Facile Synthesis of Polysubstituted Imidazoles through CBr<sub>4</sub>-Mediated Tandem Cyclization of Amidines with 1,3-Dicarbonyl Compounds or Ketones
A facile approach to synthesize polysubstituted imidazoles via CBr4 mediated tandem cyclization of amidine with 1,3-dicarbonyl or ketone is described. This metal-free cascade reaction employed CBr4 as promoter and was carried out with a simple operation under mild conditions.
A new practical carbon-nitrogen bond formation reaction of amidines with ethyl acetoacetate to synthesize imidazoles via oxidative cyclization in the presence of bromide. The reactions were occured under mild and metal-free conditions.
Study of the nucleophilic behaviour of N-phenylbenzamidine towards 1,2-diaza-1,3-dienes: domino reactions for imidazole scaffolds
作者:Orazio A. Attanasi、Silvia Bartoccini、Gianluca Giorgi、Fabio Mantellini、Francesca R. Perrulli、Stefania Santeusanio
DOI:10.1016/j.tet.2010.04.108
日期:2010.7
Depending on the nature of the solvent, alcohol or DMF, N-phenylbenzamidine shows different nucleophilic behaviour towards the conjugated azo–ene system of 1,2-diaza-1,3-dienes. In alcohol it reacts as a nucleophile through the N-phenyl imino nitrogen affording spiro pyrroloimidazoles and 1,3-diphenyl-1H-imidazoles. In DMF, by contrast, it behaves as nucleophile mainly by means of the imino amidino