Access to Axially Chiral Diaryl Ethers via Catalytic Atroposelective [2+2+2] Cycloaddition of Alkynyloxybenzenes.

Despite the growing importance of axially chiral diaryl ethers, efficient catalytic asymmetric methods for their synthesis remain rare, and existing approaches are largely limited to desymmetrization. Here, we report a direct and atroposelective annulation strategy to address this challenge. Using a rhodium catalyst, this method constructs diaryl ethers bearing C─O chiral axes in a single step from readily accessible phenoxyalkynes and 1,6-diynes. The approach provides a modular and efficient pathway that avoids preassembled chiral precursors, affording atropisomers in high yields with excellent enantiocontrol and chemoselectivity. The synthetic utility of this methodology is further demonstrated by converting the products into valuable chiral building blocks and chiral ligands.