Gold Self-Relay Catalysis Enabling Regioselective Bicyclization toward [5]Azahelicenes.

A gold self-relay catalysis driving a double annulation cascade starting from soft electron-biased 1,2-di(-aminoaryl)alkynes and aldehydes is reported, enabling regioselective access to produce a series of [5]azahelicenes depending on the substitution pattern in generally good yields under mild conditions. This protocol exploits and unifies the π- and σ-Lewis acid capability of gold catalysts, featuring high molecular convergence, broad substrate flexibility, and good functional group compatibility and regioselectivity.