An Approach for Highly Enantioselective Synthesis of -Disubstituted []Paracyclophanes.

Atroposelective synthesis of -disubstituted []paracyclophanes is a difficult task in organic chemistry. We describe a facile approach for the synthesis of -disubstituted []paracyclophanes using Pd-catalyzed enantioselective C-H olefination and sequential reductive cleavage. A wide range of []paracyclophanes was obtained with excellent enantioselectivity. Thermodynamic analysis revealed that the rotational barrier of -disubstituted []paracyclophanes was lower than that of -disubstituted []paracyclophanes. The synthesized planar-chiral [14]paracyclophane showed a bright fluorescence emission and impressive circularly polarized luminescence activity.