Copper‐Catalyzed Arylation of Cyclic and Bridged Diamines for Drug Discovery

Cyclic diamines are a privileged scaffold in medicinal chemistry, widely used to modulate physicochemical properties and as linker units in bifunctional molecules such as Proteolysis Targeting Chimeras. Existing approaches for aryl functionalization of these motifs rely on S N Ar or Buchwald–Hartwig amination, but methods for cyclic and bridged cyclic diamines remain underdeveloped. We report an operationally simple, ligand‐free copper‐catalyzed Chan–Lam amination that couples arylboronic acids with a broad range of cyclic diamines under mild conditions. The protocol tolerates diverse functional groups, including halides and heteroaryl motifs, delivering pharmaceutically relevant building blocks in good yields. Notably, this strategy enables the first general access to bridged cyclic aryldiamines via Chan–Lam coupling, expanding the scope of this transformation. This method complements existing approaches and provides a practical route to complex diamine architectures for medicinal chemistry applications.