Modular <i>Ipso</i> / <i>Ortho</i> Difunctionalization of 3-Iodochromones Enabled by Palladium/Norbornene Catalysis for Stereoselective Synthesis of Chromone <i>C</i> -Glycosides

We report a palladium-catalyzed Catellani-type ortho -C–H glycosylation strategy that enables modular ipso / ortho difunctionalization of 3-iodochromones, leading to highly functionalized α- C -chromone glycosides. Notable highlights include the use of ipso -Heck and Sonogashira couplings as flexible termination steps, along with a broad substrate scope, good chemoselectivity, step-economy, and scalability. In addition, our study presents a novel library of 2,3-difunctionalized chromone C -glycoside molecular scaffolds, offering significant potential for future drug discovery applications.