58758-09-1Relevant articles and documents
Additive- and Oxidant-Free Expedient Synthesis of Benzimidazoles Catalyzed by Cobalt Nanocomposites on N-Doped Carbon
Wang, Zhaozhan,Song, Tao,Yang, Yong
supporting information, p. 319 - 324 (2019/02/12)
A one-pot direct synthesis of a wide range of biologically active benzimidazoles through coupling of phenylenediamines and aldehydes catalyzed by a highly recyclable nonnoble cobalt nanocomposite was developed. A broad set of benzimidazoles can be efficiently synthesized in high yields and with good functional-group tolerance under additive- and oxidant-free mild conditions. The catalyst can be easily recycled for successive uses, and the process permits gram-scale syntheses of benzimidazoles.
Sulfonated carbon-encapsulated iron nanoparticles as an efficient magnetic nanocatalyst for highly selective synthesis of benzimidazoles
Kasprzak, Artur,Bystrzejewski, Micha?,Poplawska, Magdalena
, p. 6314 - 6322 (2018/05/23)
Surface functionalized carbon-encapsulated iron nanoparticles (CEINs) were found to be a magnetic nanocatalyst for the efficient and highly selective synthesis of benzimidazoles. CEINs were covalently decorated with carboxyl or sulfonyl groups and their catalytic activity was examined. Carboxyl-modified CEINs were obtained via the radical or oxidative treatment, whilst the sulfonated CEINs were obtained using the one-step diazotization approach with sulfanilic acid and isoamyl nitrite. The content of surface acidic groups varied between the obtained materials and was found to be the highest for sulfonyl-modified CEINs. CEINs functionalized with sulfonyl groups were the most efficient and the most selective nanocatalyst for the synthesis of benzimidazoles. Various benzimidazoles were obtained in very high yields (92.5-97.0%). Both metallocene, aliphatic, heterocyclic and aromatic aldehydes substituted with different functional groups were subjected to the synthesis process. The reaction proceeded in a short time, which varied from 25 min to 65 min depending on the aldehyde used. Additionally, the mechanism of the studied catalytic condensation by applying sulfonated CEINs as the catalyst was discussed. Importantly, the developed magnetic nanocatalysts could be easily separated from the reaction mixture using a permanent magnet. The nanocatalysts can be used up to six reaction cycles without any significant loss of their catalytic activity. This work opens up new ways for very efficient and simple synthesis of benzimidazoles-an important class of organic compounds for various biomedical applications.
Concentrated solar radiation promoted unconventional greener approach: Solvent-free benign synthesis of functionalized benzimidazoles
Harsh, Simran,Yusuf, Mohamad,Sharma, Rohit,Kumar, Yogesh,Kumar, Rupesh
, p. 119 - 130 (2018/10/26)
Renewable concentrated solar-radiation (CSR) offered a promising en route for the development of practical, highly efficient, scalable, catalyst free and solvent-free clean process leading to the synthesis of functionalized benzimidazoles. Developed protocol has a very good substrate scope, involves mild reaction conditions and products obtained in good to excellent yields. Method presented the observations in which light alone could affect the remarkable changes with more than 85% energy saving and 75% less reaction time in listed organic transformations.
