Germyl Radical Cyclization of N-Propargyl Aromatic Amines with Germanes: A Concise Route to Germanium-Containing Quinolines.

Quinolines represent a privileged class of heterocyclic scaffolds widely prevalent in biologically active natural products and marketed pharmaceuticals. Despite their significance, the synthesis of germanium-substituted quinolines through germyl radical cyclization has remained unexplored to date. Herein, we report a dilauroyl peroxide (LPO)-mediated cascade protocol involving germylation, cyclization, and aromatization of N-propargyl aromatic amines with germanes, enabling efficient construction of 3-germanium-substituted quinolines. This transformation proceeds via a radical pathway and features high regioselectivity, broad substrate scope, and good functional group compatibility. Mechanistic investigations indicate that cleavage of the Ge-H bond serves as the rate-determining step.