424799-48-4Relevant articles and documents
A new facile, efficient synthesis and structure peculiarity of quinoxaline derivatives with two benzimidazole fragments
Mamedov, Vakhid A.,Zhukova, Nataliya A.,Syakaev, Victor V.,Gubaidullin, Aidar T.,Beschastnova, Tat'Yana N.,Adgamova, Dil'Bar I.,Samigullina, Aida I.,Latypov, Shamil K.
, p. 1403 - 1416 (2013)
A highly efficient and versatile method for the synthesis of quinoxaline derivatives with two benzimidazole fragments have been developed on the basis of the ring contraction of 3-(benzimidazo-2-yl)quinoxalin-2(1H)-one with 1,2-diaminobenzene and its various types of substituted and condensed derivatives. Owing to the inter- and intramolecular processes, involving self association, proton exchange, conformational, and/or tautomeric exchanges between several forms for most of the bis-benzimidazolylquinoxalines signals of bridged and neighboring carbon atoms and the hydrogen atoms of the neighboring carbon atoms of benzimidazole fragments in the NMR spectra are broadened. The conjugation between the benzimidazole fragments and the quinoxaline core of the molecules is increased from the quinoxaline derivative (10c) to its thiadiazol[f]- (17) and pyrrolo[a]-(19) annulated derivatives, resulting in a greater planarity of the molecule as a whole.
Enantioselective C2-Allylation of Benzimidazoles Using 1,3-Diene Pronucleophiles
Knippel, James Levi,Ye, Yuxuan,Buchwald, Stephen L.
supporting information, p. 2153 - 2157 (2021/04/05)
Although substituted benzimidazoles are common substructures in bioactive small molecules, synthetic methods for their derivatization are still limited. Previously, several enantioselective allylation reactions of benzimidazoles were reported that functionalize the nucleophilic nitrogen atom. Herein we describe a reversal of this inherent selectivity toward N-allylation by using electrophilic N-OPiv benzimidazoles with readily available 1,3-dienes as nucleophile precursors. This CuH-catalyzed approach utilizes mild reaction conditions, exhibits broad functional-group compatibility, and exclusively forms the C2-allylated product with excellent stereoselectivity.
Synthesis of N-alkoxy-substituted 2H-benzimidazoles
Ansari, Nurul H.,S?derberg, Bj?rn C.G.
, p. 4717 - 4720 (2017/11/21)
Treatment of 2-nitro-N-(2-methyl-1-propen-1-yl)benzenamines with potassium tert-butoxide in tert-butanol followed by the addition of an electrophile affords N-alkoxy-2H-benzimidazoles. Electrophiles including methyl iodide, allylic bromides, propargylic bromides, benzyl bromide, and acetyl chloride gave good to excellent yields of product while 1-iodo- and 2-iodo-butane afforded very low yields.
Palladium-catalyzed synthesis of quinoxaline derivatives
Wallace, Jeffery M.,S?derberg, Bj?rn C.G.,Tamariz, Joaquín,Akhmedov, Novruz G.,Hurley, Mathew T.
, p. 9675 - 9684 (2008/12/22)
A palladium-catalyzed reductive N-heteroannulation of enamines derived from 2-nitrobenzenamines forming mixtures of 1,2-dihydroquinoxalines and 3,4-dihydroquinoxalin-2-ones is described. The reactions are performed using bis(dibenzylideneacetone)palladium(0), 1,3-bis(diphenylphosphino)propane, and 1,10-phenanthroline in DMF under 6 atm of carbon monoxide at 70 °C.
