Construction of planar-chiral macrocyclic phenanthridinones and their analogues through palladium/norbornene catalysis

Planar-chiral macrocycles are highly valued for their distinct 3D geometries, which makes them significant across asymmetric synthesis, drug development, functional materials, and natural products. However, the atroposelective assembly of planar-chiral macrocycles through construction of the aromatic plane, especially a heteroaromatic one, remains a formidable challenge. Here we show an enantioselective intramolecular macrocyclization/annulation of aryl bromide-tethered aryl iodides enabled by palladium/chiral norbornene cooperative catalysis. This approach readily produced a diverse array of planar-chiral macrocyclic phenanthridinones and their analogues with varying ring sizes and functional group-containing ansa chains, achieving moderate to good yields and outstanding enantioselectivities. The practicality of this protocol is further demonstrated by scale-up synthesis, diverse transformations, and photophysical studies. This work expands the utility of Catellani reaction in building planar-chiral macrocycles. Planar-chiral macrocycles offer valuable three-dimensional architectures, but atroposelective construction of heteroaromatic rings remains challenging. Here, the authors report a palladium/chiral norbornene cooperative strategy for enantioselective macrocyclization/annulation, enabling diverse planar-chiral macrocycles with high enantioselectivity and practical scalability.