1024287-07-7Relevant academic research and scientific papers
1,2-Disubstituted Benzimidazoles by the Iron Catalyzed Cross-Dehydrogenative Coupling of Isomeric o-Phenylenediamine Substrates
Foss, Frank W.,Palacios, Philip M.,Pierce, Brad S.,Thapa, Pawan,Tran, Tam
, p. 1991 - 2009 (2020/03/13)
Benzimidazoles are common in nature, medicines, and materials. Numerous strategies for preparing 2-arylbenzimidazoles exist. In this work, 1,2-disubstituted benzimidazoles were prepared from various mono- and disubstituted ortho-phenylenediamines (OPD) by iron-catalyzed oxidative coupling. Specifically, O2 and FeCl3·6H2O catalyzed the cross-dehydrogenative coupling and aromatization of diarylmethyl and dialkyl benzimidazole precursors. N,N′-Disubstituted-OPD substrates were significantly more reactive than their N,N-disubstituted isomers, which appears to be relative to their propensity for complexation and charge transfer with Fe3+. The reaction also converted N-monosubstituted OPD substrates to 2-substituted benzimidazoles; however, electron-poor substrates produce 1,2-disubstituted benzimidazoles by intermolecular imino-transfer. Kinetic, reagent, and spectroscopic (UV-vis and EPR) studies suggest a mechanism involving metal-substrate complexation, charge transfer, and aerobic turnover, involving high-valent Fe(IV) intermediates. Overall, comparative strategies for the relatively sustainable and efficient synthesis of 1,2-disubstituted benzimidazoles are demonstrated.
A one-pot synthesis of benzimidazoles via aerobic oxidative condensation of benzyl alcohols with o-phenylenediamines catalyzed by [MIMPs]+Cl-/NaNO2/TEMPO
Geng, Zhenzhen,Zhang, Hong-Yu,Yin, Guohui,Zhang, Yuecheng,Zhao, Jiquan
, p. 557 - 565 (2020/03/30)
The ionic liquid 1-methyl-3-(3-sulfopropyl)imidazolium chloride ([MIMPs]+Cl-) in combination with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and sodium nitrite (NaNO2) as a catalytic system demonstrates high efficiency in the one-pot two-step aerobic oxidative condensation of benzyl alcohols with 1,2-phenylenediamines to give benzimidazoles. Various benzimidazoles are obtained in good to excellent yields by this strategy.
An efficient route for the synthesis of benzimidazoles via a hydrogen-transfer strategy between o-nitroanilines and alcohols
Li, Xiaotong,Hu, Renhe,Tong, Yao,Pan, Qiang,Miao, Dazhuang,Han, Shiqing
supporting information, p. 4645 - 4649 (2016/09/23)
[1,1′-Bis(diphenylphosphino)ferrocene]dichloropalladium(II) has been used as an efficient catalyst for the synthesis of 2-substituted benzimidazoles via a hydrogen-transfer strategy. Various 2-substituted benzimidazoles were synthesized in good to excellent yields (up to 97%). The reaction shows good functional group tolerance. And no additional additive, oxidant, or reductant was required for the reaction.
Metal-free TEMPO-promoted C(sp3)-H amination to afford multisubstituted benzimidazoles
Xue, Ding,Long, Ya-Qiu
, p. 4727 - 4734 (2014/06/09)
An efficient TEMPO-air/cat. TEMPO-O2 oxidative protocol was developed to synthesize multisubstituted or fused tetracyclic benzimidazoles via a metal-free oxidative C-N coupling between the sp3 C-H and free N-H of readily available N1-benzyl/alkyl-1,2-phenylenediamines.
Synthesis and potent antifungal activity against Candida species of some novel 1H-benzimidazoles
Goeker, Hakan,Alp, Mehmet,Ates-Alagoez, Zeynep,Yildiz, Sulhiye
experimental part, p. 936 - 948 (2009/12/05)
(Chemical Equation Presented) A series of 47 novel N1-alkylated- 2-aryl-5(6)-substituted-1H-benzimidazoles and their three novel indole analogues were synthesized and evaluated for in vitro antifungal activities against Candida species by the tube dilution method. The results showed that compounds 79 and 80, having pyridine at the position C-2, of benzimidazoles exhibited the greatest activity with MIC values of 6.25-3.12 μg/mL. Indole analogues 108-110 have no inhibitory activity.
