Transition-Metal-Free C-H/C-Li Coupling of Nonaromatic 2H-Imidazole 1-Oxides with Pentafluorophenyl Lithium in the Design of Novel Fluorophores with Intramolecular Charge Transfer Effect.

Methodology of nucleophilic substitution of hydrogen (SNH) was first applied for the direct modification of nonaromatic 2H-imidazoles to afford novel polyfluoroarylated azaheterocycles. Scope, tolerance for these transition-metal-free C-H/C-Li coupling reactions, and photophysical properties for the novel 4-(perfluorophenyl)-5-aryl-2H-imidazoles were comprehensively studied. In particular, some of the obtained perfluoroaryl-substituted 2H-imidazoles were found to be of particular interest as promising push-pull fluorophore systems in the design of fluorometric sensor materials due to the effect of intramolecular charge transfer.