716-79-0Relevant articles and documents
Effect of phosphorus-modification of titania supports on the iridium-catalyzed synthesis of benzimidazoles
Yu, Han,Wada, Kenji,Fukutake, Tatsuhiro,Feng, Qi,Uemura, Shinobu,Isoda, Kyosuke,Hirai, Tomomi,Iwamoto, Shinji
, p. 410 - 417 (2021)
Modification of titania supports for iridium catalysts by phosphorus species greatly enhanced the activity for the synthesis of benzimidazoles via hydrogen transfer. Two series of phosphorus-modified titanias were used: The iridium catalysts supported on phosphorus-doped rutile titania prepared by the hydrothermal method showed nearly 5 times higher activity for the reaction of 2-nitroaniline (1a) and benzyl alcohol (2a) to 2-phenylbenzimidazole (3aa) than the catalysts supported on unmodified rutile. XPS depth profile study substantiated that the dopant was present mainly on the surface of the rutile support. Therefore, a facile wet impregnation method was applied to modify the surface of anatase titania with phosphoric acid. The use of thus-modified titania enhanced the activity of the iridium catalysts by more than 2.7 times. The FTIR and XPS studies revealed the presence of bidentate phosphorus species on the surface of titania, and the H2-TPR study indicated that phosphorus-modification promoted the formation of iridium species reduced at higher temperature, which would be suitable for the present catalysis.
A novel photoaddition of 2-phenylbenzimidazole
Jones, Richard H.,Ramsden, Christopher A.,Rose, Helen L.
, p. 1031 - 1034 (1996)
Irradiation of 2-phenylbenzimidazole (3) in the presence of methyl acrylate (20 equivalents) using a medium pressure mercury lamp gives methyl 2-(2-phenylbenzimidazol-1-yl)propionate (4) (75%) whose structure has been confirmed by an X-ray analysis. A similar reaction using acrylonitrile gave only a low yield (1%) of the corresponding propionitrile derivative 5. A mechanism involving photoexcitation of 2-phenylbenzimidazole (3) followed by sequential single electron transfer, proton transfer and radical coupling is proposed to account for the formation of the novel photoadducts 4 and 5.
DNA binding, crystal structure, molecular docking studies and anticancer activity evaluation of a copper(II) complex
Liu, Ya-Xian,Mo, Hui-Wen,Lv, Zhen-Yu,Shen, Fang,Zhang, Chun-Lian,Qi, Yong-Yu,Mao, Zong-Wan,Le, Xue-Yi
, p. 259 - 271 (2018)
A copper complex [Cu(HPBM)(l-Phe)(H2O)]·ClO4(1) (HPBM?=?5-methyl-2-(2′-pyridyl)benzimidazole, l-Phe?=?l-phenylalanine anion) was synthesized and characterized by elemental analysis, IR, ESI–MS, HR–ESI–MS, ESR spectroscopy, and by X-ray single-crystal analysis. The binding constant of the complex with calf thymus DNA (CT-DNA) was determined as 7.38 (±?0.57)?×?104?M?1. Further studies indicated that the complex interacts with CT-DNA through minor groove binding. The in vitro cytotoxic activities of both the free proligand and the complex against Eca-109, HeLa and A549 cancer cells and normal LO2 cells were evaluated by the MTT method. The IC50 values range from 5.7?±?0.1 to 8.3?±?0.6?μM. Free HPBM displays no cytotoxic activity against the selected cancer cells, with IC50 values more than 100?μM. Double staining analysis showed that the complex can induce apoptosis in Eca-109 cells. Comet assays demonstrated that the complex can damage DNA and cause apoptosis. The complex also induces an increase in intracellular reactive oxygen species and a reduction in mitochondrial membrane potential. The complex can also increase the intracellular Ca2+ level and induce release of cytochrome c. The cell cycle arrest was investigated by flow cytometry. The results demonstrate that the complex induces apoptosis in Eca-109 cells through DNA-binding and ROS-mediated mitochondrial dysfunctional pathways.
[Diaquo{bis(p-hydroxybenzoato-κ1O1)}(1-methylimidazole- κ1N1)}copper(II)]: Synthesis, crystal structure, catalytic activity and DFT study
Brahman, Dhiraj,Chhetri, Sailesh,Kamath, Amarjit,McArdle, Patrick,Sinha, Biswajit
, (2021/09/04)
Metal-organic hybrid complexes often exhibit large surface area, pore volume, fascinating structures and potential applications including catalytic applications. Hence a new metal-organic hybrid complex [Diaquo{bis(p-hydroxybenzoato-κ1O1)}(1-methylimidazole- κ1N1)}copper(II)] was synthesized using conventional method. Physico-chemical characterization of the complex was performed with FTIR spectroscopy, single crystal X-ray diffraction, TGA, EPR and FESEM. Single crystal X-ray diffraction study suggests it to be three dimensional with space group P212121 (orthorhombic). The crystal achieves its three-dimensional structure and stability through extensive intermolecular hydrogen bonding. Hirshfeld surface analysis, catalytic activity and DFT study of the complex was also performed. The synthesized complex acts as good catalyst in benzimidazole synthesis with good recyclability as catalyst up to 5th run.
1-Methylimidazolium ionic liquid supported on Ni@zeolite-Y: fabrication and performance as a novel multi-functional nanocatalyst for one-pot synthesis of 2-aminothiazoles and 2-aryl benzimidazoles
Kalhor, Mehdi,Zarnegar, Zohre
, p. 519 - 540 (2021/12/03)
In the present study, 1-methyl-3-(3-trimethoxysilylpropyl)-1H-imidazol-3-ium chloride-supported Ni@zeolite-Y-based nanoporous materials (Ni@zeolite-Im-IL) were synthesized and their structures were confirmed using different characterization techniques such as FT-IR, FE-SEM, EDX, XRD, BET and TGA-DTG analyses. In order to synthesize this multi-functional nano-system, zeolite-NaY was modified first, with exchanged Ni2+ ions and 3-chloropropyltriethoxysilane (CPTES) as a coupling reagent and then functionalized to imidazolium chloride ionic liquid by N-methylimidazole. New multi-functional nano-material of Ni@zeolite-Im-IL demonstrated high activity in the catalytic synthesis of 2-aminothiazoles 3a–l by one-pot reaction of methylcarbonyls, thiourea and iodine at 80?°C in DMSO with good to excellent yields (85–98%). Also, the catalytic synthesis of 2-aryl benzimidazoles, 6a–m was performed by the condensational reaction of o-arylendiamine and aromatic aldehydes in EtOH at room temperature with excellent yields (90–98%). Advantages of this efficient synthetic strategy include higher purity and shorter reaction time, excellent yield, easy isolation of products, the good stability, activity and feasible reusability of the metallic ionic liquid nanocatalyst. These benefits have made this method more compatible with the principles of green chemistry. Graphical abstract: [Figure not available: see fulltext.]
Design, preparation, biological investigations and application of a benzoguanamine-based nickel complex for the synthesis of benzimidazoles
Habibi, Davood,Heydari, Somayyeh,Karamian, Roya,Oliaei, Sajjad,Ranjbar, Nika
, (2022/01/19)
The new magnetic-supported benzoguanamine-based nickel complex was prepared, characterized by various procedures and used as a capable heterogeneous nano-catalyst for the synthesis of diverse 2-phenyl-1H-benzo[d]imidazoles from the reaction o-phenylenedia
Coordination-driven reversible supramolecular assembly formation at biological pH: Trace-level detection of Hg2+ and I? ions in real life samples
Dey, Nilanjan
, (2021/10/26)
Pyridine coupled bisbenzimidazole probe has been developed for colorimetric sensing of heavy metal pollutants in the aqueous medium. Mechanistic investigation indicates that Hg2+ ions (detection limit: 7.5 ppb) bind to the pyridyl nitrogen ends
One-Pot Transformation of Lignin and Lignin Model Compounds into Benzimidazoles
Guo, Tao,He, Jianghua,Liu, Tianwei,Zhang, Yuetao
supporting information, (2022/02/07)
It is a challenging task to simultaneously achieve selective depolymerization and valorization of lignin due to their complex structure and relatively stable bonds. We herein report an efficient depolymerization strategy that employs 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) as oxidant/catalyst to selectively convert different oxidized lignin models to a wide variety of 2-phenylbenzimidazole-based compounds in up to 94 % yields, by reacting with o-phenylenediamines with varied substituents. This method could take full advantage of both Cβ and/or Cγ atom in lignin structure to furnish the desirable products instead of forming byproducts, thus exhibiting high atom economy. Furthermore, this strategy can effectively transform both the oxidized hardwood (birch) and softwood (pine) lignin into the corresponding degradation products in up to 45 wt% and 30 wt%, respectively. Through a “one-pot” process, we have successfully realized the oxidation/depolymerization/valorization of natural birch lignin at the same time and produced the benzimidazole derivatives in up to 67 wt% total yields.
An Unexpected Formation of 2-Arylbenzimidazoles from α,α-Diiodo-α’-acetoxyketones and o-Phenylenediamines
Sadhukhan, Santu,Mondal, Swagata,Baire, Beeraiah
, (2022/03/01)
An unusual reactivity of the α,α-diiodo-α’-acetoxyketones with o-phenylenediamines is reported through the formation of 2-arylbenzimidazoles. A systematic study through a series of fruitful control experiments and isolation of key intermediates unravelled the unprecedented domino mechanism. This process involves a stepwise two-carbon fragmentation pathway through domino and sequential amidation–aziridination–decarbonylation–I2-mediated aminative cyclization–oxidation reactions. This strategy employs no additives like oxidant, metal catalyst, bases, and represents yet another novel reactivity profile of the building blocks α,α-diiodo-α’-acetoxyketones.
Palladium catalysed hydrolysis-free arylation of aliphatic nitriles for the synthesis of 4-arylquinolin-2-one/pyrazolone derivatives
Krishna Reddy, Singarajanahalli Mundarinti,Prasanna Kumari, Subramaniyan,Selva Ganesan, Subramaniapillai
, (2021/08/03)
Palladium catalysed addition of arylboronic acid to the readily available 2-cyano-(N-aryl)-acetamide or ethyl-2-cyanoacetate followed by subsequent reaction transform them into the biologically significant 4-arylquinolin-2-one or pyrazolone derivatives. The reaction conditions are robust enough to prevent the hydrolysis of ester/amide moiety during arylation. In addition, the unactivated nitrile moiety in the acetonitrile also converted to the corresponding acetophenone derivative.
