159139-79-4Relevant academic research and scientific papers
Highly chemoselective reduction of nitroarenes over non-noble metal nickel-molybdenum oxide catalysts
Huang, Haigen,Wang, Xueguang,Li, Xu,Chen, Chenju,Zou, Xiujing,Ding, Weizhong,Lu, Xionggang
, p. 809 - 815 (2017)
The chemoselective reduction of nitroarenes is an important transformation for the production of arylamines, which are the primary intermediates in the synthesis of pharmaceuticals, agrochemicals and dyes. Heterogeneous non-noble metal nickel-molybdenum oxide catalysts supported on ordered mesoporous silica SBA-15 (Ni-MoO3/CN@SBA-15) were prepared for the first time by treating SBA-15-supported nickel-molybdenum oxide materials with 1,10-phenanthroline, and exhibited unprecedented catalytic activity and chemoselectivity for the reduction of various substituted nitroarenes to the corresponding aromatic amines in ethanol with hydrazine hydrate as a hydrogen donor under mild conditions owing to the synergistic effect of metal Ni and MoO3 species, affording excellent yields of >99% within very short reaction periods (≤60 min). The Ni-MoO3/CN@SBA-15 catalysts were highly stable and could easily be recovered by simple filtration or by an external magnetic field for at least ten recycling reactions without any observable loss of catalytic performance or leaching of metal components.
Mechanism-Based Trapping of the Quinonoid Intermediate by Using the K276R Mutant of PLP-Dependent 3-Aminobenzoate Synthase PctV in the Biosynthesis of Pactamycin
Hirayama, Akane,Miyanaga, Akimasa,Kudo, Fumitaka,Eguchi, Tadashi
, p. 2484 - 2490 (2015)
Mutational analysis of the pyridoxal 5′-phosphate (PLP)-dependent enzyme PctV was carried out to elucidate the multi-step reaction mechanism for the formation of 3-aminobenzoate (3-ABA) from 3-dehydroshikimate (3-DSA). Introduction of mutation K276R led to the accumulation of a quinonoid intermediate with an absorption maximum at 580 nm after the reaction of pyridoxamine 5′-phosphate (PMP) with 3-DSA. The chemical structure of this intermediate was supported by X-ray crystallographic analysis of the complex formed between the K276R mutant and the quinonoid intermediate. These results clearly show that a quinonoid intermediate is involved in the formation of 3-ABA. They also indicate that Lys276 (in the active site of PctV) plays multiple roles, including acid/base catalysis during the dehydration reaction of the quinonoid intermediate.
A facile method for the synthesis of graphene-like 2D metal oxides and their excellent catalytic application in the hydrogenation of nitroarenes
Lei, Lijun,Wu, Zhiwei,Liu, Huan,Qin, Zhangfeng,Chen, Chengmeng,Luo, Li,Wang, Guofu,Fan, Weibin,Wang, Jianguo
, p. 9948 - 9961 (2018)
Graphene-like two-dimensional (2D) metal oxides in the form of nanosheets (NSs) often exhibit superior performance in many applications in comparison with their bulk counterparts, owing to their unique electronic and physicochemical properties arising from their layered 2D structure; however, it is still a great challenge to produce 2D metal oxides in a facile way, especially for non-layered metal oxides. In the present work, a modified evaporation induced self-assembly (EISA) method was developed to synthesize graphene-like CeO2 nanosheets (NS-CeO2). Moreover, the EISA method is proved to be rather universal and a series of other single and mixed metal oxides, including TiO2, ZrO2, CoOx, NiO, Al2O3, CuO, CuO-ZrO2, MnOx-Al2O3, FeOx-CoOx, Cr2O3-ZnO, CeO2-ZrO2, CeO2-CuO, CeO2-CoOx, CeO2-La2O3, CeO2-FeOx, CeO2-MnOx, CeO2-ZnO, CeO2-Al2O3, CeO2-NiO, CeO2-Cr2O3, CeO2-TiO2, MnOx-CeO2-ZrO2, and CuO-CeO2-ZrO2, can be successfully prepared in the form of nanosheets with tunable pore structure and sheet thickness by using this method. The catalytic application of the graphene-like metal oxides was considered and the results illustrate that the CeO2 nanosheets decorated with Pd clusters (Pd/NS-CeO2) exhibit excellent catalytic performance in the hydrogenation of nitroarenes under mild conditions; over them, nitrobenzene can be completely converted to aniline even at room temperature in a short time. A series of characterization results combined with DFT calculations demonstrate that the CeO2 nanosheets are enriched with surface defects and Ce3+ species, which can promote the adsorption and activation of nitroarenes. The present work brings forward a facile and effective approach to synthesize graphene-like metal oxides with superior catalytic performance; besides, the results obtained in this work are also rather helpful to clarify the relationship between the 2D structure and performance of the Pd/NS-CeO2 catalyst in the hydrogenation of nitroarenes.
Active Pd/Fe(OH)x catalyst preparation for nitrobenzene hydrogenation by tracing aqueous phase chlorine concentrations in the washing step of catalyst precursors
Zhang, Chengming,Cui, Xinjiang,Deng, Youquan,Shi, Feng
, p. 6050 - 6054 (2014)
By tracing the chlorine concentrations in the aqueous solutions containing the catalyst precursors, Pd/Fe(OH)x catalysts with different activities can be controllably prepared. For the hydrogenation of nitrobenzene, the active Pd/Fe(OH)x catalysts were obtained from aqueous solutions with chlorine concentrations below 18 ppm and above 8 ppm.
Palladium modified magnetic mesoporous carbon derived from metal-organic frameworks as a highly efficient and recyclable catalyst for hydrogenation of nitroarenes
Dong, Zhengping,Liang, Kun,Dong, Chunxu,Li, Xinlin,Le, Xuanduong,Ma, Jiantai
, p. 20987 - 20991 (2015)
We present a facile route for the fabrication of palladium modified magnetic nanoparticles (Fe@Pd NPs) embedded in mesoporous carbon (MC), derived from metal-organic frameworks, to produce the Fe@Pd-MC nanocatalyst. The Fe@Pd-MC nanocatalyst exhibited excellent catalytic activity toward the hydrogenation of nitroarenes as well as easy recovery and reusability.
Palladium supported on hollow magnetic mesoporous spheres: A recoverable catalyst for hydrogenation and Suzuki reaction
Liu, Hengzhi,Wang, Peng,Yang, Honglei,Niu, Jianrui,Ma, Jiantai
, p. 4343 - 4350 (2015)
A high-performance palladium catalyst was developed by the covalent binding of a Schiff base ligand, N,N′-bis(3-salicylidenaminopropyl)amine (salpr), on the surface of hollow magnetic mesoporous spheres (HMMS) followed by immobilization with Pd(0). The catalyst was characterized by TEM, EDX, FT-IR, XRD, VSM, TGA and N2 adsorption-desorption. The novel catalyst exhibited high activity in hydrogenation and Suzuki coupling reaction. Furthermore, it could be recovered from the reaction mixture in a facile manner and recycled six times without any loss of activity.
Phase and shape dependent photoactivity of titania for nitroaromatics reduction under UV light irradiation
Kaur, Jaspreet,Pal, Bonamali
, p. 803 - 809 (2019)
This work describes importance of TiO2 nanostructures of different shapes (nanospheres and nanorods) and crystal phases (anatase and rutile) for the photoreduction of nitroaromatics into corresponding aminoaromatics under UV light irradiation. Anatase nanoparticles were most active of all the catalysts due to the superior stability of this phase and comparatively the rutile nanorods (L×W = 28-30 nm×3.5-3.8 nm) showed superior photoactivity (～3 times) as compared to rutile nanospheres of size 122 nm for the photoreduction due to electron transport along longitudinal length, larger surface area (69 m2g-1), quenched PL emission, increased lifetime of charge carriers (1.8 ns) of rutile nanorods as compare to rutile nanospheres having lower surface area (18 m2g-1) and charge carrier lifetime (1.1 ns). The overall rate of reduction/hour for m-NBA and m-NT photoreduction with all of these catalysts has been found to vary in the following order ANP > P25-TiO2 > RNR > ANR > RNP.
Copper nanoparticles (CuNPs) catalyzed chemoselective reduction of nitroarenes in aqueous medium
Chand, Dillip Kumar,Rai, Randhir
, (2021/08/20)
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.]
Selective reduction of nitro-compounds to primary amines by tetrapyridinoporphyrazinato zinc (II) supported on DFNS
Hosseiny, Malihesadat,Khosroyar, Susan,Kiani, Zahra,Motavalizadehkakhky, Alireza,Zhiani, Rahele
, (2021/06/14)
Here, we created and synthesized a heterogeneous catalyst from porphyrazinatozinc (tmtppa-Zn) supported on DFNS (tmtppa-Zn/DFNS). This is a simple method for hydrogenation of nitro-compounds and their conversion to primary amines without producing toxic by-products. These reactions take place under mild reaction situations. The catalyst system was comfortably retrieved and reutilized in at least ten runs without the reduction of catalytic activity.
Cobalt oxide NPs immobilized on environmentally benign biological macromolecule-derived N-doped mesoporous carbon as an efficient catalyst for hydrogenation of nitroarenes
Elhampour, Ali,Nanadegani, Zahra Soleimani,Nemati, Firouzeh,Rangraz, Yalda
, (2020/09/15)
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.
