Programmed synthesis of triarylnitroimidazoles via sequential cross-coupling reactions

Transition-metal-catalyzed programmed sequential arylation reactions of 2-chloro-4-nitro-1H-imidazoles were achieved. The methods are general and were applied in a chemoselective manner for the synthesis of different multiarylated 4-nitroimidazoles bearing three different aryl groups. A salient feature is Pd-catalyzed hetero-hetero coupling at the C5 position through a NO2 directed cross-dehydrogenative coupling (CDC) approach.