- A facile reduction procedure for nitroarenes with Cp2TiCl2/Sm system
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Nitroarenes can be reduced to the corresponding primary amines in good yields with Cp2TiCl2/Sm system under mild and neutral conditions.
- Huang, You,Liao, Puhong,Zhang, Yongmin,Wang, Yulu
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- Nickel Boride Catalyzed Reductions of Nitro Compounds and Azides: Nanocellulose-Supported Catalysts in Tandem Reactions
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Nickel boride catalyst prepared in situ from NiCl2 and sodium borohydride allowed, in the presence of an aqueous solution of TEMPO-oxidized nanocellulose (0.01 wt%), the reduction of a wide range of nitroarenes and aliphatic nitro compounds. Here we describe how the modified nanocellulose has a stabilizing effect on the catalyst that enables low loading of the nickel salt pre-catalyst. Ni-B prepared in situ from a methanolic solution was also used to develop a greener and facile reduction of organic azides, offering a substantially lowered catalyst loading with respect to reported methods in the literature. Both aromatic and aliphatic azides were reduced, and the protocol is compatible with a one-pot Boc-protection of the obtained amine yielding the corresponding carbamates. Finally, bacterial crystalline nanocellulose was chosen as a support for the Ni-B catalyst to allow an easy recovery step of the catalyst and its recyclability for new reduction cycles.
- Proietti, Giampiero,Prathap, Kaniraj Jeya,Ye, Xinchen,Olsson, Richard T.,Dinér, Peter
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supporting information
p. 133 - 146
(2021/11/04)
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- Palladium Immobilized on a Polyimide Covalent Organic Framework: An Efficient and Recyclable Heterogeneous Catalyst for the Suzuki–Miyaura Coupling Reaction and Nitroarene Reduction in Water
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An efficient and recyclable Pd nano-catalyst was developed via immobilization of Pd nanoparticles on polyimide linked covalent organic frameworks (PCOFs) that was facilely prepared through condensation of melamine and 3,3′,4,4′-biphenyltetracarboxylic dianhydride. The Pd nanoparticles (Pd NPs) catalyst was thoroughly characterized by FT-IR, XRD, SEM, TEM. Furthermore, the catalytic activity of Pd NPs catalyst was evaluated by Suzuki–Miyaura coupling reaction and nitroarene reduction in water, respectively. The excellent yields of corresponding products revealing revealed that the Pd NPs catalyst could be applied as an efficient and reusable heterogeneous catalyst for above two reactions. Graphical Abstract: [Figure not available: see fulltext.]
- Dong, Zhenhua,Pan, Hongguo,Gao, Pengwei,Xiao, Yongmei,Fan, Lulu,Chen, Jing,Wang, Wentao
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p. 299 - 306
(2021/05/10)
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- Homogeneous catalyst containing Pd in the reduction of aryl azides to primary amines
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Abstract: Commercially available dichloro[2,2′-bis(diphenylphosphino)-1,1′-binaphthyl]palladium(II) (BINAP.PdCl2) homogeneous catalyst was used for the reduction of aryl azides to primary amines. The reactions were carried out in water and yields above 95% were obtained in a short time. Sodium borohydride was used as the reducing reagent. A number of aryl azide derivatives have been converted into primary amines, thanks to the hydrogen gas released by sodium borohydride with the help of water and catalyst. Graphical Abstract: [Figure not available: see fulltext.] Synopsis Commercially available dichloro[2,2′-bis(diphenylphosphino)-1,1′-binaphthyl]palladium(II) (BINAP.PdCl2) homogeneous catalyst was used for the reduction of aryl azides to primary amines. The reactions were carried out in water and yields above 95% were obtained in a short time. Sodium borohydride was used as the reducing reagent. A number of aryl azide derivatives have been converted into primary amines, thanks to the hydrogen gas released by sodium borohydride with the help of water and catalyst.
- Aydinli, E.,Cantopcu, E.,Goksu, H.
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- Electrochemical C-H Halogenations of Enaminones and Electron-Rich Arenes with Sodium Halide (NaX) as Halogen Source for the Synthesis of 3-Halochromones and Haloarenes
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Without employing an external oxidant, the simple synthesis of 3-halochromones and various halogenated electron-rich arenes has been realized with electrode oxidation by employing the simplest sodium halide (NaX, X = Cl, Br, I) as halogen source. This electrochemical method is advantageous for the simple and mild room temperature operation, environmental friendliness as well as broad substrate scope in both C-H bond donor and halogen source components.
- Jin, Jun,Lin, Yan,Liu, Yunyun,Wan, Jie-Ping,Wang, Chaoli
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p. 12378 - 12385
(2021/09/07)
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- Synthesis of 3-nitroindoles by sequential paired electrolysis
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3-Nitroindoles are synthetically versatile intermediates but current methods for the preparation hinder their widespread application. Herein, we report that nitroenamines undergo electrochemical cyclisation to 3-nitroindoles in the presence of potassium iodide. Detailed control experiments and cyclic voltammogram studies infer the reaction proceedsviaa sequential paired electrolysis process, beginning with anodic oxidation of iodide (I?) to the iodine radical (I˙), which facilitates cyclisation of the nitroenamine to give a 3-nitroindolinyl radical. Cathodic reduction and protonation generates a 3-nitroindoline that upon oxidation forms the 3-nitroindole.
- Kilmartin, Paul A.,Lindsay, Ashley C.,Sperry, Jonathan
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p. 7903 - 7913
(2021/09/28)
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- In situcreation of multi-metallic species inside porous silicate materials with tunable catalytic properties
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Porous metal silicate (PMS) material PMS-11, consisting of uniformly distributed multi-metallic species inside the pores, is synthesized by using a discrete multi-metal coordination complex as the template, demonstrating high catalytic activity and selectivity in hydrogenation of halogenated nitrobenzenes by synergistically activating different reactant moleculesviaNi and Co transition metal centers, while GdIIILewis acid sites play a role in tuning the catalytic properties.
- Liu, Yang-Yang,Wu, Chuan-De,Zhan, Guo-Peng
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supporting information
p. 6185 - 6188
(2021/06/30)
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- NaI/PPh3-Mediated Photochemical Reduction and Amination of Nitroarenes
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A mild transition-metal- and photosensitizer-free photoredox system based on the combination of NaI and PPh3 was found to enable highly selective reduction of nitroarenes. This protocol tolerates a broad range of reducible functional groups such as halogen (Cl, Br, and even I), aldehyde, ketone, carboxyl, and cyano. Moreover, the photoredox catalysis with NaI and stoichiometric PPh3 provides also an alternative entry to Cadogan-type reductive amination when o-nitrobiarenes were used.
- Qu, Zhonghua,Chen, Xing,Zhong, Shuai,Deng, Guo-Jun,Huang, Huawen
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supporting information
p. 5349 - 5353
(2021/07/21)
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- Development and Application of Efficient Ag-based Hydrogenation Catalysts Prepared from Rice Husk Waste
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The development of strategies for the sustainable management and valorization of agricultural waste is of outmost importance. With this in mind, we report the use of rice husk (RH) as feedstock for the preparation of heterogeneous catalysts for hydrogenation reactions. The catalysts were prepared by impregnating the milled RH with a silver nitrate solution followed by carbothermal reduction. The composition and morphology of the prepared catalysts were fully assessed by IR, AAS, ICP-MS, XPS, XRD and STEM techniques. This novel bio-genic silver-based catalysts showed excellent activity and remarkable selectivity in the hydrogenation of nitro groups in both aromatic and aliphatic substrates, even in the presence of reactive functionalities like halogens, carbonyls, borate esters or nitriles. Recycling experiments showed that the catalysts can be easily recovered and reused multiple times without significant drop in performance and without requiring re-activation.
- Unglaube, Felix,Kreyenschulte, Carsten Robert,Mejía, Esteban
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p. 2583 - 2591
(2021/04/09)
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- Biorenewable carbon-supported Ru catalyst for: N -alkylation of amines with alcohols and selective hydrogenation of nitroarenes
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Herein, we developed a renewable carbon-supported Ru catalyst (Ru/PNC-700), which was facilely prepared via simple impregnation followed by the pyrolysis process. The prepared Ru/PNC-700 catalyst demonstrated remarkable catalytic activity in terms of conversion and selectivity towards N-alkylation of anilines with benzyl alcohol and chemoselective hydrogenation of aromatic nitro compounds. In addition, local anesthetic pharmaceutical agents (e.g., butamben and benzocaine), including key drug intermediates, were synthesized in excellent yields under mild conditions and in the presence of water as a green solvent. Moreover, the prepared Ru/PNC-700 catalyst could be easily recovered and reused up to five times without any apparent loss in activity and selectivity.
- Goyal, Vishakha,Narani, Anand,Natte, Kishore,Poddar, Mukesh Kumar,Ray, Anjan,Sarki, Naina,Tripathi, Deependra
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p. 14687 - 14694
(2021/08/23)
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- Development of sustainable and efficient nanocatalyst based on polyoxometalate/nickel oxide nanocomposite: A simple and recyclable catalyst for reduction of nitroaromatic compounds
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In this paper, we report the synthesis and characterization of NiO@PolyMo nanocomposite. The newly synthesized nanocomposite was characterized by transmission electronmicroscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), and powder X-ray diffraction (XRD). The particle sizes of the NiO@PolyMo nanocatalyst are in the range of 10–20 nm. Powder XRD patterns show that the phase of NiO@PolyMo remains unaltered even after the functionalization of NiO. The lattice fringes of d = 0.20 nm were observed, which correspond to the (111) plane of NiO phase. The newly synthesized material shows excellent catalytic performance and good selectivity for reduction of nitroarenes. The advantages of the present protocols are mild, and can be carried out using water as a solvent, which is an eco-friendly benign.
- Kurbah, Sunshine Dominic
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p. 1487 - 1495
(2021/04/22)
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- Synthesis, Structure, and Catalytic Hydrogenation Activity of [NO]-Chelate Half-Sandwich Iridium Complexes with Schiff Base Ligands
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A series of N,O-coordinate iridium(III) complexes with a half-sandwich motif bearing Schiff base ligands for catalytic hydrogenation of nitro and carbonyl substrates have been synthesized. All iridium complexes showed efficient catalytic activity for the hydrogenation of ketones, aldehydes, and nitro-containing compounds using clean H2 as reducing reagent. The iridium catalyst displayed the highest TON values of 960 and 950 in the hydrogenation of carbonyl and nitro substrates, respectively. Various types of substrates with different substituted groups afforded corresponding products in excellent yields. All N,O-coordinate iridium(III) complexes 1-4 were well characterized by IR, NMR, HRMS, and elemental analysis. The molecular structure of complex 1 was further characterized by single-crystal X-ray determination.
- Lv, Wen-Rui,Li, Rong-Jian,Liu, Zhen-Jiang,Jin, Yan,Yao, Zi-Jian
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p. 8181 - 8188
(2021/05/26)
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- Cyclic (Alkyl)(amino)carbene Ligand-Promoted Nitro Deoxygenative Hydroboration with Chromium Catalysis: Scope, Mechanism, and Applications
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Transition metal catalysis that utilizes N-heterocyclic carbenes as noninnocent ligands in promoting transformations has not been well studied. We report here a cyclic (alkyl)(amino)carbene (CAAC) ligand-promoted nitro deoxygenative hydroboration with cost-effective chromium catalysis. Using 1 mol % of CAAC-Cr precatalyst, the addition of HBpin to nitro scaffolds leads to deoxygenation, allowing for the retention of various reducible functionalities and the compatibility of sensitive groups toward hydroboration, thereby providing a mild, chemoselective, and facile strategy to form anilines, as well as heteroaryl and aliphatic amine derivatives, with broad scope and particularly high turnover numbers (up to 1.8 × 106). Mechanistic studies, based on theoretical calculations, indicate that the CAAC ligand plays an important role in promoting polarity reversal of hydride of HBpin; it serves as an H-shuttle to facilitate deoxygenative hydroboration. The preparation of several commercially available pharmaceuticals by means of this strategy highlights its potential application in medicinal chemistry.
- Zhao, Lixing,Hu, Chenyang,Cong, Xuefeng,Deng, Gongda,Liu, Liu Leo,Luo, Meiming,Zeng, Xiaoming
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supporting information
p. 1618 - 1629
(2021/01/25)
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- Silver nanoparticles supported on P, Se-codoped g-C3N4 nanosheet as a novel heterogeneous catalyst for reduction of nitroaromatics to their corresponding amines
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P, Se-codoped g-C3N4 (PSeCN) nanosheet was in situ prepared by facile thermal polymerization of melamine, phosphonitrilic chloride trimer, and selenium black powder as the precursors. It was found as a suitable support for the immobilization of silver nanoparticles (Ag NPs). The prepared nanocatalyst was fully characterized via standard analysis methods including EDX, ICP-OES, XRD, FT-IR, SEM, TEM, and BET. This PSeCN/Ag nanocatalyst with a higher specific surface area compared with CN, showed excellent catalytic activity towards the reduction of several nitroaromatic compounds using sodium borohydride (NaBH4) in short reaction times with high efficiency and good selectivity in water as a green solvent. Significantly, the above-mentioned nanocomposite could be reused six times without appreciable loss of its catalytic activity.
- Elhampour, Ali,Heravi, Majid M.,Nemati, Firouzeh,Piri, Mohadese
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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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- Chemoselective Hydrogenation of Nitroarenes Using an Air-Stable Base-Metal Catalyst
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The reduction of nitroarenes to anilines as well as azobenzenes to hydrazobenzenes using a single base-metal catalyst is reported. The hydrogenation reactions are performed with an air-and moisture-stable manganese catalyst and proceed under relatively mild reaction conditions. The transformation tolerates a broad range of functional groups, affording aniline derivatives and hydrazobenzenes in high yields. Mechanistic studies suggest that the reaction proceeds via a bifunctional activation involving metal-ligand cooperative catalysis.
- Zubar, Viktoriia,Dewanji, Abhishek,Rueping, Magnus
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supporting information
p. 2742 - 2747
(2021/05/05)
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- A suitable modified palladium immobilized on imidazolium supported ionic liquid catalysed transfer hydrogenation of nitroarenes
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The first well-defined modified palladium immobilized on imidazolium supported ionic liquid catalyst has been developed for the transfer hydrogenation of nitroarenes to anilines in good to excellent yields with formic acid as reducing agent. This methodology applies eco-friendly a reducing agent which is non-toxic, water soluble, more stable and simpler to handle. Particularly, the process constitutes a rare model of base-free transfer hydrogenations. The catalyst was reused up to nine consecutive cycles without any significance loss in its activity.
- Atheeswari, Alagudurai,Kanimozhi, Nallusamy,Karthikeyan, Parasuraman,Shanmugapriya, Ramasamy
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- Mechanochemical Transformation of CF3 Group: Synthesis of Amides and Schiff Bases
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We communicate two mild, solvent-free mechanochemical coupling transformations of CF3 group with nitro compounds into amides or Schiff bases employing Ytterbia as a catalyst. This process proceeds via C?F bond activation, accompanied with utilisation of Si-based reductants/oxygen scavengers – reductants of the nitro group. The scope and limitations of the disclosed methodologies are thoroughly studied. To the best of our knowledge, this work is the first example of mechanical energy promoted transformation of the inert CF3 group into other functionalities. (Figure presented.).
- Mkrtchyan, Satenik,Jakubczyk, Micha?,Lanka, Suneel,Yar, Muhammad,Ayub, Khurshid,Shkoor, Mohanad,Pittelkow, Michael,Iaroshenko, Viktor O.
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supporting information
p. 5448 - 5460
(2021/10/19)
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- Hydroboration reduction reaction of aromatic nitro compounds without transition metal catalysis
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The invention relates to a hydroboration reduction reaction of aromatic nitro compounds without transition metal catalysis. According to the method, triethyl boron and potassium tert-butoxide are used as catalysts for the first time, and an aromatic nitro compound and pinacol borane which is low in price and easy to obtain can be conveniently catalyzed to be subjected to a hydroboration reduction reaction under mild conditions to prepare aromatic amine products. Compared with a traditional method, the method generally has the advantages that the catalyst is cheap and easy to obtain, operation is convenient, and reaction is safe. The selective hydroboration reduction reaction of the non-transition metal reagent catalyzed aromatic nitro compound and pinacol borane is realized for the first time, and a practical new reaction strategy is provided for laboratory preparation or industrial production of aromatic amine products.
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Paragraph 0006; 0021-0024
(2021/07/31)
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- COPPER NANOPARTICLE BASED CHEMOSELECTIVE REDUCTION
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The instant invention provides processes for a chemo selective reduction of a nitro group within a compound in the presence of other groups which can also be reduced. This aspect of the present invention provides an ammonia borane (AB) initiated chemoselective reduction process of a nitro group contained within a compound in the presence of a copper (Cu) nanoparticle based catalyst. The invention is also directed to Copper (Cu) nanoparticle (NP) based catalysts, selected from Cu/WOx, Cu/SiO2, and Cu/C; wherein x represents an integer having a value of from about 2 to about 3.5, used in the chemo selective reduction of a nitro group contained within a compound in the presence of other groups which can also be reduced.
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Paragraph 0050; 0051
(2021/11/20)
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- Method for preparing amine through catalytic reduction of nitro compound by cyclic (alkyl) (amino) carbene chromium complex
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The cyclic (alkyl) (amino) carbene chromium complex is prepared from corresponding ligand salt, alkali and CrCl3 and used for catalyzing pinacol borane to reduce nitro compounds in an ether solvent under mild conditions to generate corresponding amine. The method for preparing amine has the advantages of cheap and accessible raw materials, mild reaction conditions, wide substrate application range, high selectivity and the like, and is simple to operate.
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Paragraph 0015
(2021/04/17)
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- Microwave-assisted reduction of aromatic nitro compounds with novel oxo-rhenium complexes
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The reduction of several aromatic nitro compounds to amines by means of the two novel catalytic systems ([IMes]2ReOBr3)/PhSiH3 and ([Py]3ReNOBr2)/PhSiH3 under microwave irradiation is here reported. These two systems were able to perform the reduction of nitro groups with higher TON and TOF when compared with previously reported systems based on oxo-rhenium core under standard heating, although they showed a lesser broad reaction scope compared with the known systems.
- Blacque, Olivier,Grieco, Gabriele
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- Selective Carbon-Carbon Bond Amination with Redox-Active Aminating Reagents: A Direct Approach to Anilines?
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Amines are among the most fundamental motifs in chemical synthesis, and the introduction of amine building blocks via selective C—C bond cleavage allows the construction of nitrogen compounds from simple hydrocarbons through direct skeleton modification. Herein, we report a novel method for the preparation of anilines from alkylarenes via Schmidt-type rearrangement using redox-active amination reagents, which are easily prepared from hydroxylamine. Primary amines and secondary amines were prepared from corresponding alkylarenes or benzyl alcohols under mild conditions. Good compatibility and valuable applications of the transformation were also displayed.
- Qiu, Xu,Wang, Yachong,Su, Lingyu,Jin, Rui,Song, Song,Qin, Qixue,Li, Junhua,Zong, Baoning,Jiao, Ning
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p. 3011 - 3016
(2021/09/13)
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- Minimization of Back-Electron Transfer Enables the Elusive sp3 C?H Functionalization of Secondary Anilines
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Anilines are some of the most used class of substrates for application in photoinduced electron transfer. N,N-Dialkyl-derivatives enable radical generation α to the N-atom by oxidation followed by deprotonation. This approach is however elusive to monosubstituted anilines owing to fast back-electron transfer (BET). Here we demonstrate that BET can be minimised by using photoredox catalysis in the presence of an exogenous alkylamine. This approach synergistically aids aniline SET oxidation and then accelerates the following deprotonation. In this way, the generation of α-anilinoalkyl radicals is now possible and these species can be used in a general sense to achieve divergent sp3 C?H functionalization.
- Zhao, Huaibo,Leonori, Daniele
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supporting information
p. 7669 - 7674
(2021/03/08)
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- Method for synthesizing heteroatom- substituted aromatic compound from styrene compound
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The invention discloses a method for synthesizing a heteroatom-substituted aromatic compound from a styrene compound, which comprises the following steps of: mixing a styrene compound with a general formula (I) and a heteroatom-containing compound with a general formula (II), and reacting in the presence of an acid additive and an organic solvent to obtain a heteroatom-substituted compound with ageneral formula (III). According to the synthesis method disclosed by the invention, a large amount of styrene compounds are used as raw materials and react to generate aromatic amine or phenol compounds under the action of no metal catalysis; and compared with the traditional aromatic amine and phenol synthesis method, the method has the advantages of high yield, simple conditions, low waste discharge amount, no metal participation, simple reaction equipment, easiness in industrial production and the like.
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Paragraph 0173-0176
(2021/02/06)
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- Heterogeneous photocatalysis of azides: Extending nitrene photochemistry to longer wavelengths
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The photodecomposition of azides to generate nitrenes usually requires wavelengths in the 300 nm region. In this study, we show that this reaction can be readily performed in the UVA region (368 nm) when catalyzed by Pd-decorated TiO2. In aqueous medium the reaction leads to amines, with water acting as the H source; however, in non-protic and non-nucleophilic media, such as acetonitrile, nitrenes recombine to yield azo compounds, while azirine-mediated trapping occurs in the presence of nucleophiles. The heterogeneous process facilitates catalyst separation while showing great chemoselectivity and high yields.
- Argüello, Juan E.,Lanterna, Anabel E.,Lemir, Ignacio D.,Scaiano, Juan C.
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supporting information
p. 10239 - 10242
(2020/10/02)
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- P-iodoaniline and preparation method thereof
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The invention provides p-iodoaniline and a preparation method thereof, and belongs to the technical field of organic synthesis. A purpose of the invention is to solve the problems of excessive elemental iodine consumption and increased three wastes caused by a large amount of sulfate generated by reaction in the existing p-iodoaniline preparation method. The method comprises: 1, adding aniline andwater into a first reaction container according to a certain ratio, adding elemental iodine into the first reaction container in a dropwise manner, stirring to prepare a first solution, cooling the first solution to 0-20 DEG C, adding hydrogen peroxide with a mass concentration of 30% in a dropwise manner, and carrying out sampling analyzing until the mass percentage content of aniline is less than 0.5% to obtain a second solution; 2, adding sodium sulfite into the second solution, stirring for 0.4-0.5 h to obtain a third solution, and carrying out suction filtration on the third solution toobtain a brown crystal; and 3, pouring the brown crystal into a second reaction container, and carrying out extraction purification treatment to obtain the p-iodoaniline finished product. According tothe invention, with the method, the consumption of elemental iodine is low, the crude product content is high, and the generation of sulfate is avoided.
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Paragraph 00349-0053
(2020/02/14)
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- A novel DMSO-assisted regioselective iodination of aniline analogues
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A metal- and oxidant-free electrophilic iodination of aniline analogues was achieved in high to excellent yields at room temperature in MTBE with 0 or 3.5 equivalents of DMSO. Examined substituents include N-alkyl, N,N-dialkyl, N-morpholinyl and N-piperazinyl as well as methyl, Br, CN and CO2CH3 aryl ring substitutions.
- Bovonsombat, Pakorn,Lorpaiboon, Wanutcha,Laoboonchai, Sarocha,Sriprachaya-anunt, Prima,Yimkosol, Warangkana,Siriphatcharachaikul, Natthapatch,Siricharoensang, Pornpawit,Kangwannarakul, Terawee,Maeda, Jin,Losuwanakul, Satreerat,Mahesh Abhyankar, Maitraye
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- Atomically Dispersed Co Catalyst for Efficient Hydrodeoxygenation of Lignin-Derived Species and Hydrogenation of Nitroaromatics
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Single-atom catalysts (SACs) have attracted much attention due to their outstanding catalytic performance in heterogeneous catalysis. Here, we report a template sacrificial method to fabricate an atomically dispersed Co catalyst; three kinds of silica templates with different microstructures (MCM-41, SBA-15, and FDU-12) were employed and the effect of pore structure of the templates on the dispersity of Co was investigated. The catalysts fabricated with different templates presented different Co dispersities, leading to distinguishing catalytic performance. The optimized Co1?NC-(SBA) catalyst with atomically dispersed Co displayed outstanding catalytic activity for the hydrodeoxygenation (HDO) of lignin-derived species as well as the hydrogenation of various nitroaromatics. The reaction mechanism of the HDO of vanillin was investigated by using density functional theory calculations as well.
- Du, Congcong,Gao, Shutao,Gao, Yongjun,Huang, Jianyu,Meng, Tao,Qiao, Yuqing,Shang, Ningzhao,Shen, Tongde,Wang, Chun,Wang, Haijun,Wang, Junmin,Wang, Zhi,Wu, Qiuhua,Zhang, Longkang
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p. 8672 - 8682
(2020/09/18)
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- Synthesis, characterization, and catalytic activity of half-sandwich ruthenium complexes with pyridine/phenylene bridged NHC = E (NHC = N-heterocyclic carbene, E = S, Se) ligands
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Three half-sandwichruthenium(II) complexes with pyridine/phenylene bridged NHC = E (NHC = N-heterocyclic carbene, E = S, Se) ligands [Ru(p-cymene)L](PF6)1–2 (1a–1c, L = ligand) were synthesized and characterized. All ruthenium complexes were fully characterized by 1H and 13C NMR spectra, mass spectrometry, and single-crystalX-ray diffraction methods. Moreover, the half-sandwich ruthenium complexes with NHC = E ligands showed highly catalytic activities towards to the tandem dehydrogenation of ammonia borane (AB) and hydrogenation of R–NO2 to R–NH2 at 353 K in water.
- Jia, Wei-Guo,Du, Teng-Teng,Gao, Li-Li,Du, Jun
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- Half-sandwich ruthenium complexes with Schiff base ligands bearing a hydroxyl group: Preparation, characterization and catalytic activities
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Three half-sandwich ruthenium(II) complexes with hydroxyl group functionalized Schiff-base ligands [Ru(p-cymene)LCl] (2a-2c) have been synthesized and characterized. All ruthenium complexes were fully characterized by 1H and 13C NMR spectra, mass spectrometry and infrared spectrometry. The molecular structure of ruthenium complex 2c was confirmed by single-crystal X-ray diffraction methods. Furthermore, these half-sandwich ruthenium complexes were found to exhibit high catalytic activity for nitro compounds reduction using NaBH4 reducing agent in the presence of cetyltrimethylammonium bromide (CTAB) in water at room temperature.
- Jia, Wei-Guo,Wang, Zhi-Bao,Zhi, Xue-Ting
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- Tuning acylthiourea ligands in Ru(II) catalysts for altering the reactivity and chemoselectivity of transfer hydrogenation reactions, and synthesis of 3-isopropoxy-1H-indole through a new synthetic approach
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Ru(II)-p-cymene complexes (1–3) containing picolyl based pseudo-acylthiourea ligands (L1-L3) were synthesized and characterized. The crystallographic study confirmed the molecular structures of all the ligands (L1-L3) and complex 3. The catalytic activity of the complexes was tested mainly towards TH of carbonyl compounds and nitroarenes. The influence of steric and electronic effects of the ligands on the chemoselectivity and reactivity were reported. The catalytic activity was enhanced and chemoselectivity was switched after tuning the ligands in the catalysts, compared to their corresponding unmodified Ru(II)-p-cymene complexes. The catalysis was extended to a broad range of substrates including some challenging systems like furfural, benzoylpyridine, benzoquinone, chromanone, etc. The strategy of tuning the bifunctional ligands in the catalysts for effective and selective catalysis worked nicely. Further, the catalysis was extended to one pot synthesis of 3-isopropoxyindole from 2-nitrocinnamaldehyde, the first synthetic route similar to Baeyer Emmerling indole synthesis. All the catalytic experiments exhibited high conversion and selectivity.
- Sathishkumar, Pushpanathan N.,Prabha, Padinhattath Sachind,Bhuvanesh, Nattamai S.P.,Karvembu, Ramasamy
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- Cobalt oxide NPs immobilized on environmentally benign biological macromolecule-derived N-doped mesoporous carbon as an efficient catalyst for hydrogenation of nitroarenes
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Highly nitrogen-doped mesoporous carbon (N-mC) material incorporated cobalt oxide nanoparticles was synthesized through simple pyrolysis of environmentally friendly chitosan-polyaniline-Co(OAc)2 precursor in one-step. The as-prepared catalyst named CoO&at;N-mC with 14.65 ?wtpercent nitrogen content was characterized by different analysis techniques. The heterogeneous catalyst exhibits outstanding catalytic activity for the reduction of a variety of nitroaromatic compounds in the presence of NaBH4 as a reducing agent in water as a green solvent at 75 ?°C. Utilization of natural biological macromolecules such as chitosan as green and cheap starting material with harmless aniline and earth-abundant cobalt salt, facile synthesis, excellent product yield, short reaction time, high chemoselectivity, sustainable and mild reaction condition, and reusability of catalyst for at least five cycles without any significant decline in the catalytic efficiency are some prominent merits of this new nanocatalyst.
- Elhampour, Ali,Nanadegani, Zahra Soleimani,Nemati, Firouzeh,Rangraz, Yalda
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- Palladium supported on metal–organic framework as a catalyst for the hydrogenation of nitroarenes under mild conditions
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Sustainable development demands an environmentally friendly and efficient method for the hydrogenation of organic molecules, including the hydrogenation of functionalized nitroarenes. In this study, a highly active and selective metal–organic framework-supported palladium catalyst was prepared for the catalytic hydrogenation of nitroarenes. High selectivity (>99%) and excellent yield (98%) of aniline were realized after 2 hours in ethanol under hydrogen (1 atm) at room temperature. The reductions were successfully carried out in the presence of a wide range of other reducible functional groups. More importantly, the catalyst was very stable without the loss of its catalytic activity after five cycles.
- Bao, Lingxiang,Fei, Teng,Li, Jiazhe,Pang, Siping,Sun, Chenghui,Yan, Zhiyuan,Yu, Zongbao
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- CO-free, aqueous mediated, instant and selective reduction of nitrobenzeneviarobustly stable chalcogen stabilised iron carbonyl clusters (Fe3E2(CO)9, E = S, Se, Te)
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Highly stable and thermally robust iron chalcogenide carbonyl clusters Fe3E2(CO)9(E = S, Se or Te) have been explored for the reduction of nitrobenzene. A 15 min thermal heating of an aqueous solution of nitrobenzene and hydrazine hydrate in the catalytic presence of Fe3E2(CO)9(E = S, Se or Te) clusters yield average to excellent aniline transformations. Among the S, Se and Te based iron chalcogenised carbonyl clusters, the diselenide cluster was found to be most efficient and produce almost 90% yield of the desired amino product, the disulfide cluster was also found to be significantly active, produce the 85% yield of amino product, while the ditelluride cluster was not found to be active and produced only 49% yield of the desired product. The catalyst can be reused up to three catalytic cycles and it needs to be dried in an oven for one hour prior to reuse for the best results. The developed method is inexpensive, environmentally benign, does not require any precious metal or a high pressure of toxic CO gas and exclusively brings the selective reduction of the nitro group under feasible and inert free conditions.
- Joshi, Raj Kumar,Kumari, Sangeeta,Sharma, Charu,Soni, Aditi,Srivastava, Avinash Kumar
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p. 32516 - 32521
(2020/09/17)
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- Ultrasound-assisted rapid reduction of nitroaromatics to anilines using gallium metal
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The reduction of nitroaromatic compounds to anilines is widely used throughout organic synthesis. Typical methods of performing this transformation utilize hydrogenation over a pyrophoric catalyst or a finely divided reducing metal, which often affords heterogeneous mixtures that are difficult to purify. Herein, we report for the first time the use of gallium metal as a reducing agent in organic synthesis. The reaction proceeds under aerobic conditions and affords homogeneous mixtures for a convenient workup. Using this method, twelve anilines were obtained in 33% to quantitative yields with short reaction times of 10-60 minutes.
- Bento, Ian,Bernaldez, Mabel,Noguchi, Ryden,Kawakami, Joel
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supporting information
p. 1404 - 1407
(2020/03/31)
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- Commercially Available CuO Catalyzed Hydrogenation of Nitroarenes Using Ammonia Borane as a Hydrogen Source
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Tandem ammonia borane dehydrogenation and nitroarenes hydrogenation has been reported as a novel strategy for the preparation of aromatic amines. However, the practical application of this strategy is subjected to the high-cost and tedious preparation of supported noble metal nanocatalysts. The commercially available CuO powder is herein demonstrated to be a robust catalyst for hydrogenation of nitroarenes using ammonia borane as a hydrogen source under mild conditions. Numerous amines (even sterically hindered, halogenated, and diamines) could be obtained through this method. This monometallic catalyst is characteristic of support-free, excellent chemoselectivity, low-cost, and high recyclability, which will favor its future utilization in preparative reduction chemistry. Mechanistic studies are also carried out to clarify that diazene and azoxybenzene are key intermediates of this heterogeneous reduction.
- Du, Jialei,Chen, Jie,Xia, Hehuan,Zhao, Yiwei,Wang, Fang,Liu, Hong,Zhou, Weijia,Wang, Bin
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p. 2426 - 2430
(2020/03/30)
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- Mild deprotection of the: N-tert -butyloxycarbonyl (N -Boc) group using oxalyl chloride
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We report a mild method for the selective deprotection of the N-Boc group from a structurally diverse set of compounds, encompassing aliphatic, aromatic, and heterocyclic substrates by using oxalyl chloride in methanol. The reactions take place under room temperature conditions for 1-4 h with yields up to 90percent. This mild procedure was applied to a hybrid, medicinally active compound FC1, which is a novel dual inhibitor of IDO1 and DNA Pol gamma. A broader mechanism involving the electrophilic character of oxalyl chloride is postulated for this deprotection strategy. This journal is
- Awuah, Samuel G.,George, Nathaniel,Ofori, Samuel,Parkin, Sean
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p. 24017 - 24026
(2020/07/23)
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- Eco-friendly hydrogenation of aryl azides to primary amines on graphene oxide-decorated bimetallic Rh-Pt nanoparticles (RhPt@GO NPs)
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Graphene oxide-supported rhodium/platinum (Rh-Pt) nanoparticles (Rh-Pt@GO NPs) are a promising catalyst for the reduction of aryl azides to primary amines. Rh-Pt@GO NPs have been produced by the microwave-assisted sonochemical method. This catalyst showed superior catalytic activity to afford quantitative yields of primary amines under an extremely mild condition in the presence of sodium borohydride. The synthesized novel catalyst was easily recovered by centrifugation and reused without loss of its catalytic activity. The spectroscopic analyses of the RhPt@GO NPs indicated the formation of highly crystalline, monodisperse, and colloidally stable RhPt@GO NPs.
- Kilbas, Benan,Kara, Belguzar Yasemin
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- Sodium sulfate-hydrogen peroxide-sodium chloride adduct: selective protocol for the oxidative bromination, iodination and temperature dependent oxidation of sulfides to sulfoxides and sulfones
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The regioselective bromination and iodination of unprotected aromatic primary amines using enclathrated hydrogen peroxide as an oxidant under mild conditions has been developed, in which potassium bromide (KBr) and potassium iodide (KI) were used as brominating and iodinating agents, respectively. The adduct shows not only regioselectivity for para- or ortho-isomers but also a remarkable chemoselectivity for monobromination. Selective oxidation of sulfides to sulfoxides and sulfones has also been studied and good to excellent yields of the desired products were obtained. Acetic acid was found to be the solvent of choice for these reactions. This simple method represents an ecologically benign and alternative pathway for the oxidative halogenation of anilines and the oxidation of sulfides to sulfoxides and sulfones.
- Gayakwad, Eknath M.,Patel, Khushbu P.,Shankarling, Ganapati S.
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supporting information
p. 6001 - 6009
(2019/04/17)
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- Sustainable visible light assisted in situ hydrogenation via a magnesium-water system catalyzed by a Pd-g-C3N4 photocatalyst
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A non-hazardous and relatively mild protocol was formulated for an effectual hydrogen generation process via a "magnesium-activated water" system with a Pd-g-C3N4 photocatalyst under visible light at room temperature. Water functions photochemically as a hydrogen donor without any external source with the Pd-g-C3N4 photocatalyst. The synthesized Pd-g-C3N4 photocatalyst is highly efficient under visible light for the selective reduction of a wide range of unsaturated derivatives and nitro compounds to afford excellent yields (>99%). The photocatalyst Pd-g-C3N4 could be easily recovered and reused for several runs without any deactivation during the photochemical hydrogen transfer reaction process.
- Sharma, Priti,Sasson, Yoel
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supporting information
p. 261 - 268
(2019/01/28)
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- Hydrogenation of Functionalized Nitroarenes Catalyzed by Single-Phase Pyrite FeS2 Nanoparticles on N,S-Codoped Porous Carbon
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Catalytic hydrogenation of nitroarenes is an industrially very important and environmentally friendly process for the production of anilines; however, highly chemoselective reduction of nitroarenes decorated with one or more reducible groups in a nitroarene molecule remains a challenge. Herein, a novel hybrid non-noble iron-based nanocatalyst (named as FeS2/NSC) was developed, which was prepared from biomass as C and N source together with inexpensive Fe(NO3)3 as Fe source through high-temperature pyrolysis in a straightforward and cost-effective procedure. Comprehensive characterization revealed that single-phase pyrite FeS2 nanoparticles with precisely defined composition and uniform size were homogeneously dispersed on N,S-codoped porous carbon with large specific surface area, hierarchical porous channels, and high pore volume. The resultant catalyst FeS2/NSC demonstrated good catalytic activity for hydrogenation of functionalized nitroarenes with good tolerance of various functional groups in water as a sustainable and green solvent. Compared with bulk pyrite FeS2 and other non-noble metal-based heterogeneous catalysts reported in the literature, a remarkably enhanced activity was observed under mild reaction conditions. More importantly, FeS2/NSC displayed exclusive chemoselectivity for the reduction of nitro groups for nitroarenes bearing varying readily reducible groups.
- Duan, Yanan,Dong, Xiaosu,Song, Tao,Wang, Zhaozhan,Xiao, Jianliang,Yuan, Youzhu,Yang, Yong
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- Diruthenium complex catalyzed reduction of nitroarenes-investigation of reaction pathway
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A diruthenium complex, [(L)Ru2(η6-C6H6)2Cl2](PF6)2 (1) (L = 5-phenyl-2,8-di-2-pyridinylanthyridine), was prepared and characterized. This diruthenium complex 1 was found to be an efficient catalyst for the reduction of aromatic nitro compounds leading to the corresponding aniline derivatives with the use of hydrazine as the reducing agent at 80 °C in an ethanol solution. Catalytic activity of 1 towards various possible intermediates leading to anilines was investigated to understand the reaction pathway. These studies indicate that this reduction proceeds via a direct route as evidenced by hydroxylamines being observed as the major intermediate followed by the appearance of aniline under the catalytic conditions. Thus, the reaction pathway of this catalytic system is discussed.
- Lin, Shih-Chieh Aaron,Liu, Yi-Hung,Peng, Shie-Ming,Liu, Shiuh-Tzung
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- Green and convenient protocols for the efficient reduction of nitriles and nitro compounds to corresponding amines with NaBH4 in water catalyzed by magnetically retrievable CuFe2O4 nanoparticles
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Abstract: In this study, firstly, CuFe2O4 nanoparticles were prepared by a simple operation. The structure of the mentioned nanoparticles was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, inductively coupled plasma-optical emission spectrometry, vibrating sample magnetometer and also Brunauer–Emmett–Teller and Barrett–Joyner–Halenda analyses. The prepared magnetically copper ferrite nanocomposite was successfully applied as a simple, cost-effective, practicable, and recoverable catalyst on the green, highly efficient, fast, base-free, and ligand-free reduction of nitriles and also on the affordable and eco-friendly reduction of nitro compounds with the broad substrate scope to the corresponding amines with NaBH4 in water at reflux in high to excellent yields. Graphical abstract: [Figure not available: see fulltext.].
- Zeynizadeh, Behzad,Mohammad Aminzadeh, Farkhondeh,Mousavi, Hossein
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- Starch functionalized creatine for stabilization of gold nanoparticles: Efficient heterogeneous catalyst for the reduction of nitroarenes
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Selective reduction of nitroaromatic pollutants into amines with recoverable and reusable heterogeneous catalysts is highly desirable. Herein, we prepared and characterized an efficient novel catalyst comprising 4 nm size Au nanoparticles supported on creatine modified starch. Using this catalyst, efficient reduction of nitroarenes into amines at room temperature in aqueous media was achieved. The presence of creatine in the structure of the catalyst plays important role in amount of Au loading, efficiency of the catalyst, recycling times, and leaching of Au compared to starch supported Au without creatine.
- Gholinejad, Mohammad,Dasvarz, Neda,Shojafar, Mohammad,Sansano, José M.
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- Catalytic hydrogenation of carbonyl and nitro compounds using an [: N, O] -chelate half-sandwich ruthenium catalyst
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A series of N,O-chelate half-sandwich ruthenium complexes for both carbonyl and nitro compound hydrogenation have been synthesized based on β-ketoamino ligands. All complexes exhibited high activity for the catalytic hydrogenation of a series of ketones and nitroarenes with molecular H2 as the reducing reagent in aqueous medium. Consequently, the catalytic system showed the catalytic TON values of 950 for 1-phenylethanol in acetophenone hydrogenation and 1960 for 1-chloro-4-nitrobenzene in p-chloroaniline hydrogenation. Good catalytic activity was displayed for various kinds of substrates with either electron-donating or electron-withdrawing groups. The neutral ruthenium complexes 1-4 were fully characterized using NMR, IR, and elemental analysis. Molecular structures of complexes 2 and 4 were further confirmed using single-crystal X-ray diffraction analysis.
- Yao, Zi-Jian,Zhu, Jing-Wei,Lin, Nan,Qiao, Xin-Chao,Deng, Wei
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p. 7158 - 7166
(2019/06/13)
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- Sustainable Protocol for the Reduction of Nitroarenes by Heterogeneous Au@SBA-15 with NaBH4 under Flow Conditions
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A gold-incorporated SBA-15 catalyst was prepared by a solvent-free ball-milling approach. The catalyst showed high reactivity and selectivity in the reduction of a variety of nitroarenes to anilines operating in absolute EtOH with NaBH4 as reducing agent. The catalyst was reused in batch conditions over five consecutive runs without any losses of activity or selectivity. Considering the high chemical stability and reusability of the catalytic system, a continuous-flow protocol was also investigated and defined to minimize the generation of waste and optimize the continuous reuse of the catalyst. Benefits of flow conditions were proven by turnover numbers that increased from 47.5 to 1902 and also by the minimization of both leaching (9.5 vs. 1 ppm) and E-factor values (8 vs. 23 in batch).
- Ferlin, Francesco,Giannoni, Tommaso,Zuliani, Alessio,Piermatti, Oriana,Luque, Rafael,Vaccaro, Luigi
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p. 3178 - 3184
(2019/02/19)
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- A ruthenium bisoxazoline complex as a photoredox catalyst for nitro compound reduction under visible light
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An unreported ruthenium(ii) complex containing bisoxazoline ligands has been synthesized and characterized. To test the catalytic ability of the ruthenium complex, the synthesis of anilines from nitro compounds in the presence of a mild reducing agent sodium borohydride and visible light has been developed. Mechanistic studies involving the experiment and DFT calculations suggest that the reaction could involve a radical pathway with the assistance of a photoredox catalyst.
- Jia, Wei-Guo,Cheng, Ming-Xia,Gao, Li-Li,Tan, Siu Min,Wang, Chao,Liu, Xiaogang,Lee, Richmond
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supporting information
p. 9949 - 9953
(2019/07/15)
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- Selective Reduction of Nitroarenes Catalyzed by Sustainable and Reusable DNA-supported Nickel Nanoparticles in Water at Room Temperature
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Abstract: In this research, a novel, biodegradable and environmentally friendly catalyst composed of nickel nanoparticles supported on DNA was prepared and fully characterized by Fourier transform infrared spectroscopy, high resolution transmission electron microscopy, energy-dispersive X-ray analysis, X-ray photoelectron spectroscopy, UV–vis spectroscopy, inductively coupled plasma optical emission spectroscopy, and elemental analysis. The catalyst exhibited remarkable catalytic activity and chemoselectivity for the reduction of various substituted nitroarenes with sodium borohydride (NaBH4) as the source of inexpensive hydride in water at room temperature. High turnover frequency and selectivity were observed for the reduction of all tested substrates. Interestingly, the catalyst could be recovered conveniently for multiple recycling reactions with sustained activity. Furthermore, nearly no nickel species was leached out from the catalyst during the course of reaction, proving the true heterogeneity in the present catalytic protocol. Graphical Abstract: The reduction of various nitroaromatic compounds into their corresponding amines is achieved by DNA supported nickel nanoparticles with the sodium borohydride as the reducing agent in water at room temperature. [Figure not available: see fulltext.].
- Niakan, Mahsa,Asadi, Zahra
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- Novel protocol for synthesis of 1,4-diiminocurcumin stabilized silver nanoparticles and application as heterogenous recyclable catalyst and antibacterial agent
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Abstract: Curcumin [(1E, 6E)-1,7-bis(4-hydroxy-3-methoxy-phenyl)-1,6-heptadiene-3,5-dione] is a low molecular weight yellow-orange polyphenolic pigment extracted from the powdered rhizome of Curcuma longa. Curcumin has wide medicinal applications as an antioxidant, anti-inflammatory, cancer chemopreventive, and potentially chemotherapeutic agents as well as stabilizer/reducing agent in silver nanoparticles (AgNPs) synthesis. However, the low solubility of curcumin in aqueous solutions limits its applications and also, many of AgNP synthetic processes lack a greener synthetic route. In the present work, a Schiff base of curcumin is synthesized condensing curcumin and 1,4-diaminobutane in 2:1 ratio. The resulting product shows improvement in solubility in water and favours the synthesis of AgNPs in aqueous medium at room temperature, acting as a self-reducing/stabilizing agent. This proposed synthetic route is simple, feasible and green. The size and morphology of AgNPs are analyzed by TEM, SEM, EDS and XRD techniques. The recyclable AgNPs as a heterogeneous catalyst in the reduction of nitroaromatics to amino compounds is environmentally benign and can be re-used up to 5th cycle without considerable loss of its catalytic activity. Moreover, both Cur-1,4 and AgNPs show bactericidal properties against bacterial strains (Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa) which find medicinal importance in future. Graphic abstract: A greener approach has been proposed for the preparation of AgNPs stabilized on curcumin based Schiff base. The AgNPs finds applications as efficient, easily recyclable heterogenous catalyst in the reduction of nitroaromatics to environmentally benign aminoaromatics as well as an antibacterial agent.[Figure not available: see fulltext.].
- Gogoi, Nishi Gandha,Handique, Jyotirekha G
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- Ultra-low-loading palladium nanoparticles stabilized on nanocrystalline Polyaniline (Pd@PANI): A efficient, green, and recyclable catalyst for the reduction of nitroarenes
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Ultra-low-loading Pd@PANI nanocomposites (0.048 w.t% Pd) were synthesized via a method that combined interfacial polymerization and in situ composite with camphor sulfonic acid ((+)-CSA) as a dopant. Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectra, and X-ray photoelectron spectroscopy (XPS) were performed to characterize the structures. It can be used as an efficient catalyst for the reduction of nitroarenes in aqueous solution by using a smaller amount of NaBH4 (2.5 equiv.) at room temperature with high activity (TON?=?3.4?×?103), good stability (cycled eight times), as well as wide applicability (27 substrates). The catalyst also showed a marvelous activity in the gram-level reaction (yield?=?92%). UV–Visible spectrophotometry was used to investigate the reaction kinetics for the reduction of 4-nitrophenol to 4-aminophenol, and the results reconfirmed the excellent performance of the catalyst. The unique properties and superior performance of the prepared ultra-low-loading Pd@PANI nanocomposites lead it be an attractive alternative catalyst for conventional organic catalytic applications.
- Wang, Gang,Yuan, Shuo,Wu, Zhiqiang,Liu, Wanyi,Zhan, Haijuan,Liang, Yanping,Chen, Xiaoyan,Ma, Baojun,Bi, Shuxian
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