10394-40-8Relevant academic research and scientific papers
Cu-Catalyzed C-H Allylation of Benzimidazoles with Allenes
Dong, Yaxi,Breit, Bernhard
, p. 6765 - 6769 (2021/09/11)
CuH-catalyzed intramolecular cyclization and intermolecular allylation of benzimidazoles with allenes have been described. The reaction proceeded smoothly with the catalytic system of Cu(OAc)2/Xantphos and catalytic amount of (MeO)2MeSiH. This protocol features mild reaction conditions and a good tolerance of substrates bearing electron-withdrawing, electron-donating, or electron-neutral groups. A new catalytic mechanism was proposed for this copper hydride catalytic system.
Efficient N-Heterocyclic Carbene/Ruthenium Catalytic Systems for the Alcohol Amidation with Amines: Involvement of Poly-Carbene Complexes?
Cheng, Hua,Xiong, Mao-Qian,Zhang, Ni,Wang, Hua-Jing,Miao, Yang,Su, Wei,Yuan, Ye,Chen, Cheng,Verpoort, Francis
, p. 4338 - 4345 (2018/09/06)
The atom-economic direct amidation of alcohols with amines has been recently highlighted as an attractive and promising transformation. Among the versatile reported catalytic systems, in situ generated N-heterocyclic carbene (NHC)/ruthenium (Ru) catalytic systems have demonstrated their advantages such as easy operation and use of commercial Ru compounds. However, the existing catalyst loadings are relatively high, and additional insights for the in situ catalyst generation are still not well-documented. In this work, a variety of benzimidazole-based NHC precursors were initially synthesized. Through the screening of various NHC precursors and other reaction conditions, active in situ catalytic systems were discovered for the efficient amide synthesis. Notably, the catalyst loading is as low as 0.5 mol %. Furthermore, additional experiments were performed to validate the rationale for the superiority of the current catalytic systems over our previous system. It was observed that the ligand structure is one of the reasons for the higher activity. In addition, the higher ratio of the NHC precursor/[Ru] is another important factor for the improvement. Further HR-MS analysis identified the formation of two mono-NHC-Ru species as major species and two Ru species bearing multiple NHC ligands as minor species. Hopefully, the efficient and readily-accessible catalytic systems reported herein could demonstrate great potential for further practical applications.
BENZIMIDAZOLE DERIVATIVES AND USES THEREOF
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Paragraph 0307; 0394, (2015/12/31)
Benzimidazole derivatives of Formula I, that modulate the activity of ACSS2 are disclosed for therapeutic use. The fused imidazole ring of the compounds disclosed has a diarylmethyl or diarylmethanol moiety attached at the 2-position and the compounds have at least one other substituent at the 5 or 6 position of the benzimidazole. Also disclosed are methods of using the benzimidazole compounds for the treatment of diseases or disorders, such as cancer.
Supercritical methanol as solvent and carbon source in the catalytic conversion of 1,2-diaminobenzenes and 2-nitroanilines to benzimidazoles
Sun, Zhuohua,Bottari, Giovanni,Barta, Katalin
, p. 5172 - 5181 (2015/12/08)
Benzimidazoles and N-methylbenzimidazoles were synthesized by simply heating 1,2-diaminobenzenes in supercritical methanol over copper-doped porous metal oxides. These catalysts were derived from synthetic hydrotalcites that only contain earth-abundant starting materials. The carbon equivalents needed for the construction of the benzimidazole core originated from the solvent itself, which is known to undergo reforming to hydrogen and carbon monoxide through the formation of a formaldehyde intermediate. A variety of 1,2-diaminobenzenes were converted to the corresponding mixtures of benzimidazoles and N-methylated analogues in good yields. Interestingly, the more challenging, but readily available 2-nitroanilines, which require an additional reduction step prior to cyclization, could also be successfully converted to benzimidazoles in high selectivity. Furthermore, various other alcohols were applied besides methanol, to obtain 2-alkyl- and 1,2-dialkylbenzimidazoles. Preliminary mechanistic insights into the origins of N-alkylation as well as the reactivity of the nitro derivatives are discussed.
4,5,6,7-tetrahydrobenzimidazole derivatives as 5HT3 -antagonists
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, (2008/06/13)
4,5,6,7-Tetrahydrobenzimidazole derivatives represented by general formula (I) STR1 wherein groups represents the following: R1, R2, R3 : independently represent hydrogen atom, hydroxy group, a halogen atom, a lower alkyl
