Solvent-dependent metal-free chemoselective synthesis of benzimidazoles and 1,3,5-triarylbenzenes from 2-amino anilines and aryl alkyl ketones catalyzed by I2

Abstract A solvent-dependent I2-catalyzed chemoselective reaction was developed for the synthesis of benzimidazoles and 1,3,5-triarylbenzenes via the annulation of 2-amino anilines and aryl alkyl ketones or the cyclization of aryl alkyl ketones, respectively. With 1,4-dioxane as the solvent, sequential C-N bond formation followed by C(CO)-C(CH3) bond cleavage leads to the formation of benzimidazoles in a highly selective manner while aldol-type self-condensation of aryl alkyl ketones predominates using PhNO2 or PhCl as the solvent to afford 1,3,5-triarylbenzenes.