Base/DMSO‐Promoted Synthesis of Benzo[4,5]imidazo[2,1‐a]isoquinolines via C−C Bond Formation

In this study, a synthetic method to access benzo[4,5]imidazo[2,1‐a]isoquinolines is developed by the reaction of 2‐(2‐bromoaryl)benzimidazoles with 1,3‐diketones under basic conditions. A reaction pathway involving the initial formation of a C−C coupled intermediate by nucleophilic aromatic substitution and subsequent deacylative cyclocondensation is proposed for this process.