1019-85-8Relevant academic research and scientific papers
Preparation, characterization, and application of 1,1′-disulfo-[2,2′-bipyridine]-1,1′-diium chloride ionic liquid as an efficient catalyst for the synthesis of benzimidazole derivatives
Shirini, Farhad,Abedini, Masoumeh,Seddighi, Mohadeseh,Arbosara, Fatemeh Shaabani
, p. 7683 - 7693 (2015)
In this study, 2,2′-bipyridine was treated with chlorosulfonic acid and 1,1′-disulfo-[2,2′-bipyridine]-1,1′-diium chloride, [BiPy](SO3H)2Cl2, as a new ionic liquid catalyst was obtained and characterized with a variety of techniques including IR, 1H, and 13C NMR, Hammett acidity function as well as mass spectra method. After preparation and characterization, this ionic liquid was used as an efficient catalyst for the green and mild synthesis of benzimidazole derivatives. In addition, this reagent is efficiently able to catalyze the preparation of benzimidazole derivatives from the protected derivatives of aldehydes including oximes and semicarbazones. All reactions are performed under mild conditions in excellent yields.
[C12mim] Br: A temperature-dependent phase transfer catalyst and its application for aerobic oxidative synthesis of 2-aryl benzimidazoles, benzoxazoles or benzothiozoles catalyzed by TEMPO based ionic liquid
Yu, Jiatao,Lu, Ming
, p. 578 - 582 (2014)
The application of [C12mim]Br ionic liquid/o-xylene temperature-dependent biphasic system into the [Imim-TEMPO][Cl]/O 2-promoted condensation between o-phenylenediamines, o-aminophenol or o-aminothiophenol with aldehydes for preparing benzimidazoles, benzoxazoles or benzothiozoles is described. Several aldehydes and o-phenylenediamines, o-aminophenol or o-aminothiophenol were reacted efficiently to form corresponding products in excellent yields. Both the [Imim-TEMPO][Cl] and [C12mim]Br could be reused at least eight times without significantly decreasing the catalytic activity. The application of [C12mim]Br ionic liquid/o-xylene temperature-dependent biphasic system into the [Imim-TEMPO][Cl]/O2-promoted condensation between o-phenylenediamines, o-aminophenol or o-aminothiophenol with aldehydes for preparing benzimidazoles, benzoxazoles or benzothiozoles is described. Several aldehydes and o-phenylenediamines, o-aminophenol or o-aminothiophenol were reacted efficiently to form corresponding products in excellent yields. Both the [Imim-TEMPO][Cl] and [C12mim]Br could be reused at least eight times without significantly decreasing the catalytic activity.
VO(acac)2 catalyzed condensation of o-phenylenediamine with aromatic carboxylic acids/aldehydes under microwave radiation affording benzimidazoles
Dey, Madhudeepa,Deb, Krishnajyoti,Dhar, Siddhartha Sankar
, p. 296 - 299 (2011)
Vanadyl acetylacetonate, VO(acac)2, has been found to be very effective catalyst for synthesis of a variety of benzimidazoles under solvent-free condition. The methodology involves the exposure of a mixture of o-phenylenediamine and a selected aromatic carboxylic acid/aldehyde to microwave radiation without the use of any solvent or supporting agents. The benzimidazoles were obtained in quick time with high yields.
Experimental and theoretical approving of anomeric based oxidation in the preparation of 2-sbstituted benz-(imida, oxa and othia)-zoles using [2,6-DMPy-NO2]C(NO2)3 as a novel nano molten salt catalyst
Zolfigol, Mohammad Ali,Khazaei, Ardeshir,Alaie, Saied,Baghery, Saeed,Maleki, Farahnaz,Bayat, Yadollah,Asgari, Asiye
, p. 58667 - 58679 (2016)
The synthesis of 2-sbstituted benz-(imida, oxa and othia)-zole derivatives were occurred in the presence of 2,6-dimethyl-1-nitropyridin-1-ium trinitromethanide [2,6-DMPy-NO2]C(NO2)3via the condensation reaction between 1,2-phenylenediamine or 2-aminophenol or 2-aminothiophenol and corresponding aldehyde at room temperature under solvent-free conditions respectively. [2,6-DMPy-NO2]C(NO2)3 as a nano molten salt (NMS) catalyst was fully characterized by Fourier transform infrared (FT-IR), nuclear magnetic resonance (1H NMR and 13C NMR), mass, thermal gravimetric (TG), derivative thermal gravimetric (DTG), X-ray diffraction patterns (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis. The described reactions are in close agreement with the green chemistry disciplines and their major advantages are good yields, short reaction time and ease of separation. Our recently new introduced concept entitled "anomeric based oxidation" was proposed for the final step of the described synthesis and it was also approved using theoretical studies.
UV-visible light-induced photochemical synthesis of benzimidazoles by coomassie brilliant blue coated on W-ZnO@NH2nanoparticles
Chen, Ruijuan,Jalili, Zahra,Tayebee, Reza
, p. 16359 - 16375 (2021)
Heterogeneous photocatalysts proffer a promising method to actualize eco-friendly and green organic transformations. Herein, a new photochemical-based methodology is disclosed in the preparation of a wide range of benzimidazoles through condensation of o-phenylenediamine with benzyl alcohols in the air under the illumination of an HP mercury lamp in the absence of any oxidizing species catalyzed by a new photocatalyst W-ZnO@NH2-CBB. In this photocatalyst, coomassie brilliant blue (CBB) is heterogenized onto W-ZnO@NH2 to improve the surface characteristics at the molecular level and enhance the photocatalytic activity of both W-ZnO@NH2 and CBB fragments. This unprecedented heterogeneous nanocatalyst is also identified by means of XRD, FT-IR, EDS, TGA-DTG, and SEM. The impact of some influencing parameters on the synthesis route and effects on the catalytic efficacy of W-ZnO@NH2-CBB are also assessed. The appropriate products are attained for both the electron-withdrawing and electron-donating substituents in the utilized aromatic alcohols. Furthermore, preparation of benzimidazoles is demonstrated to occur mainly via a radical mechanism, which shows that reactive species such as ·O2-, OH and h+ would be involved in the photocatalytic process. Stability and reusability studies also warrant good reproducibility of the nanophotocatalyst for at least five runs. Eventually, a hot filtration test proved that the nanohybrid photocatalyst is stable in the reaction medium. Using an inexpensive catalyst, UV-vis light energy and air, as a low cost and plentiful oxidant, puts this methodology in the green chemistry domain and energy-saving organic synthesis strategies. Finally, the anticancer activity of W-ZnO nanoparticles is investigated on MCF7 breast cancer cells by MTT assay. This experiment reveals that the mentioned nanoparticles have significant cytotoxicity towards the selected cell line.
Efficient copper-catalyzed synthesis of 2-arylbenzimidazole derivatives by reaction of 1-fluoro-2-nitrobenzene with benzamidine hydrochlorides
Sayahi, Mohammad Hosein,Khoshneviszadeh, Mehdi,Soheilizad, Mehdi,Saghanezhad, Seyyed Jafar,Mahdavi, Mohammad
, (2018)
[Figure not available: see fulltext.] A novel and efficient approach to the preparation of 2-arylbenzimidazoles is described. Heating a mixture of 1-fluoro-2-nitrobenzene and benzamidine hydrochlorides in the presence of CuBr and K2CO3/su
One-pot synthesis of benzoazoles via dehydrogenative coupling of aromatic 1,2-diamines/2-aminothiophenol and alcohols using Pd/Cu-MOF as a recyclable heterogeneous catalyst
Mokhtari, Javad,Hasani Bozcheloei, Abolfazl
, p. 726 - 731 (2018)
In this paper we report an efficient synthetic approach for the preparation of the widespread numbers of benzoazoles via dehydrogenative coupling of 1,2-phenylenediamine or 2-aminothiophenol and benzyl alcohols by Pd/Cu2(BDC)2(DABCO)-MOF as new heterogeneous catalyst under solvent-free condition. The catalyst recycled and reused for four times without loss of catalytic activity. The structures of benzoazoles were corroborated spectroscopically (1H- and 13C NMR, and elemental analysis) and were confirmed by comparison with reference compounds. A plausible mechanism for this type of reaction is proposed.
Synergic effect of copper-based metal-organic frameworks for highly efficient C-H activation of amidines
Xu, Fen,Kang, Wei-Fen,Wang, Xiao-Ning,Kou, Hao-Dong,Jin, Zhen,Liu, Chun-Sen
, p. 51658 - 51662 (2017)
A Cu-MOF-catalyzed C-H functionalization of substituted amidines was developed for the facile and efficient synthesis of benzimidazoles. More importantly, this transformation is compatible with various substrates derived from aryl nitriles without ortho substituents. Under reaction conditions devoid of O2 atmosphere or specific groups, 537-MOF has been revealed as a key parameter for expanding the reaction scope and increasing the yield up to 96%. Importantly, this strategy also provides numerous opportunities for further utilization of MOFs as catalysts for challenging organic reactions.
Microwave irradiation synthesis of 2-substituted benzimidazoles using PPA as a catalyst under solvent-free conditions
Lu, Jun,Yang, Bingqin,Bai, Yinjuan
, p. 3703 - 3709 (2002)
An efficient microwave irradiation synthesis of 2-substituted benzimidazoles using polyphosphoric acid (PPA) as a catalyst from organic acid and o-phenylenediamine under solvent-free conditions is described. This method is a good option to obtain the title compounds in a simple and an inexpensive way.
Cu–S-(propyl)-2-aminobenzothioate on magnetic nanoparticles: highly efficient and reusable catalyst for synthesis of polyhydroquinoline derivatives and oxidation of sulfides
Ghorbani-Choghamarani, Arash,Tahmasbi, Bahman,Moradi, Parisa,Havasi, Nasrin
, p. 619 - 625 (2016)
Cu–S-(propyl)-2-aminobenzothioate supported on functionalized Fe3O4 magnetic nanoparticles is reported as a reusable and highly efficient nanocatalyst for the one-pot synthesis of polyhydroquinoline derivatives and also for selective
