Catalytic Enantioselective Construction of Planar Chiral Heterocyclic [2.2]Paracyclophanes Enabled by Copper-Catalyzed Desymmetric Azide-Alkyne Cycloaddition.

The construction of planar chiral [2.2]paracyclophanes (PCPs) is of great importance due to their intriguing photophysical and optoelectronic properties. However, catalytic asymmetric approaches to access valuable heterocyclic PCPs directly remain underexplored. Herein, we present the enantioselective synthesis of planar chiral triazole-based PCPs via a desymmetrizing copper-catalyzed alkyne-azide cycloaddition (CuAAC) reaction. A diverse range of functionalized optically enriched heterocyclic PCPs is obtained in a highly enantioselective manner under mild conditions. Moreover, this protocol showcases the versatility and efficiency of applying the desymmetric CuAAC reaction in the successful construction of planar chirality.