β-Perfluoroalkyl Peroxides as Fluorinated C3-Building Blocks for the Construction of Benzo[4,5]imidazo[1,2- a ]pyridines.

An efficient and selective protocol for the synthesis of perfluoroalkyl-group-substituted benzo[4,5]imidazo[1,2- a ]pyridines has been developed in which β-perfluoroalkyl peroxides act as novel fluorinated C3-building blocks to implement regioselective [3 + 3] annulation with 2-cyanomethyl benzimidazole under metal-free conditions. The application of the synthesized perfluoroalkylated BIPs as potent anticancer reagents versus the nonfluorinated ones demonstrated the biological utility of this method.