97870-46-7Relevant academic research and scientific papers
RUTHENIUM-CATALYSED REARRANGEMENTS OF AZOBENZENES I. THE PREPARATION OF 1-PHENYLBENZIMIDAZOLES FROM AZOBENZENE DERIVATIVES AND TERTIARY AMINES CATALYSED BY RUTHENIUM COMPLEXES
Spencer, Alwyn
, p. 357 - 366 (1985)
Carbonyl complexes of ruthenium catalyse the formation of 1-phenyl-2-alkylbenzimidazole derivatives from azobenzenes and tertiary amines.The reaction involves rearrangement of the azobenzene moiety to an N-phenyl-1,2-phenylenediamine intermediate which then undergoes alkylation at nitrogen with an alkyl group from the tertiary amine followed by ring closure and aromatization.Various ruthenium complexes serve as catalyst precursors for the reaction and the presence of carbon monoxide is required if good yields are to be obtained.RuCl3 * 3H2O is the preferred catalyst precursor.The yields of products formed show a marked dependence on the substituents in the azobenzene derivative.RhCl3 * 3H2O also catalyses the reaction, though less efficiently than ruthenium complexes.
An easy one-step photocatalytic synthesis of 1-aryl-2-alkylbenzimidazoles by platinum loaded TiO2 nanoparticles under UV and solar light
Selvam,Swaminathan
experimental part, p. 3386 - 3392 (2011/06/28)
One-pot synthesis of disubstituted benzimidazoles from N-substituted 2-nitroanilines or 1,2-diamines with 3-12 nm-sized platinum particles loaded on the TiO2 using solar and UV-A light is described. 1-Aryl-2-alkylbenzimidazoles from 2-nitrodiphenylamines are formed by combined redox photocatalytic reaction, condensation and catalytic dehydrogenation on Pt-TiO2. In case of diamines, this reaction is proceeded by Pt-TiO2 assisted photocatalytic oxidation of an alcohol and a catalytic dehydrogenation of the intermediate on the surface of platinum nanoparticles. In both cases product formation was achieved by tandem photocatalytic and catalytic reactions on Pt-TiO2.
Copper-catalyzed synthesis of benzimidazoles via cascade reactions of o-haloacetanilide derivatives with amidine hydrochlorides
Yang, Daoshan,Fu, Hua,Hu, Liming,Jiang, Yuyang,Zhao, Yufen
, p. 7841 - 7844 (2008/12/22)
(Chemical Equation Presented) We have developed an efficient method for the synthesis of benzimidazoles via cascade reactions of o-haloacetoanilide derivatives with amidine hydrochlorides. The protocol uses 10 mol % CuBr as the catalyst, CS2CO
