- Magnetic nanoparticle-tethered Schiff base–palladium(II): Highly active and reusable heterogeneous catalyst for Suzuki–Miyaura cross-coupling and reduction of nitroarenes in aqueous medium at room temperature
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As a continuation of our efforts to develop new heterogeneous nanomagnetic catalysts for greener reactions, we identified a Schiff base–palladium(II) complex anchored on magnetic nanoparticles (SB-Pd@MNPs) as a highly active nanomagnetic catalyst for Suzuki–Miyaura cross-coupling reactions between phenylboronic acid and aryl halides and for the reduction of nitroarenes using sodium borohydride in an aqueous medium at room temperature. The SB-Pd@MNPs nanomagnetic catalyst shows notable advantages such as simplicity of operation, excellent yields, short reaction times, heterogeneous nature, easy magnetic work up and recyclability. Characterization of the synthesized SB-Pd@MNPs nanomagnetic catalyst was performed with various physicochemical methods such as attenuated total reflectance infrared spectroscopy, UV–visible spectroscopy, inductively coupled plasma atomic emission spectroscopy, energy-dispersive X-ray spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, powder X-ray powder diffraction, thermogravimetric analysis and Brunauer–Emmett–Teller surface area analysis.
- Manjunatha,Koley, Tuhin S.,Kandathil, Vishal,Dateer, Ramesh B.,Balakrishna, Geetha,Sasidhar,Patil, Shivaputra A.,Patil, Siddappa A.
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- The novel reduction systems: NaBH4-SbCl3 or NaBH4-BiCl3 for conversion of nitroarenes to primary amines
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Nitroarenes can be conveniently reduced to primary amines in good to excellent yields by sodium borohydride in the presence of bismuth chloride or antimony chloride.
- Ren,Pan,Dong,Wu
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- Fe3O4@graphene oxide composite: A magnetically separable and efficient catalyst for the reduction of nitroarenes
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We reported a facile co-precipitation method to prepare a highly active Fe3O4@graphene oxide (Fe3O4@GO) composite catalyst, which was fully characterized by means of X-ray diffraction (XRD), Fourier transformed infrared (FTIR) spectroscopy, transmission electron microscopy (TEM) and N2 adsorption-desorption measurements. The results demonstrated that the Fe3O4 nanoparticles (Fe 3O4 NPs) with a small diameter of around 12 nm were densely and evenly deposited on the graphene oxide (GO) sheets. The as-prepared Fe3O4@GO composite was explored as a catalyst to reduce a series of nitroarenes for the first time, which exhibited a great activity with a turnover frequency (TOF) of 3.63 min-1, forty five times that of the commercial Fe3O4 NPs. The dosages of catalyst and hydrazine hydrate are both less than those reported. Furthermore, the composite catalyst can be easily recovered due to its magnetic separability and high stability.
- He, Guangyu,Liu, Weifeng,Sun, Xiaoqiang,Chen, Qun,Wang, Xin,Chen, Haiqun
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- NiO-Al2O3 prepared from a Ni-Al hydrotalcite precursor as an efficient catalyst for transfer hydrogenation reactions
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NiO-Al2O3 catalyst prepared by calcining a Ni-Al hydrotalcite precursor efficiently reduces nitroarenes and carbonyl compounds in presence of propan-2-ol and KOH. Presence of two different reducible groups in the substrate leads to chemoselective reduction.
- Jyothi,Raja,Talawar,Sreekumar,Sugunan,Rao
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- Efficient reduction of nitro compounds and domino preparation of 1-substituted-1H-1,2,3,4-tetrazoles by Pd(ii)-polysalophen coated magnetite NPs as a robust versatile nanocomposite
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A new, versatile, and green methodology has been developed for the efficient NaBH4-reduction of nitroarenes as well as the domino/reduction MCR preparation of 1-substituted-1H-1,2,3,4-tetrazoles using Pd(ii)-polysalophen coated magnetite NPs as an efficient heterogeneous magnetically recyclable nanocatalyst. Polysalophen was firstly prepared based on a triazine framework with a high degree of polymerization, then coordinated to Pd ions and, finally, the resulting hybrid was immobilized on magnetite NPs. The catalyst was characterized by various instrumental and analytical methods, including GPC, DLS, N2adsorption-desorption, TGA, VSM, TEM, HRTEM, EDX, XPS, XRD, and ICP analyses. The catalyst possesses dual-functionality including the reduction of nitroarenes and the construction of tetrazole rings all in one stepviaa domino protocol. High to excellent yields were obtained for both nitro reduction and the direct preparation of 1-substituted-1H-1,2,3,4-tetrazoles from nitro compounds. Insight into the mechanism was conducted by XPSin situas well as DLSin situalong with several control experiments. Recyclability of the catalyst was studied for 6 consecutive runs along with metal leaching measurements in each cycle.
- Xu, DaPeng,Xiong, Meilu,Kazemnejadi, Milad
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- REDUCTION OF AROMATIC NITRO COMPOUNDS TO AMINES BY BENZENETELLUROL
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Benzenetellurol was conveniently generated by methanolysis of phenyl trimethylsilyl telluride or reduction of diphenyl ditelluride with phosphinic acid or sodium borohydride, and smoothly reduced aromatic nitro compounds to the corresponding amines.
- Ohira, Noriyuki,Aso, Yoshio,Otsubo, Tetsuo,Ogura, Fumio
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- Synthesis of In2S3-CNT nanocomposites for selective reduction under visible light
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In2S3-carbon nanotube (In2S 3-CNT) nanocomposites have been prepared via a facile refluxing wet chemistry process. The as-synthesized In2S3-CNT nanocomposites can be used as selective and a
- Yang, Min-Quan,Weng, Bo,Xu, Yi-Jun
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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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- Synthesis, characterization, and application of easily accessible resin-encapsulated nickel nanocatalyst for efficient reduction of functionalized nitroarenes under mild conditions
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Abstract: A novel resin-encapsulated nickel nanocatalyst has been synthesized by a modified impregnation method using nickel acetate tetrahydrate in presence of sodium borohydride as a mild reducing agent. The synthesized nanocatalyst was characterized by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The concentration of nickel nanoparticles encapsulated on resin was determined by inductively coupled plasma-mass spectroscopy (ICP-MS). Further, synthesized resin-encapsulated nickel nanocatalyst was found to be stable and efficient in micromolar concentrations, for the selective reduction of functionalized nitroarenes to corresponding amines in good to high yield, under mild reaction conditions. The nanocatalyst shows excellent reusability. Graphical Abstract: SYNOPSIS A novel resin-encapsulated nickel nanocatalyst (Ni@XAD-4) was synthesized using a modified impregnation method. The nanocatalyst exhibited excellent catalytic activity towards the selective reduction of functionalized nitroarenes in the presence of NaBH 4 with reusability up to five cycles.[Figure not available: see fulltext.].
- Rani, Poonam,Singh, Kamal Nain,Kaur, Amarjit
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- Rapid and inexpensive method for reduction of nitroarenes to anilines
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Nitroarenes are reduced to corresponding anilines in good yields using ferric chloride - Zinc - Dimethyl formamide - water system.
- Desai,Swami,Hapase
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- A convenient and mild synthetic route to aminoarenes by reduction of nitroarenes with activated nickel and hydrazine hydrate
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Aminoarenes were obtained in excellent yields by reduction of corresponding nitroarenes with activated nickel powder and hydrazine hydrate. The nickel catalyst was prepared by the reduction of anhydrous nickelous chloride with Ultrasonically Dispersed Potassium.
- Li, Hongbin,Zhang, Rong,Wang, Hui,Pan, Yi,Shi, Yaozeng
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- Catalytic transfer hydrogenation of nitro arenes, aldehydes, and ketones with propan-2-ol and KOH/NaOH over mixed metal oxides
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Mixed metal oxides such as ZrO2-NiO, ZrO2-CoO, and ZrO2-Fe2O3 effectively reduce nitro arenes, aldehydes and ketones with propan-2-ol and KOH/NaOH in liquid phase reaction. The catalysts also have considerable level of reusability.
- Sonavane, Sachin U.,Jayaram, Radha V.
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- Catalytic application of 1,3,5-triazine-pentaethylenehexamine polymer-supported palladium nanoparticles in the convenient reduction of nitroarenes with sodium borohydride or hydrazine
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The catalytic activity of 1,3,5-triazine-pentaethylenehexamine (TAPEHA) polymer-supported Pd nanoparticles was investigated in the reduction of nitro arenes to the corresponding amines by NaBH4 or N2H4 .H2 O. Optimized reaction conditions for both systems were successfully tested on 20 nitroarenes with different characteristics. Considerably high yields (80%-98% in NaBH4 and 85%-98% in N2H4) were obtained in a short time and at ambient temperature. In addition to these methods being selective against other reducible functionalities such as -CN, -Br, -Cl, and -I, the catalyst can be recovered easily and reused more than ten times.
- Gen?, Hayriye,Zengin, Mustafa,Kü?ükislamo?lu, Mustafa,Imamoglu, Mustafa,Toplan, Hüseyin ?zkan,Arslan, Mustafa
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- Efficient reductions of various nitroarenes with scrap automobile catalyst and NaBH4
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The effect of scrap automobile catalyst (SAC), a waste material, was investigated as a catalyst for the reduction of nitroarenes to the corresponding amines with sodium borohydride in aqueous ethanol at 5-25 °C. Along with the observed high conversions, the SAC and NaBH4 combination also exhibits a selectively catalyzed reduction in compounds containing other reducible functionalities, such as CN, Br, Cl and I. Recycling automobile wastes into a catalyst for organic reactions will offer both environmental protection and economic advantages. As a result, an effective, easy to use, low-priced and reliable method has been developed.
- Genc, Hayriye
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- A new magnetically recyclable heterogeneous palladium(II) as a green catalyst for Suzuki-Miyaura cross-coupling and reduction of nitroarenes in aqueous medium at room temperature
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In the current work, a new stable and powerful magnetic nanoparticle supported Schiff base-palladium(II) (MNPs@SB-Pd) nanomagnetic catalyst was synthesized. The structural feature of the MNPs@SB-Pd nanomagnetic catalyst was properly characterized using a combination of attenuated total reflectance infrared spectroscopy (ATR-IR), ultraviolet–visible spectroscopy (UV–Visible), inductively coupled plasma-atomic emission spectroscopy (ICP-AES), energy-dispersive X-ray spectroscopy (EDS), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), thermogravimetric analysis (TGA) and Brunauer-Emmett-Teller surface area analysis (BET). The air- and moisture stable prepared MNPs@SB-Pd nanomagnetic catalyst was applied in C–C bond formation through Suzuki-Miyaura cross-coupling reactions and reduction of nitroarenes. Use of green medium, eco-friendly, waste-free, efficient preparation leading to high yield of products, short reaction time and cost effective catalyst are the major benefits of the method presented. In addition, the MNPs@SB-Pd nanomagnetic catalyst was easily separated from the reaction mixture with the help of an external magnetic field and reused for five consecutive cycles in Suzuki-Miyaura cross-coupling and ten consecutive cycles in reduction of nitroarene reactions with no significant loss of catalytic efficiency.
- Kandathil, Vishal,Koley, Tuhin S.,Manjunatha,Dateer, Ramesh B.,Keri, Rangappa S.,Sasidhar,Patil, Shivaputra A.,Patil, Siddappa A.
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- CuIBiOI is an efficient novel catalyst in Ullmann-type CN– couplings with wide scope—A rare non-photocatalyic application
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Preparation of a new, mixed-cationic layered CuIBiOI was prepared and its non-photocatalytic catalytic properties were explored. This solid substance had BiOI-like, lamellar and deflected structure resulting from CuI ion incorporation in the Bi2O2 layers. The as-prepared substance was fully characterized by XRD, Raman, far IR, UV–DR, XP spectroscopies, thermal (TG-DTG) and analytical (ICP-MS, SEM-EDX) methods, electron microscopies (SEM, TEM) as well as BET surface area measurements. By performing Ullmann-type CN– coupling reactions between aryl halides and aqueous ammonia, its catalytic capabilities were tested. The effects of solvents, added base and catalyst loading as well as reaction time and reaction temperature were scrutinized, and a green way for the reaction was identified. The recyclability of the catalyst without the loss of activity and its general applicability for a wide range of aryl halides were also demonstrated.
- Djerdj, Igor,Kónya, Zoltán,Kocsis, Marianna,Kukovecz, ákos,Pálinkó, István,Sipos, Pál,Varga, Gábor
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- Highly dispersed Au, Ag and Cu nanoparticles in mesoporous SBA-15 for highly selective catalytic reduction of nitroaromatics
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This paper demonstrates a homogeneous dispersion of 4 wt% coinage metal nanoparticles (Au, Ag and Cu) of different morphologies in the pores (～8 nm) of 3-aminopropyltriethoxysilane (APTES) modified mesoporous SBA-15 for selective catalytic reduction of m-dinitrobenzene to phenylenediamine. EDX, elemental mapping and HR-TEM analysis confirmed the uniform dispersal of metal nanoparticles within the mesoporous matrix having lattice fringes with a d-spacing of 0.232 nm for Au (111), 0.23 nm and 0.20 nm for Ag (111) and (200) and 0.25 nm for CuO (111) planes. XPS results illustrated the presence of Au and Ag in their metallic states whereas Cu was oxidized to CuO. XRD, TEM and surface area analysis revealed that formation of metal nanoparticles within the sieves led to a significant change in the surface structural and physicochemical properties. Metal nanospheres with increasing size i.e., ～5 nm (Au) 2 g-1), exhibited the best catalytic activity for m-dinitrobenzene reduction (k = 1.765 × 10-1 min-1) with 89% selectivity to m-phenylenediamine.
- Sareen, Shweta,Mutreja, Vishal,Singh, Satnam,Pal, Bonamali
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- Chemoselective transfer hydrogenation reactions over calcined-layered double hydroxides
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Layered double hydroxides (LDH) of the hydrotalcite type (also known as anionic clays) could be utilized as precursors of mixed metal oxides with pronounced basic properties. Upon calcination in air at ~ 723 K, these materials give rise to solid solutions between M2+ and M3+ ions (Mg2+, Mn2+, Co2+, Ni2+, Cu2+, Zn2+, and Al3+, Fe3+, Cr3+, respectively). The function of such materials was studied in the reduction of nitrobenzene to aniline using isopropanol as a hydrogen donor, and in the hydrogen-transfer reduction of p-chloronitrobenzene, p-nitroanisole, o-nitrotoluene, m-dinitrobenzene, acetophenone, benzophenone, p-nitroacetophenone, p-nitrobenzophenone, and cinnamaldehyde. The NiII-AlIII (mole ratio = 3:1) catalyst was very active in bringing about chemoselective reduction compared to other calcined LDH.
- Jyothi,Talawar,Raja,Sreekumar,Rajagopal,Rao
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- Internally Supported Metal-Oxide Nanocatalyst for Hydrogenation of Nitroaromatics
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The uncalcined but highly dispersive oxide-supported metal catalyst for liquid phase reactions may suffer from the agglomeration of metal nanoparticles and the drop of metal catalyst in solution, which will decrease the activity and shorten their life in
- Wei, Bo,Sheng, Kefa,Ge, Jianping
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- Preparation, surface and crystal structure, band energetics, optoelectronic, and photocatalytic properties of AuxCd1-xS nanorods
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A series of novel AuxCd1-xS materials (x=0, 0.01, 0.02, 0.03, 0.05, 0.07, 0.1) were prepared and their optical properties, structural-surface morphology, and photocatalytic activity for oxidation and reduction reactions under visible-light irradiation were studied. X-ray diffraction confirmed the shrinkage of the hexagonal crystal structure of CdS; the lattice parameters decreased as a=4.190→4.072 ? and b=c=6.790→6.635 ? with increased loading (1-10 mol%) of the Au3+ dopant. Optical spectra of AuxCd1-xS revealed a significant red-shift (485→538 nm) of the absorption onset and band edge emission (506→530 nm) with notable quenching in photoluminescence. The bandgap energy decreases (2.71→2.41 eV) with increasing Au3+ doping of the CdS nanorods along with considerable shifting of valence band (+1.13→+1.04 eV) and conduction band positions (-1.58→-1.36 eV) versus NHE. The surface area of bare CdS (90.56 m2 g-1) is gradually reduced to 12.32 m2 g-1 with increasing Au3+ doping content. The photocatalytic activity considerably improves with doping, where the Au0.1Cd0.9S composite displays the highest levels of photooxidation (95%) of 0.5 mM salicyldehyde and reduction of 5 mM m-dinitrobenzene to m-nitroaniline (44 %) and m-phenylenediamine (52 %) relative to bare CdS (50 %) probably due to the homogeneous dispersion of Au3+ ions throughout CdS crystal, their superior band-energetics for facile charge-separation and better photostability.
- Singh, Rohit,Pal, Bonamali
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- Selective hydrogenation. II. m-Dinitrobenzene to m-nitroaniliine using palladium on carbon as catalyst
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In the present work m-dinitrobenzene (m-DNB) was hydrogenated to m-nitroaniline (m-NA) using palladium on carbon as catalyst. The reaction conditions were standardized to obtain m-NA with high selectivity. It was possible to obtain m-NA with 95% selectivity at 90% conversion and formation of m-phenylenediamine (m-PD) was restricted using suitable conditions. Kinetic studies of the reaction at different initial concentrations of substrate, catalyst loading, temperature, as well as pressure, were studied.
- Khilnani, Veena L.,Chandalia
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- Preparation of carbon supported CuPd nanoparticles as novel heterogeneous catalysts for the reduction of nitroarenes and the phosphine-free Suzuki-Miyaura coupling reaction
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This paper reports on the synthesis and use of CuPd nanoparticles supported on carbon, as highly active catalysts for the reduction of nitroarenes and Suzuki-Miyaura coupling reactions. The catalyst was characterized using the powder XRD, SEM, ICP-AES and EDS techniques. This method has the advantages of high yields, elimination of homogeneous catalysts, simple methodology and easy work up. Catalytic efficiency remains unaltered even after several repeated cycles.
- Nasrollahzadeh, Mahmoud,Jaleh, Babak,Ehsani, Ali
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- The colloidal synthesis of unsupported nickel-tin bimetallic nanoparticles with tunable composition that have high activity for the reduction of nitroarenes
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Abstract Ni-Sn bimetallic nanoparticles with controllable size and composition were prepared by facile method in ambient air using inexpensive metal salts. Adjusting stoichiometric ratio of Ni and Sn precursors afforded nanoparticles with different compositions, such as Ni100, Ni74-Sn26, Ni59-Sn41, and Ni50-Sn50. The characterization of nanoparticles was performed by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HR-TEM), and energy dispersive X-ray analysis (EDX). Ni75-Sn25 and Ni60-Sn40 nanoparticles showed enhanced catalytic activity towards 2-nitroaniline reduction as compared with Ni nanoparticles. Furthermore, Ni75-Sn25 nanocatalyst exhibited excellent activity for the reduction of a number of nitro aromatic compounds under mild conditions along with high level of reusability.
- Shah, Mazloom,Guo, Qing-Xiang,Fu, Yao
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- Excellent catalytic properties over nanocomposite catalysts for selective hydrogenation of halonitrobenzenes
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A partially reduced Pt/γ-Fe2O3 magnetic nanocomposite catalyst (Pt/γ-Fe2O3-PR) exhibited excellent catalytic properties in the selective hydrogenation of 2, 4-dinitrochlorobenzene and iodonitrobenzenes. The selectivity to 4-chloro-m-phenylenediamine (4-CPDA), meta-iodoaniline (m-IAN), and para-iodoaniline (p-IAN) reached 99.9%, 99.8%, and 99.4%, respectively, at complete conversion of the substrates. The hydrodehalogenation of 4-CPDA and IANs was fully suppressed for the first time over Pt/γ-Fe2O3-PR. It was found that CO chemisorption on the Pt nanoparticles deposited on the partially reduced γ-Fe2O3 and Fe3O4 nanoparticles was very weak, implying a weak tendency of the electronic back-donation from the Pt nanoparticles to the π* antibonding orbitals of the adsorbed molecules. We believe that this is a cause of the superior selectivity to the haloanilines in the hydrogenation reactions of interest over the Pt/γ-Fe2O3-PR catalyst.
- Liang, Minghui,Wang, Xiaodong,Liu, Hongquan,Liu, Haichao,Wang, Yuan
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- Industrial Cunninghamia lanceolata carbon supported FeO(OH) nanoparticles-catalyzed hydrogenation of nitroarenes
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The development of green and efficient methods for hydrogenation of nitroarenes is still highly demanding in organic synthesis. Herein, we report an industrial Cunninghamia lanceolata carbon supported FeO(OH) nanoparticles process for the synthesis of aryl amines with good yields via hydrogenation of nitroarenes. Nine key anti-cancer drug intermediates were successfully achieved with protocol. And Osimertinib intermediate 4m can be smoothly synthesized at a 2.67 kg-scale with >99.5% HPLC purity. This protocol features cheap carbon source, highly catalytic activity, simple operation, kilogram-scalable and recyclable catalysts (eight times without observable losing activity).
- Fu, Lihua,Li, Dingzhong,Lu, Hao,Qiu, Renhua,Sun, Tulai,Xing, Chen,Yang, Tianbao
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- Rhodium nanoparticles supported on 2-(aminomethyl)phenols-modified Fe3O4 spheres as a magnetically recoverable catalyst for reduction of nitroarenes and the degradation of dyes in water
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A magnetic nanostructured catalyst (Fe3O4@SiO2-Amp-Rh) modified with 2-(aminomethyl)phenols (Amp) was designed and prepared, which is used to catalyze the reduction of aromatic nitro compounds into corresponding amines and the degradation of dyes. The 2-aminomethylphenol motif plays a vital role in the immobilization of rhodium nanoparticles to offer extraordinary stability, which has been characterized by using various techniques, including transmission electron microscopy (TEM), thermal gravimetric analyzer (TGA), X-Ray Diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). A variety of nitroaromatic derivatives have been reduced to the corresponding anilines in water with up to yields of 99% within 1?h at room temperature. In addition, the catalyst system is effective in catalyzing the reduction of toxic pollutant 4-nitrophenol and the degradation of MO, MB and RhB dyes. Importantly, this catalyst Fe3O4@SiO2-Amp-Rh can be easily recovered by an external magnetic field because of the presence of magnetic core of Fe3O4, and the activity of Fe3O4@SiO2-Amp-Rh does not decrease significantly after 7 times’ recycling, which indicates that the catalyst performed high reactivity as well as stability. Graphical abstract: [Figure not available: see fulltext.]
- Chen, Tian,Chen, Zhangpei,Hu, Jianshe,Lv, Kexin,Reheman, Aikebaier,Wang, Gongshu
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- Magnetically‐recoverable Schiff base complex of Pd(II) immobilized on Fe3O4@SiO2 nanoparticles: an efficient catalyst for the reduction of aromatic nitro compounds to aniline derivatives
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Fe3O4@SiO2/Schiff base/Pd(II) is reported as a magnetically recoverable heterogeneous catalyst for the chemoselective reduction of aromatic nitro compounds to the corresponding amines through catalytic transfer hydrogenation (CTH). In this regard, a small amount of the nanocatalyst (0.52?mol% Pd) and hydrazine hydrate, showing safe characteristics and perfect ability as the hydrogen donor, were added to the nitro substrates. The experiments described the successful reduction of aromatic nitro compounds with good to excellent yields and short reaction times. The catalyst, due to its magnetic property, could be simply separated from the reaction mixture by a permanent magnet and reused in seven consecutive reactions without considerable loss in its activity. Moreover, the leaching of Pd was only 3.6% after the seventh run. Thus, the most striking feature of this method is to use a small amount of the magnetic nanocatalyst along with a cheap and safe hydrogen source to produce the important amine substances selectively, which makes the method economical, cheap, environmentally friendly, and simple. Graphic abstract: [Figure not available: see fulltext.]
- Azadi, Sedigheh,Esmaeilpour, Mohsen,Sardarian, Ali Reza
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p. 809 - 821
(2021/07/20)
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- Copper nanoparticles (CuNPs) catalyzed chemoselective reduction of nitroarenes in aqueous medium
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Abstract: A procedure for practical synthesis of CuNPs from CuSO4·5H2O is established, under appropriate reaction conditions, using rice (Oryza sativa) as an economic source of reducing as well as a stabilizing agent. Optical and microscopic techniques are employed for the characterization of the synthesized CuNPs and the sizes of the particles were found to be in the range of 8 ± 2 nm. The nanoparticles are used as a catalyst for chemoselective reduction of aromatic nitro compounds to corresponding amines under ambient conditions and water as a reaction medium. Graphic abstract: CuNPs are synthesized using hydrolysed rice and used as catalyst for chemoselective reduction of nitroarenes to their corresponding amines in water. [Figure not available: see fulltext.]
- Chand, Dillip Kumar,Rai, Randhir
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- Rhodium-terpyridine Catalyzed Transfer Hydrogenation of Aromatic Nitro Compounds in Water
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A rhodium terpyridine complex catalyzed transfer hydrogenation of nitroarenes to anilines with i-PrOH as hydrogen source and water as solvent has been developed. The catalytic system can work at a substrate/catalyst (S/C) ratio of 2000, with a turnover frequency (TOF) up to 3360 h?1, which represents one of the most active catalytic transfer hydrogenation systems for nitroarene reduction. The catalytic system is operationally simple and the protocol could be scaled up to 20 gram scale. The water-soluble catalyst bearing a carboxyl group could be recycled 15 times without significant loss of activity.
- Liu, Yuxuan,Miao, Wang,Tang, Weijun,Xue, Dong,Xiao, Jianliang,Wang, Chao,Li, Changzhi
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supporting information
p. 1725 - 1729
(2021/06/01)
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- Chemoselective reduction of nitroarenes, N-acetylation of arylamines, and one-pot reductive acetylation of nitroarenes using carbon-supported palladium catalytic system in water
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Developing and/or modifying fundamental chemical reactions using chemical industry-favorite heterogeneous recoverable catalytic systems in the water solvent is very important. In this paper, we developed convenient, green, and efficient approaches for the chemoselective reduction of nitroarenes, N-acetylation of arylamines, and one-pot reductive acetylation of nitroarenes in the presence of the recoverable heterogeneous carbon-supported palladium (Pd/C) catalytic system in water. The utilize of the simple, effective, and recoverable catalyst and also using of water as an entirely green solvent along with relatively short reaction times and good-to-excellent yields of the desired products are some of the noticeable features of the presented synthetic protocols. Graphic abstract: [Figure not available: see fulltext.].
- Zeynizadeh, Behzad,Mohammad Aminzadeh, Farkhondeh,Mousavi, Hossein
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p. 3289 - 3312
(2021/05/11)
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- Crosslinked polymer encapsulated palladium nanoparticles for catalytic reduction and Suzuki reactions in aqueous medium
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Acrylamide and N-isopropylacrylamide were copolymerized in the presence of a N,N-methylenebisacrylamide crosslinker to obtain poly(N-isopropylacrylamide-co-acrylamide) [P(NA)] polymer colloidal particles. Pd nano crystals with diameter of 4–8 nm were loaded into the [P(NA)] microgels by reduction of [PdCl4]-2 within dispersion of polymer microgels. The Pd NPs-loaded hybrid microgels were analysed by TEM, STEM, EDX and XRD. The catalytic ability of the Pd-[P(NA)] system was investigated towards reductive transformation of nitroarenes into corresponding aryl amines and Suzuki coupling transformation in a green solvent, H2O. The progress of catalytic reaction was examined by thin layer chromatography (TLC). Different reactants were effectively converted into their corresponding products with great to fabulous yields (extending from 75 to 97%) under gentle reaction conditions. The Pd-[P(NA)] catalyst is stable for long time and can be utilized numerous times without any notable loss in its catalytic action.
- Begum, Robina,Farooqi, Zahoor H.,Xiao, Jianliang,Ahmed, Ejaz,Sharif, Ahsan,Irfan, Ahmad
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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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- Highly efficient N-doped carbon supported FeSx-Fe2O3 catalyst for hydrogenation of nitroarenes via pyrolysis of sulfurized N,Fe-containing MOFs
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Integrating MOFs as precursor, especially for employing N-containing organic linkers, with sulfides is an effective method to prepare the highly efficient N-doped carbon supported metal-based catalysts for hydrogenation of nitroarenes. In this work, a N,Fe-containing metal organic frameworks (MOFs; termed as MIL88-HMTA) with spindle-like structure was prepared via self-assembly method, in which hexamethylenetetramine (HMTA) linker was introduced as N source. Subsequently, N-doped carbon supported FeSx-Fe2O3 catalyst (named FeSx-Fe2O3@CN) was fabricated upon the pyrolysis of sulfurized MIL88-HMTA. Catalytic experiments reveal that the FeSx-Fe2O3@CN delivered excellent performance for hydrogenation of nitroarenes in comparison with those of catalyst without sulfidation process (Fe2O3@CN) and conventional MIL88 derived catalyst (Fe2O3@C). The XRD, TEM, SEM/EDX, Raman, UV, and XPS analyses have revealed that the developed FeSx-Fe2O3@CN catalyst exhibited outstanding catalytic efficiency was ascribed to synergistic effect between FeSx and Fe2O3 species, abundant structural defects, more Fe-Nx species, and strengthened decomposition ability of hydrazine hydrate (N2H4?H2O). Furthermore, the effect of sulfidation ratio (the mass ratio between thioacetamide and MIL88-HMTA) towards preparation of the developed FeSx-Fe2O3@CN on the catalytic activity of hydrogenation reaction was also systematically performed. Notably, the optimized catalyst (denoted as FeSx-Fe2O3@CN-8) exhibited unexpected performance and recyclability for hydrogenation of nitroarenes under mild condition. The pyrolysis of sulfurized N-containing MOFs may present a facile approach for fabricating MOFs-derived N-doped carbon supported catalysts, which provides a potential application in heterogeneous catalytic reactions.
- Li, Xuewei,She, Wei,Wang, Jing,Li, Weizuo,Li, Guangming
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- UiO-66/btb/Pd as a stable catalyst reduction of 4-nitrophenol into 4-aminophenol
-
In order to synthesize highly sparse nanoparticles, UiO-66-NH2 can be utilized as an appropriate support. It has great surface area, which is functionalized by 1,3-bis(dimethylthiocarbamoyloxy)benzene compounds that can act as the powerful performers, hence, the Pd (II) is a complex without aggregate over the UiO-66-NH2 microspheres structures (UiO-66/btb/Pd). Nitro-aromatic pollution in industrial waste streams threat wellbeing of water resources. The produced UiO-66/btb/Pd nanocatalyst showed appropriate catalytic activity for reduce nitro-aromatic compounds in aqueous solution. XRD, EDS, SEM, FT-IR, and TEM were utilized for characterizing the nanostructures UiO-66/btb/Pd.
- Kiani, Zahra,Zhiani, Rahele,Khosroyar, Susan,Motavalizadehkakhky, Alireza,Hosseiny, Malihesadat
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- Highly efficient hydrogenation reduction of aromatic nitro compounds using MOF derivative Co-N/C catalyst
-
The direct hydrogenation reduction of aromatic nitro compounds to aromatic amines with non-noble metals is an attractive area. Herein, the pyrolysis of Co(2-methylimidazole)2 metal-organic framework successfully produces a magnetic Co-N/C nanocomposite, which exhibits a porous structure with a high specific area and uniform Co nanoparticle distribution in nitrogen-doped graphite. In addition, the Co-N/C catalysts possess high cobalt content (23%) with highly active β-Co as the main existing form and high nitrogen content (3%). These interesting characteristics endow the Co-N/C nanocomposite with excellent catalytic activity for the hydrogenation reduction of nitro compounds under mild conditions. In addition, the obtained Co-N/C nanocomposites possess a broad substrate scope and good cycle stability for the reduction of halogen-substituted or carbonyl substituted phenyl nitrates. This journal is
- Dai, Yuyu,Li, Xiaoqing,Wang, Likai,Xu, Xiangsheng
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p. 22908 - 22914
(2021/12/24)
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- Novel environment-friendly production process for preparing amine product and H - acid through silane chemical reduction of several nitro compounds
-
The invention relates to the field of new materials for fine chemicals, and relates to a reduction reaction of a series of nitro compounds, in particular to m-nitroaniline. Several particular important amine compounds such as m-phenylenediamine, 5 - amino o-cresol, 2 - methyl p-phenylenediamine, 1/2 - naphthylamine, H - acid amine and 2, 4, 6 - trimethyl-M-phenylenediamine are prepared from the corresponding mono-or double-nitro compound precursors with a new environmental protection production process technology of and acids derived from the novel process technology. H.
- -
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Paragraph 0027-0033
(2021/09/08)
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- Highly porous copper-supported magnetic nanocatalysts: made of volcanic pumice textured by cellulose and applied for the reduction of nitrobenzene derivatives
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Herein, a novel designed heterogeneous catalytic system constructed of volcanic pumice magnetic particles (VPMPs), cellulose (CLS) as a natural polymeric matrix, and copper nanoparticles (Cu NPs) is presented. Also, to enhance the inherent magnetic property of VPMP, iron oxide (Fe3O4) nanoparticles have been prepared and incorporated in the structureviaanin situprocess. As its first and foremost excellent property, the designed composite is in great accordance with green chemistry principles because it contains natural ingredients. Another brilliant point in the architecture of the designed composite is the noticeable porosity of VPMP as the core of the composite structure (surface area: 84.473 m2g?1). This great porosity leads to the use of a small amount (0.05 g) of the particles for catalytic purposes. However, the main characterization methods, such as Fourier-transform infrared and energy-dispersive X-ray spectroscopy, thermogravimetric analysis, and electron microscopy, revealed that the spherical metallic particles (Fe and Cu oxides) were successfully distributed onto the surface of the VPMP and CLS matrices. Further, vibrating-sample magnetometer analysis confirmed the enhancement of the magnetic property (1.5 emu g?1) of the composite through the addition of Fe3O4nanoparticles. Further, the prepared (Fe3O4@VPMP/CLS-Cu) nanocomposite has been applied to facilitate the reduction reaction of hazardous nitrobenzene derivatives (NBDs) to their aniline analogs, with 98% conversion efficiency in eight minutes under mild conditions. Moreover, the good reusability of the catalytic system has been verified after recycling it ten times without any significant decrease in the performance.
- Fazeli, Atefeh,Maleki, Ali,Qazi, Fateme Sadat,Saeidirad, Mahdi,Shalan, Ahmed Esmail,Taheri-Ledari, Reza
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p. 25284 - 25295
(2021/08/05)
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- Synthesis of CoFe2O4@Pd/Activated carbon nanocomposite as a recoverable catalyst for the reduction of nitroarenes in water
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Efficient reduction of nitro compounds into amines is an important industrial transformation. So, it is a great deal to design new catalysts for efficient reduction of the nitro compounds especially in water. In this work, a new magnetic Pd/activated carbon nanocomposite (CoFe2O4@Pd/AC) was synthesized via metal-impregnation-pyrolysis method. The CoFe2O4@Pd/AC was fully characterized by FT-IR, PXRD, FESEM, TEM, VSM, EDX-mapping and BET techniques. The results showed that CoFe2O4@Pd/AC is a highly reactive and easily recoverable magnetic catalyst for the reduction of the nitro compounds by using NaBH4 in water. For instance, aniline was obtained in high yield (99%) after 75 ?min at 25 ?C by using just 6 ?mg of the catalyst. In addition, CoFe2O4@Pd/AC was recovered by a simple magnetic decantation and it exhibits stable activity and remains intact during the catalytic process with no significant loss in activity (8 cycles).
- Hamadi, Hosein,Kazeminezhad, Iraj,Mohammadian, Sara
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-
- Activated Mont K10-Carbon supported Fe2O3: A versatile catalyst for hydration of nitriles to amides and reduction of nitro compounds to amines in aqueous media
-
The iron oxide was successfully supported on activated clay/carbon through an experimentally viable protocol for both hydrations of nitrile to amide and reduction of nitro compounds to amines. The as-prepared catalyst has been extensively characterised by XPS, SEM-EDX, TEM, TGA, BET surface area measurements and powdered X-ray diffraction (PXRD). A wide variety of substrates could be converted to the desired products with good to excellent yields by using water as a green solvent for both the reactions. The catalyst was recyclable and reusable up to six consecutive cycles without compromising its catalytic proficiency. Graphical abstract: Activated Mont K10 carbon-supported Fe2O3 is a very efficient and versatile heterogeneous catalytic system for hydration of nitriles to amides and reduction of nitro compounds to amines and can be reused up to six consecutive cycles without significant loss in catalytic activity.[Figure not available: see fulltext.].
- Rahman, Taskia,Borah, Geetika,Gogoi, Pradip K
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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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- Au/Ni/Ni(OH)2/C Nanocatalyst with High Catalytic Activity and Selectivity for m-dinitrobenzene Hydrogenation
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The Au/Ni/Ni(OH)2/C bimetallic nanocatalysts with different Au loadings (Au/Ni/Ni(OH)2/C-1: 0.05 wt%Au; Au/Ni/Ni(OH)2/C-2: 0.46 wt%Au; Au/Ni/Ni(OH)2/C-3: 2.60 wt%Au) were prepared at room temperature. The characterization results proved the nanostructure of Au islands supported on the Ni/Ni(OH)2 nanoparticles (NPs) and synergy effect of Au-, Ni- and Ni(OH)2-related species in Au/Ni/Ni(OH)2/C. These are the main reasons why their catalytic performance and selectivity to m-nitroaniline in m-dinitrobenzene hydrogenation were much higher than those of monometallic catalysts (Au/C and Ni/Ni(OH)2/C). Because Au/Ni/Ni(OH)2/C-2 was with high dispersion of Au, Au(0)/Aun+ ratio≈1:1 on the surface, novel nanostructure, moderate capacity of activating and dissociating hydrogen, and synergistic effect, it had much better catalytic activity (conversion of m-dinitrobenzene-100%) and higher selectivity to m-nitroaniline (95.0%) in m-dinitrobenzene hydrogenation reaction compared to other two supported bimetallic catalysts (Au/Ni/Ni(OH)2/C-1 and Au/Ni/Ni(OH)2/C-3). Au/Ni/Ni(OH)2/C-2 also exhibited high stability. Graphic abstract: [Figure not available: see fulltext.]
- Ruan, Luna,Fu, Huan,Liao, Jianhua,Ding, Nengwen,Lan, Junjie,Yang, Kai,Rong, Mengke,Zhao, Ning,Zhu, Lihua,Chen, Bing Hui
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- Yeast supported gold nanoparticles: an efficient catalyst for the synthesis of commercially important aryl amines
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Candida parapsilosisATCC 7330 supported gold nanoparticles (CpGNP), prepared by a simple and green method can selectively reduce nitroarenes and substituted nitroarenes with different functional groups like halides (-F, -Cl, -Br), olefins, esters and nitriles using sodium borohydride. The product aryl amines which are useful for the preparation of pharmaceuticals, polymers and agrochemicals were obtained in good yields (up to >95%) using CpGNP catalyst under mild conditions. The catalyst showed high recyclability (≥10 cycles) and is a robust free flowing powder, stored and used after eight months without any loss in catalytic activity.
- Krishnan, Saravanan,Patel, Paresh N.,Balasubramanian, Kalpattu K.,Chadha, Anju
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supporting information
p. 1915 - 1923
(2021/02/06)
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- Method for preparing M-phenylenediamine based on continuous catalytic hydrogenation of fixed bed microreactor
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The method comprises the following steps: (1) taking dinitrochlorobenzene as a raw material and dissolving it in a solvent as a substrate solution to be hydrogenated. The dinitrochlorobenzene is at least one of 2, 4 -dinitrochlorobenzene, 2,6 -nitrochlorobenzene and 3,5 -dinitrochlorobenzene. (2) The substrate solution to be hydrogenated is mixed with hydrogen into a micro mixer to form a gas-liquid mixture with good gas-liquid micro-dispersion state, and then the reaction is carried out in a micro-packed bed reactor filled with a solid particle catalyst. The reaction temperature was 40 - 160 °C and the pressure was 1 - 5 mpa. The residence time of the gas-liquid mixture in the microfilled bed reactor was 10 - 120s. (3) The gas-liquid mixture obtained after the completion of the reaction is subjected to gas-liquid separation, and the liquid product enters a subsequent separation and purification system.
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Paragraph 0046-0047; 0052-0055; 0058-0059
(2021/09/26)
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- Preparation method of a plurality of (hetero) aromatic polyamines
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The invention relates to the field of organic functional new material chemicals, and discloses a novel process technology for preparing a plurality of (hetero) aromatic polyamines through corresponding (hetero) aromatic polyfunctional hydroxamic acids (hydroxamic acid) before (re-arrangement). These (hetero) aromatic polyamines are well-known dyes and pigment and pharmaceutical pesticide-related fields of very wide range of critical fine chemical materials.
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Paragraph 0018-0022; 0024-0026; 0028-0030; 0032-0034; ...
(2021/09/15)
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- Selective primary aniline synthesis through supported Pd-catalyzed acceptorless dehydrogenative aromatization by utilizing hydrazine
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By utilizing hydrazine (N2H4) as the nitrogen source in the presence of a hydroxyapatite-supported Pd nanoparticle catalyst (Pd/HAP), various primary anilines can be selectively synthesized from cyclohexanonesviaacceptorless dehydrogenative aromatization. The strong nucleophilicity of N2H4and the stability of the hydrazone intermediates can effectively suppress the formation of the undesired secondary aniline byproducts.
- Lin, Wei-Chen,Yamaguchi, Kazuya,Yatabe, Takafumi
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supporting information
p. 6530 - 6533
(2021/07/07)
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- METHOD FOR PRODUCING AMINO AROMATIC COMPOUND
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To provide a novel method for producing an amino aromatic compound.SOLUTION: A method for producing a compound (B) having at least one amino group on an aromatic ring, includes at least a step in which a compound (A) at least having an aromatic ring and one group represented by -CR=CH2 [R is a hydrogen atom or a C1-3 alkyl group] on the aromatic ring is reacted with sodium azide in the presence of acid.SELECTED DRAWING: None
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-
Paragraph 0040-0045
(2021/03/03)
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- Synthesis method of high-quality M-phenylenediamine
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The invention belongs to the technical field of petrochemical organic synthesis, and particularly relates to a synthesis method of high-quality m-phenylenediamine. The method comprises steps: taking isophthalonitrile, anhydrous sodium carbonate and hydrogen peroxide as raw materials, and synthesizing isophthalimide under the action of a catalyst; and reacting isophthalimide with sodium hypochlorite, and after the reaction is finished, adding an antioxidant into the reaction product to carry out post-treatment, thereby obtaining m-phenylenediamine. The method has the advantages of simple synthesis process, simple post-treatment, effective solving of the problems of easy oxidation and low quality of resorcinol, realization of the yield of 95% or above and the purity of 99% or above, great reduction of the production cost, and meeting of the market demands of high-quality resorcinol.
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Paragraph 0018; 0020-0021; 0022; 0024-0025; 0026; 0028-0029
(2021/01/30)
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- Preparation method of M-phenylenediamine
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The invention belongs to the technical field of petrochemical organic synthesis, and particularly relates to a preparation method of m-phenylenediamine. According to the invention, m-phthalonitrile isused as a reaction raw material, and m-phenylenediamine is prepared through two steps of reactions of catalytic hydrolysis amidation and Hofmann degradation. According to the method, the key technical problems that in the process of producing m-phenylenediamine through benzene nitration and hydrogenation in a traditional process, due to the fact that dangerous processes of nitration and hydrogenation are involved, potential safety hazards in the production process are large, and the environment is polluted are solved, nitration and hydrogenation reactions are not involved in the process, thereaction temperature is low, reaction is mild, control is easy, the yield reaches 80% or above, and product purity reaches 95% or above.
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-
Paragraph 0006; 0016; 0018; 0019; 0021; 0022; 0024; 0025
(2021/02/10)
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- Cycloglutaramide-based ligand, synthetic method of ligand, application of ligand in coupling reaction for synthesizing arylamine derivative and catalytic system
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The invention discloses a cycloglutaramide-based ligand having a general formula I shown in the specification, a synthetic method of the ligand, an application of the ligand in a coupling reaction forsynthesizing an arylamine derivative, and a catalytic system. The compounds represented by the formula I can be used as a ligand in the coupling reaction of synthesizing the arylamine derivative by using an aryl halide under catalysis of copper, especially the coupling reaction of aryl halide and an amine source to form a C-N bond under catalysis. Under mild reaction conditions, the high-yield arylamine derivative is obtained, and the ligand has a simple structure, convenient preparation and a less use amount.
- -
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Paragraph 0106; 0107; 0108; 0109; 0110
(2020/03/12)
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- Tin(ii) chloride dihydrate/choline chloride deep eutectic solvent: Redox properties in the fast synthesis of: N -arylacetamides and indolo(pyrrolo)[1,2- a] quinoxalines
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In this contribution a physicochemical, IR and Raman characterization for the tin(ii) chloride dihydrate/choline chloride eutectic mixture is reported. The redox properties of this solvent were also studied by cyclic voltammetry finding that it can be successfully used as an electrochemical solvent for electrosynthesis and electroanalytical processes and does not require negative potentials as verified by the reduction of nitrobenzene. The potential use of this eutectic mixture as a redox solvent was further explored in obtaining aromatic amines and N-arylacetamides starting from a wide variety of nitroaromatic compounds. In addition, a fast synthetic strategy for the construction of a series of indolo(pyrrolo)[1,2-a]quinoxalines was developed by reacting 1-(2-nitrophenyl)-1H-indole(pyrrole) with aldehydes. This simple protocol offers a straightforward method for the construction of the target quinoxalines in short reaction times and high yields where the key step involves a tandem one-pot reductive cyclization-oxidation.
- Bejarano, Oscar Rodríguez,Ochoa-Puentes, Cristian,Pe?a-Solórzano, Diana,Trujillo, Sergio Alfonso
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p. 40552 - 40561
(2020/11/18)
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- The immobilized Cu nanoparticles on magnetic montmorillonite (MMT?Fe3O4?Cu): As an efficient and reusable nanocatalyst for reduction and reductive-acetylation of nitroarenes with NaBH4
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In this study, the immobilization of copper nanoparticles on superparamagnetic montmorillonite, MMT?Fe3O4?Cu, was studied. Magnetically nanoparticles (MNPs) of iron oxide (Fe3O4) were primarily prepared by a chemical co-precipitation method. Next, the prepared Fe3O4 MNPs were intercalated within the interlamellar spaces and external surface of sodium-exchanged montmorillonite. Finally, Cu NPs were immobilized on magnetic montmorillonite by a simply mixing of an aqueous solution of CuCl2·2H2O with MMT?Fe3O4 followed by the reduction with NaBH4. Characterization of MMT?Fe3O4 clay system represented that through the immobilization of Fe3O4 MNPs, disordered-layers structure of MMT was easily reorganized to an ordered-layers arrangement. The synthesized composite systems were characterized using FT-IR, SEM, EDX, XRD, VSM, BET and ICP-OES analyses. SEM analysis exhibited that dispersion of Cu NPs, with the size distribution of 15–25 nm, on the surface of magnetic clay was taken place perfectly. BET surface analysis indicated that after the immobilization of Fe3O4 and Cu species, the surface area and total pore volume of MMT?Fe3O4?Cu system was decreased. Next, the Cu-clay nanocomposite system showed a perfect catalytic activity towards reduction of nitroarenes to anilines as well as reductive-acetylation of nitroarenes to acetanilides using NaBH4 and Ac2O in water as a green and economic solvent. The copper magnetic clay catalyst can be easily separated from the reaction mixture by an external magnetic field and reused for six consecutive cycles without the significant loss of its catalytic activity.
- Zeynizadeh, Behzad,Rahmani, Soleiman,Tizhoush, Hengameh
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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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-
- Synthesis and characterization of go-chit-ni nanocomposite as a recoverable nanocatalyst for reducing nitroarenes in water
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In the present study, nickel nanoparticles (Ni-NPs) immobilized on graphene oxide-chitosan (GO-Chit-Ni) have been synthesized and characterized as a catalyst for reduction of nitroarenes in water. For this purpose, GO has been functionalized with chitosan (GO-Chit). Then, Ni-NPs were immobilized on the surface of GO-Chit using a simple method. The GO-Chi-Ni nanocomposites were characterized using Fourier Transforms Infrared Spectroscopy (FT-IR), Transmission Electron Microscopy (TEM), X-Ray Diffraction Measurements (XRD), and Atomic Adsorption Spectrometry (AAS). The GO-Chi-Ni nanoparticles demonstrated appropriate catalytic activity in reducing nitroarenes to aryl amines in the existence of sodium borohydride (NaBH4) aqueous solution as a hydrogen source at 80oC. This catalytic system applies environmentally benign water as a solvent that is cheap, easily accessible, non-toxic, non-volatile, non-flammable and thermally stable. This type of catalyst can be applied several times with no considerable change in its performance.
- Azadi, Roya,Sarvestani, Mosayeb
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p. 523 - 531
(2020/07/17)
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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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- Immobilized N-Heterocyclic Carbene-Palladium(II) Complex on Graphene Oxide as Efficient and Recyclable Catalyst for Suzuki–Miyaura Cross-Coupling and Reduction of Nitroarenes
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Abstract: A new and efficient N-heterocyclic carbene (NHC)-palladium(II) complex immobilized on graphene oxide (NHC-Pd@GO) has been successfully designed and synthesized. The prepared NHC-Pd@GO heterogeneous catalyst was fully characterized using a combination of fourier transform infrared spectroscopy (FTIR), inductively coupled plasma-optical emission spectroscopy (ICP-OES), energy-dispersive X-ray spectroscopy (EDS), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), thermogravimetric analysis (TGA) and Brunauer–Emmett–Teller surface area analysis (BET). This new air- and moisture-stable NHC-Pd@GO heterogeneous catalytic system was found to be a highly active catalyst in the Suzuki–Miyaura cross-coupling between phenylboronic acid and various aryl halides (bromides/chlorides/iodides) and in the reduction of nitroarenes. These organic transformations were best performed in an aqueous ethanol and aqueous methanol solvent system respectively with low catalyst loading under mild reaction conditions. Furthermore, NHC-Pd@GO heterogeneous catalyst could be recovered easily and reused at least eleven times in Suzuki–Miyaura cross-coupling and nine times in reduction of nitroarenes without any considerable loss of its catalytic activity. The stability and good selectivity of the NHC-Pd@GO heterogeneous catalyst in recycling experiments signify that it could be useful for practical application in various organic transformations. Graphic Abstract: [Figure not available: see fulltext.].
- Kandathil, Vishal,Kulkarni, Bhakti,Siddiqa, Aisha,Kempasiddaiah, Manjunatha,Sasidhar,Patil, Shivaputra A.,Patil, Siddappa A.
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p. 384 - 403
(2020/01/06)
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- Method for reducing aromatic nitro compounds into aromatic amine compounds
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The invention discloses a method for reducing aromatic nitro compounds into aromatic amine compounds. The aromatic nitro compounds are reacted at a temperature of 110-130 DEG C in an inert or air atmosphere under the action of a rhodium catalyst by using water as a solvent, isopropanol as a hydrogen source and potassium phosphate or sodium carbonate as an alkali to obtain the aromatic amine compounds. The method has the advantages of simplicity in operation, greenness, environmental friendliness, reduction of environmental pollution, high reaction yield, amplified gram-scale preparation of theamine compounds, high catalyst activity, recyclability and low industrial production cost.
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Paragraph 0022-0023
(2020/03/25)
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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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- Preparation method of phenylenediamine (by machine translation)
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The preparation method comprises the following steps: in the presence of an organic solvent and a catalyst, taking dihalobenzene as a raw material, ammonia water as an ammonia solution, heating ammonolysis reaction under a low pressure of no more than 0.2 mpa to prepare phenylenediamine, wherein the complex metal ion is selected from Pd. 2 + Ni-Zn-Ni alloy2 + Ni, Co2 + Fe-Fe-B2 + Or Cu2 + At least one of the. In addition, the reaction process avoids the use of a mixed acid compound harmful to the environment, is green and environment-friendly, can be recycled, reduces the production cost and is beneficial to large-scale preparation. (by machine translation)
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Paragraph 0071-0072
(2020/11/23)
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- Sustainable Hydrogenation of Nitroarenes to Anilines with Highly Active in-situ Generated Copper Nanoparticles
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Metal nanoparticles (NPs) are usually stabilized by a capping agent, a surfactant, or a support material, to maintain their integrity. However, these strategies can impact their intrinsic catalytic activity. Here, we demonstrate that the in-situ formation of copper NPs (Cu0NPs) upon the reduction of the earth-abundant Jacquesdietrichite mineral with ammonia borane (NH3BH3, AB) can provide an alternative solution for stability issues. During the formation of Cu0NPs, hydrogen gas is released from AB, and utilized for the reduction of nitroarenes to their corresponding anilines, at room temperature and under ambient pressure. After the nitroarene-to-aniline conversion is completed, regeneration of the mineral occurs upon the exposure of Cu0NPs to air. Thus, the hydrogenation reaction can be performed multiple times without the loss of the Cu0NPs’ activity. As a proof-of-concept, the hydrogenation of drug molecules “flutamide” and “nimesulide” was also performed and their corresponding amino-compounds were isolated in high selectivity and yield.
- Kinik, F. Pelin,Nguyen, Tu N.,Mensi, Mounir,Ireland, Christopher P.,Stylianou, Kyriakos C.,Smit, Berend
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p. 2833 - 2839
(2020/04/20)
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- Synthesis and characterization of a novel TEMPO?FeNi3/DFNS-laccase magnetic nanocomposite for the reduction of nitro compounds
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Water is an essential substance for life on earth and for all living things. Plants and animals need almost pure water to live; if it is contaminated with harmful chemicals and micro organisms, it will be impossible for them to survive. This study has tried to investigate the performance of catalyst to reduce nitro-aromatic combinations in the attendance of NaBH4 solution duo to the hydrogen source. TEMPO?FeNi3/DFNS-laccase MNPs was prepared, and its features were reviewed using SEM, TEM, XRD, TGA, VSM, AFM, and FTIR. Then, its strength as a nanocatalyst for removal of nitro-aromatic combinations was tested in contact time, initial concentration, the effects of pH and nanocatalyst amount was study. The results of this research proved that TEMPO?FeNi3/DFNS-laccase MNPs has a good return in removal of nitro-aromatic combinations, as its easy synthesis and reliable recovery.
- Mehrzad, Jamshid,Motavalizadehkakhky, Alireza,Saberi, Shima,Zhiani, Rahele
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p. 27297 - 27304
(2020/09/01)
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- Enhanced reduction of nitrobenzene derivatives: Effective strategy executed by Fe3O4/PVA-10%Ag as a versatile hybrid nanocatalyst
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Herein, we present an organic–inorganic hybrid nanocomposite constructed of polyvinyl alcohol (PVA), iron oxide (Fe3O4), and 10% of silver nanoparticles (Ag NPs). First, a convenient in situ method is introduced for the preparation of this efficient catalytic system (Fe3O4/PVA-10%Ag). Further, we study the high catalytic performance for the reduction of nitrobenzene (NB) derivatives as a hazardous species of chemicals and the significant biological activity (antibacterial effects) of the nanocomposite. However, high reaction yields (99%) have been obtained in short reaction times (~15 min). A plausible mechanism is suggested, and all the required characterizations of the presented nanocatalyst are investigated in this study.
- Rahimi, Jamal,Taheri-Ledari, Reza,Niksefat, Maryam,Maleki, Ali
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- Ultrasonic promoted synthesis of Ag nanoparticle decorated thiourea-functionalized magnetic hydroxyapatite: A robust inorganic-organic hybrid nanocatalyst for oxidation and reduction reactions
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In this research, ultrasonic synthesis is applied for the fabrication of a novel catalyst, based on immobilization of silver nanoparticles (AgNPs) on thiourea functionalized magnetic hydroxyapatite. A recoverable Ag nano-catalyst is constructed by decoration of AgNPs on the surface of thiourea modified magnetic hydroxyapatite. Magnetic hydroxyapatite is used as an organic-inorganic hybrid support for the catalyst. The organic-inorganic hybrid support is prepared by co-precipitation, followed by its surface modification through covalent functionalization of 1-(3,5-bis(trifluoromethyl)phenyl)-3-propyl)thiourea. The fabricated catalyst has been characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), powder X-ray diffraction (XRD), nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and Brunauer-Emmett-Teller (BET) analysis. The nanoparticles are mostly tubular in shape and their particle sizes are smaller than 100 nm. This nanocatalyst shows efficient and robust catalytic activity in different reactions, including selective reduction of 4-nitrophenol (4NP) and oxidation of primary amines by applying NaBH4and urea hydrogen peroxide (UHP) as reagents, respectively. The catalyst shows good reusability in 10 sequential reaction runs.
- Bahadorikhalili, Saeed,Arshadi, Hosein,Afrouzandeh, Zahra,Ma'mani, Leila
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p. 8840 - 8848
(2020/06/08)
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- Ultrasound-assisted diversion of nitrobenzene derivatives to their aniline equivalents through a heterogeneous magnetic Ag/Fe3O4-IT nanocomposite catalyst
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A heterogeneous magnetic catalytic system is fabricated and suitably applied for the fast and direct conversion of nitrobenzene (NB) derivatives to their aniline forms. For this purpose, different conditions and methods have been checked with numerous catalytic amounts of the nanocatalyst composite, which was constructed of iron oxide and silver nanoparticles and possessed an isothiazolone organic structure. Herein, the mechanistic aspect of the catalytic functioning of this highly efficient nanocatalyst is highlighted and discussed. Firstly, a convenient preparation route assisted by ultrasonication for this metal and metal oxide nanocomposite is presented. Further, a fast and direct reduction strategy for NBs is investigated using ultrasound irradiation (50 kHz, 200 W L-1). As two great advantages of this catalyst, high magnetic property and excellent reusability are also mentioned. This report well reveals that a really convenient conversion of NBs to anilines can be achieved with a high yield during the rapid reaction time in presence of mild reaction conditions. This journal is
- Taheri-Ledari, Reza,Rahimi, Jamal,Maleki, Ali,Shalan, Ahmed Esmail
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p. 19827 - 19835
(2020/12/04)
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- Cost-effective bio-derived mesoporous carbon nanoparticles-supported palladium catalyst for nitroarene reduction and Suzuki–Miyaura coupling by microwave approach
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A new heterogeneous catalyst was synthesized by immobilizing Pd on areca nut kernel-derived carbon nanospheres (CNSs). The CNSs, without any further activation processes, accommodated 3% of Pd on their surface. The new Pd/CNS material was used for the reduction of nitroarenes and Suzuki–Miyaura coupling of bromoarenes with aryl boronic acids. The reactions were conducted under microwave irradiation at 160 °C using 12 mol% of Pd/CNS (0.36% actual Pd content). The reduction of nitroarenes into their respective amino compounds was achieved in 10–20 min (conversion up to 100%); by contrast, the Suzuki–Miyaura reactions yielded up to 98% at 150 °C with 10 mol% of Pd/CNS catalyst. The products were identified using gas chromatography and nuclear magnetic resonance spectroscopy. The catalyst was isolated from reaction mixture and reused without any significant loss in the activity. Thus, the present work introduces one-pot-derived porous CNSs as efficient catalytic support to Pd, establishing an alternative to existing Pd/C in terms of cost and efficiency.
- Supriya,Ananthnag, Guddekoppa S.,Shetti, Vijayendra S.,Nagaraja,Hegde, Gurumurthy
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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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- Convenient conversion of hazardous nitrobenzene derivatives to aniline analogues by Ag nanoparticles, stabilized on a naturally magnetic pumice/chitosan substrate
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Herein, silver nanoparticles (Ag NPs), as an effective catalyst for the reduction process of nitrobenzene derivatives to non-hazardous and useful aniline derivatives, are conveniently synthesized on an inherently magnetic substrate. For this purpose, an efficient combination of volcanic pumice (VP), which is an extremely porous igneous rock, and a chitosan (CTS) polymeric network is prepared and suitably used for the stabilization of the Ag NPs. High magnetic properties of the fabricated Ag@VP/CTS composite, which have been confirmed via vibrating-sample magnetometer (VSM) analysis, are the first and foremost advantage of the introduced catalytic system since it gives us the opportunity to easily separate the particles and perform purification processes. Briefly, higher yields were obtained in the reduction reactions of nitrobenzenes (NBs) under very mild conditions in a short reaction time. Also, along with the natural biocompatible ingredients (VP and CTS) in the structure, excellent recyclability has been observed for the fabricated Ag@VP/CTS catalytic system, which convinces us to do scaling-up and suggests the presented system can be used for industrial applications. This journal is
- Taheri-Ledari, Reza,Mirmohammadi, Seyedeh Shadi,Valadi, Kobra,Maleki, Ali,Shalan, Ahmed Esmail
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p. 43670 - 43681
(2020/12/25)
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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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- N,S co-doped hierarchically porous carbon materials for efficient metal-free catalysis
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Metal-free carbon catalysts with excellent catalytic performance have drawn much research attention recently. Herein, polymer-derived N,S co-doped carbon catalysts (PDNSC-X) with a hierarchically porous structure were facilely prepared by a cost-effective and convenient strategy via carbonization of a N- and S atom-containing polymer precursor and were subsequently used as efficient metal-free catalysts. The catalytic activity of the as-fabricated PDNSC-800 was greater than those of other reported heteroatom-doped carbon catalysts in catalytic reduction of various nitroarenes. The high catalytic activity of PDNSC-800 was related to the synergistic effects of a high surface area, a hierarchically porous structure, abundant N- and S-containing active sites, and defect formation. In addition, the close relationship between the N species (especially pyrrolic N) and high selectivity in metal-free catalytic synthesis was investigated in the reduction of nitroarenes and selective oxidation of ethylbenzene. This study may provide a new strategy to fabricate specific heteroatom-doped metal-free carbon catalysts for environmentally friendly efficient organic transformation.
- Hu, Xiwei,Sun, Xun,Song, Qiang,Zhu, Yangyang,Long, Yu,Dong, Zhengping
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p. 742 - 752
(2020/02/21)
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- Preparation method of phenylenediamine and phenylenediamine inorganic salt
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The invention discloses a preparation method of phenylenediamine and phenylenediamine inorganic salt. The preparation method of the phenylenediamine comprises the following steps: (1) reacting phthalate with hydroxylamine to obtain dibenzoyl hydroxamic acid or dibenzoyl hydroxamate; and (2) carrying out a rearrangement reaction on the dibenzoyl hydroxamic acid or the dibenzoyl hydroxamate to obtain the phenylenediamine. According to the method, phthalate is used as a starting raw material, nitration and reduction reactions are not used, and hidden dangers of waste acid pollution and polynitrobenzene explosion are eliminated.
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Paragraph 0062; 0063
(2020/10/21)
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- Method for preparing aromatic amine by one-pot method of aromatic ketone
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The invention discloses a method for preparing aromatic amine by an aromatic ketone one-pot method. The method comprises the following steps: uniformly mixing a protonic acid catalyst with aromatic ketone, wherein the molar ratio of the protonic acid catalyst to aromatic ketone is (0.5-8):1; adding hydroxylamine hydrochloride into the obtained mixed solution, wherein the molar ratio of hydroxylamine hydrochloride to a carbonyl group of aromatic ketone is (1-2):1; raising the temperature under a stirring condition to 60-140 DEG C for a reaction; adding hydrochloric acid after finish of the reaction to hydrolyze a generated amide group into an amino; and performing cooling and crystallization to obtain aromatic amine. Polyphosphoric acid, concentrated sulfuric acid and methanesulfonic acid are adopted for catalysis to prepare aromatic amine in one step. Compared with a conventional method, the method provided by the invention has the advantages that reaction steps are reduced, the technological process is greatly simplified, the period is shortened, the cost is lowered, and the efficiency and the productivity are remarkably improved.
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Paragraph 0022-0041; 0048-0059; 0066-0083
(2020/06/02)
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- A polyamine dendritic polymer-copper complex: A reusable catalyst for the additive-free amination of aryl bromides, and iodides
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A porphyrin-initiated amine-functionalized polyepichlorohydrin dendritic polymer (PPECH-Amine) was effectively synthesized, and its water-soluble copper complex (PPECH-Amine-Cu) was developed by treating it with copper acetate. PPECH-Amine and PPECH-Amine-Cu were characterised by different spectroscopic and microscopic techniques. PPECH-Amine-Cu was identified as a reusable catalyst for the amination of bromo- and iodo-benzene derivatives in aqueous media. Due to the presence of residual amino groups in the PPECH-Amine-Cu catalyst, the protocol does not need any additional base additive, as ammonia itself acts as a base and a coupling partner. Due to the good water-soluble nature of this catalyst, it can be easily separated and reused up to six reaction cycles without any loss in its activity.
- Avudaiappan,Palmurukan,Unnikrishnan,Sreekumar
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p. 1477 - 1484
(2020/02/05)
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- Preparation of m-phenylenediamine by using Huffman rearrangement method
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The invention relates to the field of organic functional new material chemicals, and discloses a new process technology for preparing m-phenylenediamine from isophthalamide or a precursor compound thereof through a Huffman rearrangement method for the first time. The m-phenylenediamine is bulk key fine chemicals which are widely used in the related fields such as known dyes and pigments, medical pesticides, building auxiliary materials and the like, and the production process innovation technology of the m-phenylenediamine is widely concerned.
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Paragraph 0038; 0054-0056; 0057-0072
(2020/08/02)
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