Green circularly polarized luminescence with a high dissymmetry factor emitted by a [2.2]fluorenonophane

We report the chiroptical properties of enantiopure [2.2]fluorenonophane measured using electronic circular dichroism and circularly polarized luminescence spectroscopy. The target compound exhibited excellent chiroptical properties with high dissymmetry factors of gabs = ±1.3 × 10⁻² and glum = +2.5 × 10⁻²/-2.6 × 10⁻² in a wide range of solvents, accompanied by strong indications of excimer formation. This study emphasizes the outstanding role of [2.2]paracyclophanes as model systems for small molecules with relatively large CPL and expands this compound class by using the easily accessible and modifiable fluorenone derivative.