53314-16-2Relevant academic research and scientific papers
Selective C-C bonds formation, N-alkylation and benzo[d]imidazoles synthesis by a recyclable zinc composite
Zhu, Guanxin,Duan, Zheng-Chao,Zhu, Haiyan,Ye, Dongdong,Wang, Dawei
supporting information, p. 266 - 270 (2021/08/06)
Earth abundant metals are much less expensive, promising, valuable metals and could be served as catalysts for the borrowing hydrogen reaction, dehydrogenation and heterocycles synthesis, instead of noble metals. The uniformly dispersed zinc composites were designed, synthesized and carefully characterized by means of XPS, EDS, TEM and XRD. The resulting zinc composite showed good catalytic activity for the N-alkylation of amines with amines, ketones with alcohols in water under base-free conditions, while unsaturated carbonyl compounds could also be synthesized by tuning the reaction conditions. Importantly, it was the first time to realize the synthesis of 2-aryl-1H-benzo[d]imidazole derivatives by using this zinc composite under green conditions. Meanwhile, this zinc catalyst could be easily recovered and reused for at least five times.
Water extract of onion catalyst: An economical green route for the synthesis of 2-substituted and 1,2-disubstituted benzimidazole derivatives with high selectivity
Kaliyan, Prabakaran,Selvaraj, Loganathan,Muthu, Seenivasa Perumal
supporting information, p. 340 - 349 (2020/12/01)
An efficient, environmental friendly and substrate controlled method of synthesis of 2-substituted benzimidazole derivatives 3 and 1,2-disubstituted benzimidazole derivatives 4 with high selectivity has been achieved from the reaction of o-phenylenediamine 1 and aldehydes 2 in the presence of water extract of onion and selecting suitable reaction medium. This method is widely applicable for variety of aldehydes such as aromatic/aliphatic/heterocyclic aldehydes and 1,2-diamines to afford 2-substituted benzimidazole derivatives 3 and 1,2-disubstituted benzimidazole derivatives 4 in good to excellent yields (up to 96%). The developed method of water extract of onion catalysis produced 2-substituted benzimidazoles 3 from aromatic aldehydes having electron-withdrawing groups, whereas aromatic aldehydes bearing electron donating groups selectively furnished 1,2-disubstituted benzimidazole 4 derivatives. The process described here has several advantages of cheap, low energy consumption, commercially available starting materials, operational simplicity and nontoxic catalyst. The use of water extract of onion makes this present methodology green and giving a useful contribution to the existing methods available for the preparation of benzimidazole derivatives. In addition, Hammett correlation of substituent constant (σ) vs percentage (%) yield has been established.
A facile and efficient synthesis of benzimidazole as potential anticancer agents
Hoang, Thi-Kim-Dung,Huynh, Thi-Kim-Chi,Nguyen, Thanh-Danh,Nguyen, Thi-Hong-An,Tran, Ngoc-Hoang-Son
, (2020/07/13)
Abstract: This study reports a simple process to synthesize and separate of 2-(substituted-phenyl) benzimidazole derivatives with high yield and efficiency. Specifically, by reacting ortho-phenylenediamines with benzaldehydes using sodium metabisulphite a
Copper-Mediated Diamination of Arylboronic Acids for the Synthesis of 2-Aryl Benzimidazoles Using Trimethylsilyl Azide as the Amino Sources with Aldehydes
Xie, Zeqiang,Zhou, Fengtao,Ding, Ke
supporting information, p. 3442 - 3446 (2020/07/30)
A direct and versatile copper-mediated three-component reaction of arylboronic acids, trimethylsilyl azide and aldehydes for the synthesis of benzimidazoles is reported. The reaction is well tolerated by a wide range of substituted aromatic aldehydes and aromatic boronic acids to produce the corresponding benzimidazoles in moderate to high yields. Mechanism investigations demonstrated that copper-promoted Chan-Evans-Lam coupling, C?H amination, and oxidative cycloaddition are involved in the tandem processes. (Figure presented.).
Synthesis, bioevaluation and docking studies of some 2-phenyl-1H-benzimidazole derivatives as anthelminthic agents against the nematode Teladorsagia circumcincta
Escala, Nerea,Valderas-García, Elora,Bardón, María álvarez,Gómez de Agüero, Verónica Castilla,Escarcena, Ricardo,López-Pérez, José Luis,Rojo-Vázquez, Francisco A.,San Feliciano, Arturo,Bala?a-Fouce, Rafael,Martínez-Valladares, María,Olmo, Esther del
, (2020/10/02)
Gastrointestinal nematode infections are the main diseases in herds of small ruminants. Resistance to the main established drugs has become a worldwide problem. The purpose of this study is to obtain and evaluate the in vitro ovicidal and larvicidal activity of some 2-phenylbenzimidazole derivatives on susceptible and resistant strains of Teladorsagia circumcincta. Compounds were prepared by known procedures from substituted o-phenylenediamines and arylaldehydes or intermediate sodium 1-hydroxyphenylmethanesulfonate derivatives. Egg Hatch Test (EHT), Larval Mortality Test (LMT) and Larval Migration Inhibition Test (LMIT) were used in the initial screening of compounds at 50 μM concentration, and EC50 values were determined for the most potent compounds. Cytotoxicity evaluation of compounds was conducted on human Caco-2 and HepG2 cell lines to calculate their Selectivity Indexes (SI). At 50 μM concentration, nine out of twenty-four compounds displayed more than 98% ovicidal activity on a susceptible strain, and four of them showed more than 86% on one resistant strain. The most potent ovicidal benzimidazole (BZ) 3 showed EC50 = 6.30 μM, for the susceptible strain, while BZ 2 showed the lowest EC50 value of 14.5 μM for the resistant strain. Docking studies of most potent compounds in a modelled Teladorsagia tubulin indicated an inverted orientation for BZ 1 in the colchicine binding site, probably due to its fair interaction with glutamic acid at codon 198, which could justify its inactivity against the resistant strain of T. circumcincta.
Amphiphilic Dendrimer as Reverse Micelle: Synthesis, Characterization and Application as Homogeneous Organocatalyst
Sherly mole,George, Smitha,Shebitha,Kannan,Mathew, Suseela,Asha,Sreekumar
, (2019/10/14)
The core and surface terminal groups are the two main catalytic sites in a dendrimer. In most of the reported examples, the catalytic sites in dendritic catalysis are the surface terminal functional groups. This perspective article concerned with the dend
Air-stable Ruthenium(II)-NNN Pincer Complexes for the Efficient Coupling of Aromatic Diamines and Alcohols to 1H-benzo[d]imidazoles with the Liberation of H2
Li, Lin,Luo, Qi,Cui, Huahua,Li, Renjie,Zhang, Jing,Peng, Tianyou
, p. 1607 - 1613 (2018/02/28)
Two new phosphine-free RuII-NNN pincer complexes ([RuCl(L1)(CH3CN)2]Cl (1) and [RuCl(L2)(CH3CN)2]Cl (2) [L1=2,6-bis(1H-imidazole-2-yl)pyridine, L2=2,6-bis(1-hexyl-1H-imidazole-2-yl)pyridine] were synthesized to catalyze the condensation of benzyl alcohol and benzene-1,2-diamine homogeneously to 2-pheny-1H-benzo[d]imidazole and H2. The reactivity in the order of 1>2 is lower than that of the phosphine-containing RuII-NNN pincer complex [RuCl2(L1)(PPh3)3] (3), and thus a homogeneous system that contained 1, 1 equivalent of 1,2-bis(diphenylphosphanyl)ethane, and 10 equivalents of NaBPh4 was developed to improve the catalytic efficiency for the condensation of primary alcohols and benzene-1,2-diamine (or its derivatives) to 2-substituted 1H-benzo[d]imidazoles in excellent yields (up to 97 %) and turnover numbers (388). This system can be used to realize the facile one-step synthesis of 1H-benzo[d]imidazole derivatives from alcohols without the use of an oxidant and/or a stoichiometric amount of inorganic base that is usually necessary in homogeneous systems reported previously.
Br?nsted acid-catalyzed metal-free one-pot synthesis of benzimidazoles via [4+1] heteroannulation of ortho-phenylenediamines with β-oxodithioesters
Srivastava, Abhijeet,Shukla, Gaurav,Yadav, Dhananjay,Singh, Maya Shankar
, p. 81 - 89 (2018/02/07)
An operationally simple and user-friendly one-pot domino protocol for the synthesis of 2-aryl/hetaryl benzimidazoles has been devised from easily available and inexpensive 1,2-phenylenediamines and β-oxodithioesters. The strategic [4+1] heteroannulation i
Tunable Triazole-Phosphine-Copper Catalysts for the Synthesis of 2-Aryl-1H-benzo[d]imidazoles from Benzyl Alcohols and Diamines by Acceptorless Dehydrogenation and Borrowing Hydrogen Reactions
Xu, Zhaojun,Wang, Duo-Sheng,Yu, Xiaoli,Yang, Yongchun,Wang, Dawei
supporting information, p. 3332 - 3340 (2017/10/06)
Triazole-phosphine-copper complexes (TAP?Cu) have been synthesized and applied as tunable and efficient catalysts for the selective synthesis of fluoro-substituted 2-aryl-1H-benzo[d]imidazole and 1-benzyl-2-aryl-1H-benzo[d]imidazole derivatives from simple alcohols in only one step. TAP?Cu exhibited excellent and tunable catalytic activity for both dehydrogenation and borrowing hydrogen reactions with more than 80 examples being demonstrated for the first time. It was observed that the ligand played a critical role in catalyst activity. Mechanistic studies and deuterium labeling experiments indicated that the reactions proceeded by an initial and reversible alcohol dehydrogenation resulting in a copper hydride intermediate. This was also supported by the direct observation of a diagnostic copper hydride signal by solid-state infrared spectroscopy. The TAP?Cu-H complex showed absorptions at 912 cm?1 that could be assigned to copper?hydride stretches. Furthermore, the direct trapping of an intermediate bisimine was also successfully performed. (Figure presented.).
Synthesis of benzimidazole and quinoxaline derivatives using reusable sulfonated rice husk ash (RHA-SO3H) as a green and efficient solid acid catalyst
Shamsi-Sani, Mahnaz,Shirini, Farhad,Abedini, Masoumeh,Seddighi, Mohadeseh
, p. 1091 - 1099 (2016/04/26)
In this work, a simple, rapid and efficient method for the preparation of benzimidazoles and quinoxalines from the condensation of o-phenylene diamines with aldehydes and/or 1,2-dicarbonyl compounds in the presence of sulfonated rice husk ash (RHA-SO3H) as an efficient green catalyst is reported. RHA-SO3H can be easily prepared using a readily available organic compound by simple modification of rice husk ash. All reactions are performed under mild reaction conditions with high to excellent yields. The method is applicable to aromatic, unsaturated and hetero aromatic aldehydes. The advantages of this method are short reaction times, milder conditions, easy work-up, solvent-free conditions and catalyst reusability.
