Organofluorine compounds are widely used but pose environmental concerns. We report a base-mediated didefluorination of o-trifluoromethyl benzylamines via difluoroquinone methide intermediates, yielding monofluorinated tricyclic 2H-imidazoles. This efficient method showcases a broad substrate scope and offers mechanistic insight through a 1,4-elimination pathway of two fluoride ions.