22440-82-0Relevant academic research and scientific papers
Facile Fabrication of Nickel/Heazlewoodite@Carbon Nanosheets and their Superior Catalytic Performance of 4-Nitrophenol Reduction
Wang, Xinyu,Lu, Jing,Zhao, Yunlong,Wang, Xiaopeng,Lin, Zhang,Liu, Xueming,Wu, Ronglan,Yang, Chao,Su, Xintai
, p. 4143 - 4153 (2018)
A facile molten salt method was utilized for the synthesis of carbon anchored nickel/heazlewoodite nanoparticles (Ni/Ni3S2@C nanosheets) with potassium humate as the carbon and sulfur source and NaCl as template. The morphology, particle size and crystallinity of the products were characterized by various techniques containing TEM, FE-SEM and XRD. Furthermore, the mesoporous Ni/Ni3S2@C own easy accessibility of active sites and high surface area (149.04 m2 g?1). Thus, the as-prepared Ni/Ni3S2@C exhibited prominent performance for catalytic reduction of 4-nitrophenol (4-NP). Catalytic reduction of other nitrophenols (NPs) were also tested which can prove that the catalyst own selectivity on reduction of NPs. For durability, the property of the catalyst does not decrease obviously after five cycles. More significant correlations concerning effect of activation parameters (Ea=37.21 kJ mol?1) on 4-NP reduction were scrutinized and discussed. Hence, we provide a facile method for fabrication of metal/metal sulfide@C which own better dispersity, small dimension and excellent catalytic performance for further studies.
Nitroarene and dye reduction with 2:1 Co/Al layered double hydroxide catalysts – Is gold still necessary?
Leandro, Sónia R.,Marques, Inês J.,Torres, Ruben S.,Fernandes, Tiago A.,Vaz, Pedro D.,Nunes, Carla D.
, (2021)
A 2:1 Co/Al layered double hydroxide (LDH) material was synthesized with Cl– anions intercalated and then anion exchanged with deprotonated methionine. This allowed further immobilization of Au nanoparticles. The catalytic performance of the set of three LDH materials for comparative benchmarking was assessed in the aqueous reduction of nitroaromatic compounds and of rhodamine dyes in the presence of NaBH4. All catalysts were found to be very active for the nitro-to-amine reduction. The same was observed for the dyes, where reduction rhodamine 6G was faster than that of rhodamine B, for all catalysts. While the Au-containing catalyst was apparently the one showing the best catalytic activity the LDH with Cl– was found to follow it closely in terms of catalytic performance. In addition, while the LDH catalyst with Au was prone to deactivation by amine products in recycling experiments, the LDH catalyst with Cl– was almost insensitive to that, which is a large advantage. These results showed that using a catalyst based on first-row metals for efficient processes is possible and addresses current sustainable and environmental concerns.
Scope and Optimization of the Double Knorr Cyclization: Synthesis of Novel Symmetrical and Unsymmetrical Tricyclic 1,8-Diazaanthraquinones
Prior, Allan M.,Sun, Dianqing
, p. 859 - 871 (2018/02/10)
The Knorr cyclization of β-ketoanilides to form 2-quinolones in the presence of acid is well documented chemistry. Double Knorr cyclization is rare, with very few examples appearing in the literature to date. The double Knorr methodology can provide access to tricyclic 1,8-diazaanthraquinones, a scaffold seen in the diazaquinomycin family. The optimized synthesis of diazaquinomycin A and structural analogues thereof via double Knorr cyclization of di-β-ketoanilide precursor substrates is reported. The scope and generality of the double Knorr cyclization were investigated along with an optimization study. The double Knorr cyclization was found to be sensitive to steric bulk on precursor substrates. In addition, the presence of a 5-hydroxy group on the 1,3-di-β-ketoanilide facilitated the double Knorr cyclization, possibly due to its stabilizing effect on the carbocation intermediates formed during the reaction.
Carbon nitride supported palladium nanoparticles: An active system for the reduction of aromatic nitro-compounds
Nandi, Debkumar,Siwal, Samarjeet,Choudhary, Meenakshi,Mallick, Kaushik
, p. 31 - 38 (2016/06/09)
Synthesis of carbon nitride supported highly dispersed ultrafine palladium nanoparticles has been reported for the reduction of aromatic nitro-compounds using hydrazine hydrate as a reducing agent. As a demonstration, the as-synthesized carbon nitride-palladium composite was shown to be a highly active and chemo-selective for the title reaction. Utilizing the optimized reaction conditions a set of aromatic nitro compounds have been converted to their corresponding amine derivatives with good to excellent yield ranging from 80% to 99%. The catalyst can be used for multiple times without affecting the catalytic performance and can also be stored for a long time at ambient condition maintaining the high catalytic efficiency.
Palladium Supported on Graphitic Carbon Nitride: An Efficient and Recyclable Heterogeneous Catalyst for Reduction of Nitroarenes and Suzuki Coupling Reaction
Zhao, Yukai,Tang, Ruiren,Huang, Rong
, p. 1961 - 1971 (2015/12/24)
In this study, a novel platelet-like nanocatalyst, Pd/g-C3N4 with easily approachable active sites, was developed. The mesoporous graphitic carbon nitride (g-C3N4) is a layered structure connected by planar amino groups, which can work as stabilizer and active support for noble metal nanoparticles. The palladium nanoparticles with an average particle size of 3.25 nm were evenly dispersed on the surface of g-C3N4 without aggregation. Detailed charaterizations reveal that there is no covalent-bond interaction between g-C3N4 and Pd NPs. The Pd/g-C3N4 catalyst showed excellent catalytic activity in the reduction of nitroarenes by NaBH4, and Suzuki coupling reaction of aryl halides with arylboronic acids under mild conditions. The reduction of 4-nitrophenol has a pseudo-first-order rate constant of 7.29 × 10-3 s-1, and an activity parameter of 1.37 s-1 mM-1, which is higher than those reported in the literature. Furthermore, the Suzuki coupling reactions processed smoothly with 97.0 % isolate yield in less than 30 min in water with PEG600 as the additive. The catalyst could be recycled for five times without significant loss of catalytic activity, which confirmed the good stability of the catalyst. Graphical Abstract: [Figure not available: see fulltext.]
2-Aminobenzoxazole ligands of the hepatitis C virus internal ribosome entry site
Rynearson, Kevin D.,Charrette, Brian,Gabriel, Christopher,Moreno, Jesus,Boerneke, Mark A.,Dibrov, Sergey M.,Hermann, Thomas
supporting information, p. 3521 - 3525 (2014/07/22)
2-Aminobenzoxazoles have been synthesized as ligands for the hepatitis C virus (HCV) internal ribosome entry site (IRES) RNA. The compounds were designed to explore the less basic benzoxazole system as a replacement for the core scaffold in previously discovered benzimidazole viral translation inhibitors. Structure-activity relationships in the target binding of substituted benzoxazole ligands were investigated.
PYRIMIDINE DERIVATIVES
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Page/Page column 89, (2011/04/14)
The invention concerns benzamide compounds of Formula (I), or a pharmaceutically acceptable salt thereof, where R1, ring A, n, R3, and R4 are as defined in the description. The present invention also relates to processes for the preparation of such compounds, pharmaceutical compositions containing them and their use in the manufacture of a medicament for use as an antiproliferative agent in the prevention or treatment of tumours or other proliferative conditions which are sensitive to the inhibition of EphB4, and/or EphA2 and/or Src kinases.
Identification of a series of benzoxazoles as potent 5-HT6 ligands
Liu, Kevin G.,Lo, Jennifer R.,Comery, Thomas A.,Zhang, Guo Ming,Zhang, Jean Y.,Kowal, Dianne M.,Smith, Deborah L.,Di, Li,Kerns, Edward H.,Schechter, Lee E.,Robichaud, Albert J.
scheme or table, p. 1115 - 1117 (2009/08/07)
As part of our continuing efforts to identify therapeutics for CNS diseases such as schizophrenia and Alzheimer's disease (AD), we have been focused on the 5-HT6 receptor in order to identify potent and selective ligands as a potential treatment for cognitive dysfunction. Herein we report the identification of a novel series of benzoxazole derivatives as potent 5-HT6 ligands. The synthesis and detailed SAR of this class of compounds are reported. The compounds have been shown to be full antagonists in a cyclic AMP functional assay.
Benzoxazole and benzothiazole derivatives as 5-hydroxytryptamine-6 ligands
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Page/Page column 14, (2008/06/13)
The present invention provides a compound of formula I and the use thereof for the treatment of a central nervous system disorder related to or affected by the 5-HT6 receptor.
