt nitrate, glucose and urea, followed by in situ carbonization and reduction. The Co@CN/SiO2 catalysts were investigated for the selective reduction of nitro aromatics to the corresponding anilines using hydrazine hydrate. The Co@CN/SiO2-500 carbonized at 500 °C exhibited the highest catalytic activity and excellent stability without any decay of activity after 6 cycles for the reduction of nitrobenzene. Both metallic Co atoms and Co?N species formed in the Co@CN/SiO2 catalysts were active, but the Co?N species were dominant active sites. The high activities of the Co@CN/SiO2 catalysts were attributed to the synergistic effect between the Co and N atoms, promoting heterolytic cleavage of hydrazine to form H+/H? pairs. Representative examples demonstrated that the Co@CN/SiO2-500 could completely transform various halogen-substituted nitro aromatics to the corresponding halogenated anilines with high TOFs and selectivity of '99.5 percent.
- Sheng, Yao,Wang, Xueguang,Yue, Shengnan,Cheng, Gonglin,Zou, Xiujing,Lu, Xionggang
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p. 4632 - 4641
(2020/07/30)
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- Benzothiazolyl ureas are low micromolar and uncompetitive inhibitors of 17Β-HSD10 with implications to Alzheimer’s disease treatment
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Human 17β-hydroxysteroid dehydrogenase type 10 is a multifunctional protein involved in many enzymatic and structural processes within mitochondria. This enzyme was suggested to be involved in several neurological diseases, e.g., mental retardation, Parkinson’s disease, or Alzheimer’s disease, in which it was shown to interact with the amyloid-beta peptide. We prepared approximately 60 new compounds based on a benzothiazolyl scaffold and evaluated their inhibitory ability and mechanism of action. The most potent inhibitors contained 3-chloro and 4-hydroxy substitution on the phenyl ring moiety, a small substituent at position 6 on the benzothiazole moiety, and the two moieties were connected via a urea linker (4at, 4bb, and 4bg). These compounds exhibited IC50 values of 1–2 μM and showed an uncompetitive mechanism of action with respect to the substrate, acetoacetyl-CoA. These uncompetitive benzothiazolyl inhibitors of 17β-hydroxysteroid dehydrogenase type 10 are promising compounds for potential drugs for neurodegenerative diseases that warrant further research and development.
- Aitken, Laura,Benek, Ondrej,Chribek, Matej,Dolezal, Rafael,Gunn-Moore, Frank,Hrabinova, Martina,Hroch, Lukas,Jun, Daniel,Kralova, Vendula,Kuca, Kamil,Lycka, Antonin,Musilek, Kamil,Prchal, Lukas,Schmidt, Monika,Vinklarova, Lucie,Zemanova, Lucie
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- Palladium Nanoparticles on a Creatine-Modified Bentonite Support: An Efficient and Sustainable Catalyst for Nitroarene Reduction
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Creatine as the nitrogen-rich, green and cheap compound is used for modification of natural bentonite and the resulting material is employed for the stabilization of Palladium nanoparticles having an average diameter of 3 nm. This new material bento-crt@Pd is characterized using different techniques such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), solid state UV-vis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and energy-dispersive X-ray spectroscopy (EDX). This green catalyst promotes efficient reduction of aromatic nitro compounds in aqueous media. By using this catalyst nitroarenes having electron donating as well as electron withdrawing groups were reduced efficiently to their corresponding amines at room temperature. The catalyst can be recycled seven times and the reused catalyst was characterized by TEM and XPS.
- Gholinejad, Mohammad,Rasouli, Zahra,Najera, Carmen,Sansano, José M.
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p. 1122 - 1129
(2019/09/06)
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- Novel cathepsin K inhibitors block osteoclasts in vitro and increase spinal bone density in zebrafish
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Cathepsin K (Cat K) is a predominant cysteine protease and highly potent collagenase expressed in osteoclasts. Cat K inhibitors are anti-resorptive agents to treat osteoporosis. A novel scaffold of cathepsin K inhibitors, exemplified by lead compound 1x, was used as the template for designing and synthesizing a total of 61 derivatives that have not been reported before. An exploratory structure-activity relationship analysis identified the potent Cat K inhibitor A22, which displayed an IC50 value of 0.44 μM against Cat K. A22 was very specific for Cat K and caused a significantly higher in vitro inhibition of the enzyme as compared to that of lead compound 1x. A surface plasmon resonance analysis confirmed in vitro binding of A22 to Cat K. Molecular docking studies indicated several favourable interaction sites for A22 within the active pocket of Cat K. Furthermore, A22 also blocked active osteoclasts in vitro and increased spinal bone density in zebrafish, in which it showed an activity that was higher than that of the marketed therapeutic bone metabolizer etidronate disodium. A22 represents a very promising lead compound for the development of novel antiresorptive agents functioning as orthosteric inhibitors of Cat K.
- Xue, Si-Tu,Wang, Ya-Li,Han, Xiao-Wan,Yi, Hong,Jiang, Wei,Si, Shu-Yi,Guo, Hui-Fang,Li, Zhuo-Rong
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p. 8600 - 8607
(2019/03/21)
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- Synergistic Effects of ppm Levels of Palladium on Natural Clinochlore for Reduction of Nitroarenes
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Augmenting the modified naturally occurring clay clinochlore with ppm amounts of palladium leads to a new and very effective reagent for the reduction of numerous aromatic nitro species. When palladium nanoparticles are supported on pyridyltriazole-modified clinochlore, iron within clinochlore acts synergistically with palladium to catalyze the reduction of a wide variety of nitroarenes at room temperature in aqueous media. Based on E-factor calculations, the catalyst system is found to be in line with green chemistry standards and can be recycled up to five times.
- Gholinejad, Mohammad,Oftadeh, Erfan,Shojafar, Mohammad,Sansano, José M.,Lipshutz, Bruce H.
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p. 4240 - 4248
(2019/09/06)
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- ANDROGEN RECEPTOR ANTAGONISTS
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Compounds that inhibit the androgen receptor, pharmaceutical compositions comprising one or more of the compounds, as well as methods of treating cancer using such compounds are described.
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Paragraph 0297
(2019/08/26)
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- Synthesis and Antifungal Activity of Substituted 2-Aryl Benzimidazoles Derivatives
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Benzimidazole fungicides were among the early systemic fungicides developed and used for controlling a wide variety of plant diseases. During the course of our screening process for active compounds, two 2-aryl benzimidazoles derivatives bearing sulfoxide group (6b and 6c) have been demonstrated to exhibit good inhibition activity against high-resistant isolate of Botrytis cinerea compared with carbendazim, and the inhibition rates are up to 46.67% and 51.11% at the concentration of 10 μg/mL, which might be considered as the active framework for the discovery of novel fungicide to high-resistant isolate of B. cinerea.
- Huang, Daye,Qiu, Fang,Zhang, Zhigang,Shi, Liqiao,Cao, Chunxia,Ke, Shaoyong
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supporting information
p. 2494 - 2498
(2019/08/12)
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- Synthesis of novel 2-(piperazino-1-yl-alkyl)-1H-benzimidazole derivates and assessment of their interactions with the D2 dopamine receptor
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A total of 14 novel arylpiperazines were synthesized, and pharmaco-logically evaluated by measuring their affinities towards the D2 dopamine receptor (DRD2) in a [3H]spiperone competition assay. All the herein described compounds consist of a benzimidazole moiety connected to N-(2-methoxyphenyl)piperazine via linkers of various lengths. Molecular docking analysis and molecular dynamics simulations were performed on the DRD2–arylpiperazine complexes with the objective of exploring the receptor–ligand interactions and properties of the receptor binding site. The recently published crystal structure of DRD2 was used throughout this study. The major finding is that high affinity arylpiperazines must interact with both the orthosteric binding site and the extended binding pocket of DRD2 and therefore should contain a linker of 5 or 6 methylene groups long.
- Penji?evi?, Jelena Z.,Andri?, Deana B.,?ukalovi?, Vladimir B.,Rogli?, Goran M.,?o?ki?, Vuki?,Kosti?-Raja?i?, Sla?ana V.
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p. 925 - 934
(2019/10/14)
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- The Direct Synthesis of Imines, Benzimidazoles and Quinoxalines from Nitroarenes and Carbonyl Compounds by Selective Nitroarene Hydrogenation Employing a Reusable Iron Catalyst
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The “replacement” of noble metals by earth abundant metals is a desirable aim in catalysis and a possible way of conserving rare elements. The “replacement” is especially attractive if novel selectivity patterns are observed permitting the development of novel coupling reactions. Herein, we report on a novel, robust and reusable iron catalyst, which permits the selective hydrogenation of nitroarenes in the presence of hydrogenation-sensitive functional groups. Based on the selectivity pattern observed, the direct iron-catalyzed synthesis of imines and benzimidazoles from nitroarenes and aldehydes becomes feasible. In addition, we introduce the direct synthesis of quinoxalines from nitroarenes and diketones applying our catalyst.
- B?umler, Christoph,Kempe, Rhett
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supporting information
p. 8989 - 8993
(2018/05/30)
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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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- Mechanochemical catalytic transfer hydrogenation of aromatic nitro derivatives
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Mechanochemical ball milling catalytic transfer hydrogenation (CTH) of aromatic nitro compounds using readily available and cheap ammonium formate as the hydrogen source is demonstrated as a simple, facile and clean approach for the synthesis of substituted anilines and selected pharmaceutically relevant compounds. The scope of mechanochemical CTH is broad, as the reduction conditions tolerate various functionalities, for example nitro, amino, hydroxy, carbonyl, amide, urea, amino acid and heterocyclic. The presented methodology was also successfully integrated with other types of chemical reactions previously carried out mechanochemically, such as amide bond formation by coupling amines with acyl chlorides or anhydrides and click-type coupling reactions between amines and iso(thio)cyanates. In this way, we showed that active pharmaceutical ingredients Procainamide and Paracetamol could be synthesized from the respective nitro-precursors on milligram and gram scale in excellent isolated yields.
- Portada, Tomislav,Margeti?, Davor,?trukil, Vjekoslav
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supporting information
(2018/12/11)
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- Preparation of Well-Ordered Mesoporous-Silica-Supported Ruthenium Nanoparticles for Highly Selective Reduction of Functionalized Nitroarenes through Transfer Hydrogenation
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MCM-41-type mesoporous silica (OMS-IL) was prepared by using an ionic liquid (1-hexadecyl-3-methylimidazolium bromide) as a template. The XRD and TEM results demonstrated that OMS-IL was more stable than the MCM-41 material. Ru nanoparticles were supported on OMS-IL (Ru/OMS-IL) by impregnating OMS-IL with a RuCl3 aqueous solution, and the resulting material was used for the selective reduction of nitroarenes. The effects of the components of the catalysts and the reaction conditions on the catalytic behavior of the prepared catalysts were investigated in detail. Ru/OMS-IL exhibited high catalytic activity and chemoselectivity for the reduction of various substituted nitroarenes to the corresponding aromatic amines in ethanol with hydrazine hydrate as a hydrogen donor under mild conditions. The Ru/OMS-IL catalysts were highly stable and could easily be recovered by simple filtration over at least six recycling reactions without any observable loss in catalytic performance.
- Wei, Ning,Zou, Xiujing,Huang, Haigen,Wang, Xueguang,Ding, Weizhong,Lu, Xionggang
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supporting information
p. 209 - 214
(2018/01/26)
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- A 5 - chlorobenzene and triazole high efficient synthesis method
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The invention relates to a 5 - chlorobenzene and triazole high efficient synthesis method, the method comprises the following steps: (1) 2 - nitro - 4 - chloroaniline, water, catalyst of Raney nickel into reaction kettle reaction, crawls the board detected by complete reaction of the material; (2) the complete reaction of the material passes through the filter, and decompression dehydrating, shall be 4 - A [...] phenylenediamine materials and waste water; (3) 4 - [...] phenylenediamine material with sodium nitrite into medium-pressure reactor water, through the exothermic reaction shall be 5 - chlorobenzene and triazole sodium salt aqueous solution; (4) 5 - chlorobenzene and triazole sodium salt aqueous solution adds by drops of sulfuric acid, after [...] dry to obtain 5 - chlorobenzene and three nitrogen zuozuo thick and waste water B; (5) 5 - chlorobenzene and three nitrogen zuozuo thick washed, and dried to obtain the wash water and content ≥ 99% of the finished product 5 - chlorobenzene and triazole; (6) waste water and waste water A B after mixing and washing water, through the negative pressure distillation to obtain distilled water and residue; distilled water to return to the step (1) in the; residue dehydration be content ≥ 96% of the sodium sulfate by-product. The invention has low cost, low energy consumption and high yield.
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Paragraph 0011-0012; 0017-0018; 0023-0024
(2018/08/28)
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- Potent, Selective, and Cell Active Protein Arginine Methyltransferase 5 (PRMT5) Inhibitor Developed by Structure-Based Virtual Screening and Hit Optimization
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PRMT5 plays important roles in diverse cellular processes and is upregulated in several human malignancies. Besides, PRMT5 has been validated as an anticancer target in mantle cell lymphoma. In this study, we found a potent and selective PRMT5 inhibitor by performing structure-based virtual screening and hit optimization. The identified compound 17 (IC50 = 0.33 μM) exhibited a broad selectivity against a panel of other methyltransferases. The direct binding of 17 to PRMT5 was validated by surface plasmon resonance experiments, with a Kd of 0.987 μM. Kinetic experiments indicated that 17 was a SAM competitive inhibitor other than the substrate. In addition, 17 showed selective antiproliferative effects against MV4-11 cells, and further studies indicated that the mechanism of cellular antitumor activity was due to the inhibition of PRMT5 mediated SmD3 methylation. 17 may represent a promising lead compound to understand more about PRMT5 and potentially assist the development of treatments for leukemia indications.
- Mao, Ruifeng,Shao, Jingwei,Zhu, Kongkai,Zhang, Yuanyuan,Ding, Hong,Zhang, Chenhua,Shi, Zhe,Jiang, Hualiang,Sun, Dequn,Duan, Wenhu,Luo, Cheng
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p. 6289 - 6304
(2017/08/02)
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- Preparation and characterization of copper chloride supported on citric acid-modified magnetite nanoparticles (Cu2+-CA@Fe3O4) and evaluation of its catalytic activity in the reduction of nitroarene compounds
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A new, powerful and recyclable copper catalyst were prepared by heterogenization of copper chloride using of Fe3O4 nano particles modified with citric acid as a linker. This system can catalyze reduction of nitroaren compound to aniline derivatives in the presence of Sodium borohydride as a reduction agent in moderate to good yields. In addition, easy separation and recoverable with an external permanent magnet is the dominant properties of this catalyst (Cu2+-CA@Fe3O4).
- Ghonchepour, Ehsan,Yazdani, Elahe,Saberi, Dariush,Arefi, Marzban,Heydari, Akbar
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- Palladium nanoparticles stabilized by aqueous vesicles self-assembled from a PEGylated surfactant ionic liquid for the chemoselective reduction of nitroarenes
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Vesicles self-assembled from an aqueous PEGylated surfactant ionic liquid solution can be applied for stabilizing palladium nanoparticles, which prove to be an efficient catalytic system for chemoselective hydrogen transfer of nitroarenes using hydrazine hydrate as a hydrogen source. The particle sizes of vesicles are decreased with the increase of ionic liquid's concentrations and relatively small particle sizes are beneficial to the reduction. Moreover, the aqueous catalytic system still stays in reactor by simple extraction, and is reused without further treatment.
- Xu, Zhu-bing,Lu, Guo-ping,Cai, Chun
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- Water as a hydrogen source in palladium-catalyzed reduction and reductive amination of nitroarenes mediated by diboronic acid
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An unprecedented palladium-catalyzed chemoselective reduction and reductive amination of nitroarenes with water as a hydrogen source mediated by diboronic acid have been discovered. A series of aryl amines containing various reducible functional groups were obtained in good to excellent yields.
- Zhou, Yanmei,Zhou, Haifeng,Liu, Sensheng,Pi, Danwei,Shen, Guanshuo
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p. 3898 - 3904
(2017/06/13)
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- Highly chemoselective reduction of nitroarenes over non-noble metal nickel-molybdenum oxide catalysts
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The chemoselective reduction of nitroarenes is an important transformation for the production of arylamines, which are the primary intermediates in the synthesis of pharmaceuticals, agrochemicals and dyes. Heterogeneous non-noble metal nickel-molybdenum oxide catalysts supported on ordered mesoporous silica SBA-15 (Ni-MoO3/CN@SBA-15) were prepared for the first time by treating SBA-15-supported nickel-molybdenum oxide materials with 1,10-phenanthroline, and exhibited unprecedented catalytic activity and chemoselectivity for the reduction of various substituted nitroarenes to the corresponding aromatic amines in ethanol with hydrazine hydrate as a hydrogen donor under mild conditions owing to the synergistic effect of metal Ni and MoO3 species, affording excellent yields of >99% within very short reaction periods (≤60 min). The Ni-MoO3/CN@SBA-15 catalysts were highly stable and could easily be recovered by simple filtration or by an external magnetic field for at least ten recycling reactions without any observable loss of catalytic performance or leaching of metal components.
- Huang, Haigen,Wang, Xueguang,Li, Xu,Chen, Chenju,Zou, Xiujing,Ding, Weizhong,Lu, Xionggang
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p. 809 - 815
(2017/08/15)
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- High Performance and Active Sites of a Ceria-Supported Palladium Catalyst for Solvent-Free Chemoselective Hydrogenation of Nitroarenes
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Cerium oxide-supported palladium catalysts (Pd/CeO2) prepared by a simple impregnation method exhibit exciting catalytic activity and high chemoselectivity for the solvent-free hydrogenation of a variety of substituted nitroarenes including the reducible functional groups to the corresponding aromatic amines under mild reaction conditions. Taking nitrobenzene as an example, the Pd/CeO2 catalyst can afford aniline yields of >99 % with turnover frequencies as high as 11 411 h?1 and 69 824 h?1 at 40 °C and 100 °C, respectively. Pd2+ ion species exist as isolated single atoms with ?Pd2+?O2??Ce4+? linkages on the surface of PdxCe1?xO2?σ solid solution and are found to be active sites for the selective hydrogenation of nitroarenes in the absence of solvent. The superior catalytic performance can be attributed to the cooperative effect between Pd2+ ions and unique surface sites of CeO2. A possible mechanism is proposed for the hydrogenation of nitroarenes with H2 over the Pd/CeO2. The Pd/CeO2 catalyst can be recovered easily and reused for at least seven recycling reactions without loss of catalytic properties.
- Shi, Xiuxiu,Wang, Xueguang,Shang, Xingfu,Zou, Xiujing,Ding, Weizhong,Lu, Xionggang
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p. 3743 - 3751
(2017/10/16)
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- 1,2,4-triazole derivative containing chlorobenzopyrazine structure and preparation method and application thereof
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The invention discloses a 1,2,4-triazole derivative containing a chlorobenzopyrazine structure and a preparation method and an application thereof. The 1,2,4-triazole derivative is prepared by the steps: adopting 4-chloro-2-nitroaniline and hydrazine hydrate to generate a compound (II); then carrying out a reaction of the compound (II) with MBF, to obtain a product (III); chloridizing the compound (III) with POCl3 to obtain a product (IV); carrying out a reaction of the compound (IV) and hydrazine hydrate to obtain an intermediate product (V); and carrying out a reaction of the compound (V) with a substituted acid compound with POCl3 as a solvent, to obtain the 1,2,4-triazole derivative containing the chlorobenzopyrazine structure and represented by the formula (I). The raw materials are simple and easily available, the preparation method is simple, the postprocessing is convenient, the product yield is high, and the compound has weeding activity, has good weeding effect on bentgrass and lettuce weeds, and provides the foundation for research and development of new pesticides.
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Paragraph 0026
(2017/08/27)
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- Application of hydrazone compound with chlorine-containing quinoxaline structure as bactericide
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The invention discloses an application of a hydrazone compound with a chlorine-containing quinoxaline structure as a bactericide. According to the application, a compound 1 is prepared from 5-chloro-o-nitroaniline and hydrazine hydrate; a compound 2 is prepared from the compound 1 and BMF; a compound 3 is prepared through subjecting the compound 2 to a reaction with phosphorus oxychloride; a compound 4 is prepared through subjecting the compound 3 to a reaction with hydrazine hydrate; and a compound (I) is prepared through subjecting the compound 4 to a reaction with a substituted aldehyde compound. According to the application, the raw materials are simple and readily-available, the preparation method is simple, the aftertreatment is convenient, and the product yield is high; and the compound has antifungal activity and particularly has a good bactericidal effect on Colletotrichum acutata, Colletotrichum fragaliae and Colletotrichum gloeosporioides, thereby providing a foundation for the research and development of novel pesticides.
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Paragraph 0030
(2017/04/27)
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- Hydrazone compound containing chlorobenzopyrazine and preparation method and application thereof
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The invention discloses a hydrazone compound containing chlorobenzopyrazine and a preparation method and application thereof. The preparation method comprises the following steps: carrying out a reaction between 5-chloro-o-nitroaniline and hydrazine hydrate to prepare a compound 1; carrying out a reaction between the compound 1 and BMF to prepare a compound 2; carrying out a reaction between the compound 2 and phosphorus oxychloride to prepare a compound 3; carrying out a reaction between the compound 3 and hydrazine hydrate to prepare a compound 4; and carrying out a reaction between the compound 4 and a substituted aldehyde compound to prepare a compound (I). The raw materials are simple and easily available. The preparation method is simple. Postprocessing is convenient. Product yield is high. In addition, the compound has a certain herbicidal activity, especially has a certain weeding effect on Agrostis palustris and lettuce, and provides a basis for research and development of new pesticides.
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Paragraph 0014; 0027
(2017/08/25)
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- Carbon nitride supported palladium nanoparticles: An active system for the reduction of aromatic nitro-compounds
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Synthesis of carbon nitride supported highly dispersed ultrafine palladium nanoparticles has been reported for the reduction of aromatic nitro-compounds using hydrazine hydrate as a reducing agent. As a demonstration, the as-synthesized carbon nitride-palladium composite was shown to be a highly active and chemo-selective for the title reaction. Utilizing the optimized reaction conditions a set of aromatic nitro compounds have been converted to their corresponding amine derivatives with good to excellent yield ranging from 80% to 99%. The catalyst can be used for multiple times without affecting the catalytic performance and can also be stored for a long time at ambient condition maintaining the high catalytic efficiency.
- Nandi, Debkumar,Siwal, Samarjeet,Choudhary, Meenakshi,Mallick, Kaushik
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- Solvent-Free Selective Hydrogenation of Nitroarenes Using Nanoclusters of Palladium Supported on Nitrogen-Doped Ordered Mesoporous Carbon
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The selective hydrogenation of nitroarenes is a key transformation for the production of aromatic amines, which are primary intermediates in the synthesis of pharmaceuticals, agrochemicals, and dyes. However, most reaction processes require toxic organic solvents and suffer from poor selectivity in the presence of other reducible groups. Herein, we report a successful example of nanoclusters of ultrafine Pd supported on N-modified ordered mesoporous CMK-3 carbon (Pd/N-CMK-3) prepared by a facile two-step impregnation route with aqueous solutions of 1,10-phenanthroline and H2PdCl4 that hydrogenated various nitroarenes highly efficiently and selectively to the corresponding aromatic amines with hydrogen in the absence of solvent. The Pd/N-CMK-3 catalyst could be recovered easily for multiple recycling reactions without a loss of catalytic performance.
- Huang, Haigen,Wang, Xueguang,Tan, Mingwu,Chen, Chenju,Zou, Xiujing,Ding, Weizhong,Lu, Xionggang
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p. 1485 - 1489
(2016/05/02)
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- Chemoselective transfer hydrogenation of nitroarenes by highly dispersed Ni-Co BMNPs
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Highly dispread Ni-Co bimetallic nanoparticles (Ni-Co BMNPs) are synthesized and applied as an efficient catalyst in the chemoselective transfer hydrogenation of nitroarenes (CTH) using hydrazine hydrate as the hydrogen donor. The BMNPs can efficiently catalyze the reduction reaction without any additives under mild conditions with high TOF. Significantly higher activity is achieved when compared with corresponding single-component catalysts, optimal composition of the Ni-Co BMNPs was screened which was proved to be crucial in both the selectivity and yields. Excellent performance of Ni-Co BMNPs can be ascribed to the improved dispersion of active sites on the BMNPs surface (compared with Ni NPs) and the electron transfer from cobalt to nickel.
- Zhang, Jia-Wei,Lu, Guo-Ping,Cai, Chun
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- Robust and economic reduction protocol employing immensely stable and leach-proof magnetically separable nanocomposites
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Magnetically recoverable nanocomposites i.e. metal loaded over modified ferrite nanoparticles have been synthesized via a facile three step pathway. Modification of ferrite nanoparticles which serve as the core has been achieved using dopamine hydrogen chloride. Owing to this, introduction of terminal amine groups on the surface of ferrite nanoparticles takes place which provides binding sites for the stabilization of metal nanoparticles providing leach-proof nanocomposites. The synthesized nanocomposites have been characterized using various characterization techniques. Substantiation of the modification of the pristine magnetic ferrite nano particles has been done from the emergence of strong stretching vibration bands of N-H and O-H in the range of 3200-3400 cm-1, N-H stretching band in the range of 1630-1650 cm-1, C-C vibrations of the benzene ring in the range of 1480-1500 cm-1 and C-O stretching vibrations in the range of 1070-1100 cm-1. In the XRD patterns additional peaks corresponding to loaded metals (Cu and Ag) along with peaks corresponding to spinel ferrites have been observed confirming the successful formation of the composite. EDS patterns and FE-SEM elemental mapping confirmed the purity of the samples by displaying the absence of any impurity. Elemental mapping also confirmed the uniform binding of the loaded metals over the surface of modified ferrite nanoparticles. Catalytic efficiency of the synthesized nanocomposites has been explored for the reduction of nitroarenes. Both the Cu and Ag loaded samples exhibited excellent activity and efficient recyclability for the reduction of nitroarenes in the presence of NaBH4 as a reducing agent.
- Goyal, Ankita,Singhal, Sonal
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p. 91275 - 91294
(2016/10/11)
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- Application of 1,2,4-triazole derivatives containing chlorobenzopyrazine structure as bactericide
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The invention discloses an application of 1,2,4-triazole derivatives containing a chlorobenzopyrazine structure as a bactericide. The derivatives are prepared by the following steps: reacting 4-chloro-ortho-nitroaniline with hydrazine hydrate to generate a compound (II), reacting the compound (II) with MBF to obtain a product (III), chlorinating the compound (III) by POCl3 to obtain a product (IV), reacting the compound (IV) with hydrazine hydrate to obtain an intermediate product (V), reacting the compound (V) with substituted acid compounds in a POCl3 solvent to obtain the 1,2,4-triazole derivatives with a chlorobenzopyrazine structure represented by the formula (I). The raw materials are easily available, the preparation method is simple, the post treatment is convenient, the product yield is high, moreover, the compounds have a bacterial killing activity, the control effect on colletotrichum acutatum, strawberry colletotrichum, and wolfberry colletotrichum is especially good, and the derivatives can be used to develop novel pesticides.
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Paragraph 0016; 0028
(2017/06/08)
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- Encapsulation of Pd(II) into superparamagnetic nanoparticles grafted with EDTA and their catalytic activity towards reduction of nitroarenes and Suzuki-Miyaura coupling
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A robust, safe and magnetically recoverable palladium catalyst was synthesized by anchoring Pd(II) onto ethylenediaminetetraacetic acid-coated Fe3O4 (Fe3O4@EDTA) magnetic nanoparticles. The Fe3O4 magnetic nanoparticle-supported Pd(II)-EDTA complex catalyst thus obtained was characterized using scanning and transmission electron microscopies, thermogravimetric analysis, vibrating sample magnetometry, X-ray diffraction, and inductively coupled plasma atomic emission and Fourier transform infrared spectroscopies. Fe3O4@EDTA-Pd(II) was screened for the Suzuki reaction and reduction of nitro compounds in water. The Pd content of the catalyst was measured to be 0.28 mmol Pd g-1. In addition, the Fe3O4@EDTA-Pd catalyst can be easily separated and recovered with an external permanent magnet. The anchored solid catalyst can be recycled efficiently and reused five times with only a very slight loss of catalytic activity.
- Azizi, Kobra,Ghonchepour, Ehsan,Karimi, Meghdad,Heydari, Akbar
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p. 187 - 194
(2015/03/30)
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- Magnetically separable core-shell iron oxide@nickel nanoparticles as high-performance recyclable catalysts for chemoselective reduction of nitroaromatics
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A magnetically separable core-shell iron oxide@nickel (IO@Ni) nanocatalyst was synthesized by reduction of Ni2+ ions in the presence of iron oxide (Fe2+, Fe3+) by a simple one-pot synthetic route using NaBH4 as a reducing agent and starch as a capping agent. The synthesized nanoparticles (NPs) were characterized by several techniques such as X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), selected area electron diffraction (SAED), and energy dispersive X-ray spectroscopy (EDS). The core-shell iron oxide@nickel nanoparticles (IO@NiNPs) were found to have excellent activity for the hydrogenation reactions of aromatic nitro compounds under mild conditions using water as a green solvent. Excellent chemoselectivity and recyclability up to 30 cycles for the nitro group reduction was demonstrated.
- Rathore, Puran Singh,Patidar, Rajesh,Shripathi,Thakore, Sonal
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p. 286 - 295
(2015/02/02)
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- Facile protocol for reduction of nitroarenes using magnetically recoverable CoM0.2Fe1.8O4 (M = Co, Ni, Cu and Zn) ferrite nanocatalysts
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Transition metal doped cobalt ferrite (CoM0.2Fe1.8O4 (M = Co, Ni, Cu, Zn)) nanoparticles were fabricated using the sol-gel methodology. The obtained ferrite nanoparticles were annealed at 400 °C and characterized using Fourier transform infra-red spectroscopy (FT-IR), X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), vibrating sample magnetometry (VSM) and energy dispersive X-ray (EDX) and scanning transmission electron microscopy (STEM). In the FT-IR spectra two bands in the range 1000-400 cm-1 were observed corresponding to the M-O bond in the tetrahedral and octahedral sites. XRD patterns confirmed the formation of a cubic spinel structure with a Fd3m space-group. HR-TEM analysis revealed a quasi-spherical shape with particle sizes in the range 20-30 nm for all the synthesized ferrite nanoparticles. The lattice inter-planar distances of 0.29, 0.25, 0.21 and 0.16 nm obtained from HR-TEM corresponding to the (2 2 0), (3 1 1), (4 0 0) and (5 1 1) lattice planes respectively were in complete agreement with the XRD data. The EDX-STEM confirmed the elemental composition as per the desired stoichiometric ratio. The catalytic efficiency of the synthesized ferrite samples was explored for the reduction of nitrophenols. Cu substituted cobalt ferrite nanoparticles (CoCu0.2Fe1.8O4) possessed excellent catalytic activity while CoM0.2Fe1.8O4 (M = Co, Ni and Zn) were inactive for the same. The substrate scope of the developed protocol was also evaluated for the reduction of various CH3-, NH2-, Br-, Cl- etc. substituted nitroaromatic compounds.
- Goyal, Ankita,Kapoor, Surbhi,Samuel, Pankaj,Kumar, Vinod,Singhal, Sonal
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p. 51347 - 51363
(2015/06/25)
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- Acid-catalyzed hydrolysis of 5-substituted-1H,3H-2,1,3-benzothiadiazole 2,2-dioxides (5-substituted benzosulfamides): Kinetic behavior and mechanistic interpretations
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The acid-catalyzed hydrolysis of a series of 5-substituted-1H,3H-2,1,3-benzothiadiazole 2,2-dioxides has been investigated in aqueous solutions of sulfuric, perchloric, and hydrochloric acid at 85.0 ± 0.05 °C. Analysis of the kinetic data by the excess acidity method, Arrhenius parameters, the order of the catalytic effects of strong acids, the kinetic deuterium isotope effect, and the substituent effect have indicated that the hydrolysis of 5-substituted benzosulfamides 1a, 1b, 1c, 1d occur with a mechanistic switchover from A2 to A1 in the studied range: an A2 mechanism in low acidity regions and an A1 mechanism in high acid concentrations.
- Gediz Erturk, Aliye,Bekdemir, Yunus
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supporting information
p. 358 - 364
(2015/05/05)
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- Selective reduction of halogenated nitroarenes with hydrazine hydrate in the presence of Pd/C
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A large variety of halogenated nitroarenes have been selectively reduced with hydrazine hydrate in the presence of Pd/C to give the corresponding (halogenated) anilines in good yield.
- Li, Fang,Frett, Brendan,Li, Hong-Yu
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p. 1403 - 1408
(2014/06/23)
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- A hydroquinone based palladium catalyst for room temperature nitro reduction in water
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A hydroquinone based palladium complex [Pd(H2L)(Cl)2] (1), acts as an efficient room temperature catalyst for reduction of nitroarenes in water as solvent. 1 also acts as a tandem catalyst for Suzuki-Miyaura cross coupling in ethanol followed by reduction of nitroarenes in one pot with a loading of 0.25 mol% catalyst.
- Kumar, Alok,Purkait, Kallol,Dey, Suman Kr.,Sarkar, Amrita,Mukherjee, Arindam
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p. 35233 - 35237
(2014/11/08)
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- Nickel nanoparticles as efficient catalyst for electron transfer reactions
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The catalytic efficiency of nickel nanoparticles was investigated in some electron transfer reactions. The nanoparticles brought about rapid roomtemperature reduction of a number of nitro aromatics in an aqueous medium with high chemoselectivity and also helped to speed up redox reaction of Fe(CN)-36and S2O-23. In addition, interesting results were obtained for microwave assisted decolourization of azo dye. The reactions were monitored through UV-Vis spectroscopy. The present study has additional advantages of reusability of catalysts and aqueous medium. The ultimate goal was to assess the suitability of low cost nanocatalyst for electron transfer reactions under aqueous conditions. Springer Science+Business Media New York 2013.
- Rathore, Puran Singh,Patidar, Rajesh,Rathore, Sonika,Thakore, Sonal
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p. 439 - 446
(2014/06/24)
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- Synthesis and biological evaluation of 5-substituted derivatives of benzimidazole
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A series of eight novel 5-substituted derivatives of benzimidazole was synthesized by condensation of the corresponding diamine with ethyl 4-[4- -(2-chlorophenyl)piperazin-1-yl]butanoate in refluxing 4 M hydrochloric acid. In vitro antibacterial activity against ten strains, namely Bacillus subtilis, Clostridium sporogenes, Streptosporangium longisporum, Micrococcus flavus, Sarcina lutea, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella enteritidis and Proteus vulgaris and antifungal activity against two fungal strains, namely Candida albicans and Saccharomyces cerevisiae, were evaluated. Of all the compounds screened for activity, 2-{3-[4-(2-chlorophenyl) piperazin-1-yl]propyl}-5-iodo-1H-benzimidazole and 2-{3-[4-(2-chlorophenyl) piperazin-1-yl]propyl}-5-methyl-1H-benzimidazole were associated with higher antifungal activity than commercial drugs.
- Vasic, Vesna P.,Penjisevic, Jelena Z.,Novakovic, Irena T.,Sukalovic, Vladimir V.,Andric, Deana B.,Kostic-Rajacic, Sladana V.
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p. 277 - 282
(2014/04/17)
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- Synthesis of riboflavines, quinoxalinones and benzodiazepines through chemoselective flow based hydrogenations
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Robust chemical routes towards valuable bioactive entities such as riboflavines, quinoxalinones and benzodiazepines are described. These make use of modern flow hydrogenation protocols enabling the chemoselective reduction of nitro group containing building blocks in order to rapidly generate the desired amine intermediates in situ. In order to exploit the benefits of continuous processing the individual steps were transformed into a telescoped flow process delivering selected benzodiazepine products on scales of 50 mmol and 120 mmol respectively.
- Baumann, Marcus,Baxendale, Ian R.,Hornung, Christian H.,Ley, Steven V.,Rojo, Maria Victoria,Roper, Kimberley A.
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p. 9736 - 9759
(2014/08/05)
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- Hydrazine-mediated reduction of nitro and azide functionalities catalyzed by highly active and reusable magnetic iron oxide nanocrystals
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Iron oxide (Fe3O4) nanocrystals generated in situ from an inexpensive and readily available iron source catalyze the reduction of nitroarenes to anilines with unparalleled efficiency. The procedure is chemoselective, avoids the use of precious metals, and can be applied under mild reflux conditions (65 or 80 C) or using sealed vessel microwave heating in an elevated temperature regime (150 C). Utilizing microwave conditions, a variety of functionalized anilines have been prepared in nearly quantitative yields within 2-8 min at 150 C, in a procedure also successfully applied to the reduction of aliphatic nitro compounds and azides. The iron oxide nanoparticles are generated in a colloidal form, resulting in homogeneous solutions suitable for continuous flow processing. Selected examples of anilines of industrial importance have been prepared in a continuous regime using this protocol.
- Cantillo, David,Moghaddam, Mojtaba Mirhosseini,Kappe, C. Oliver
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p. 4530 - 4542
(2013/06/05)
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- Identification of novel HDAC inhibitors through cell based screening and their evaluation as potential anticancer agents
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A series of benzimidazole based HDAC inhibitors have been rationally designed, synthesized and screened. The SAR of this new chemotype is described. The lead compound, 11e, showed strong activity in several cellular assays and demonstrated in vivo efficacy in mouse xenograft pancreatic cancer models.
- Wang, Tong,Sepulveda, Mario,Gonzales, Paul,Gately, Stephen
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p. 4790 - 4793
(2013/09/02)
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- Synthesis of novel histamine H4 receptor antagonists
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This letter describes the discovery and synthesis of a series of octahydropyrrolo[3,4-c]pyrrole based selective histamine hH4 receptor antagonists. The amidine compound 20 was found to be a potent and selective histamine H4 receptor antagonist with moderate clearance and a high volume of distribution.
- Lane, Charlotte A.L.,Hay, Duncan,Mowbray, Charles E.,Paradowski, Michael,Selby, Matthew D.,Swain, Nigel A.,Williams, David H.
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scheme or table
p. 1156 - 1159
(2012/03/11)
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- Encapsulation of silver nanoparticles into graphite grafted with hyperbranched poly(amidoamine) dendrimer and their catalytic activity towards reduction of nitro aromatics
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Hyperbranched polyamidoamine (PAMAM) dendrimer have been successfully grafted on the graphite surface and silver nanoparticles (AgNPs) were readily synthesized within the graphite grafted PAMAM dendrimer templates and applied as nanocatalysts in the reduction of nitro aromatics. Three generations of PAMAM dendrimers with varying chain branches have been utilized in order to serve this purpose. The grafting of PAMAM dendrimer on graphite surface has been monitored using TGA, Raman and FT-IR spectra and the AgNPs/GR-G1.0PAMAM, AgNPs/GR-G2.0PAMAM, AgNPs/GR-G3.0PAMAM nanocatalysts were characterized using XRD, UV-visible spectra, SEM, TEM and EDX spectral analysis. The prepared catalysts were found to exhibit enhanced catalytic activity towards the reduction of 4-nitrophenol and the reaction rate constant for our third generation catalyst was estimated to be 21.7 × 10-3 s-1, which is the highest reported heterogeneous system so far. The efficiency of the system has been further demonstrated through the reduction of halonitroarenes without dehalogenation in the halo-substituted nitro benzenes and reduction of nitro groups in the presence of imine functionalities under mild condition.
- Rajesh, Rajendiran,Venkatesan, Rengarajan
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scheme or table
p. 88 - 96
(2012/07/14)
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- IMIDAZOLE DERIVATIVES
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Described herein are compounds of formula (I), The compounds of formula I act as DGAT1 inhibitors and can be useful in preventing, treating or acting as a remedial agent for hyperlipidemia, diabetes mellitus and obesity.
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Page/Page column 83-84
(2013/02/27)
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- Discovery of a 1,5-dihydrobenzo[b][1,4]diazepine-2,4-dione series of inhibitors of HIV-1 capsid assembly
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The discovery of a 1,5-dihydrobenzo[b][1,4]diazepine-2,4-dione series of inhibitors of HIV-1 capsid assembly is described. Synthesis of analogs of the 1,5-dihydrobenzo[b][1,4]diazepine-2,4-dione hit established structure-activity relationships. Replacement of the enamine functionality of the hit series with either an imidazole or a pyrazole ring led to compounds that inhibited both capsid assembly and reverse transcriptase. Optimization of the bicyclic benzodiazepine scaffold to include a 3-phenyl substituent led to lead compound 48, a pure capsid assembly inhibitor with improved antiviral activity.
- Fader, Lee D.,Bethell, Richard,Bonneau, Pierre,B?s, Michael,Bousquet, Yves,Cordingley, Michael G.,Coulombe, René,Deroy, Patrick,Faucher, Anne-Marie,Gagnon, Alexandre,Goudreau, Nathalie,Grand-Ma?tre, Chantal,Guse, Ingrid,Hucke, Oliver,Kawai, Stephen H.,Lacoste, Jean-Eric,Landry, Serge,Lemke, Christopher T.,Malenfant, Eric,Mason, Stephen,Morin, Sébastien,O'Meara, Jeff,Simoneau, Bruno,Titolo, Steve,Yoakim, Christiane
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scheme or table
p. 398 - 404
(2011/03/17)
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