Synthesis of Axially Chiral N-Arylpyrroles through the Enantioselective Annulation of Yne-Allylic Esters with a Cooperative Copper-Squaramide Catalysis

We present a strategy involving central-to-axial chirality conversion for the construction of axially chiral N-arylpyrroles via a cooperative copper-squaramide-catalyzed remote propargylic amination/ring closure/rearomatization cascade from yne-allylic esters. The reaction exhibits excellent chemical efficiency and enantioselectivity, involving good central-to-axial chirality conversion. The use of squaramide as cocatalyst is crucial for the success.