Regioselective C−H Xanthylation as a Platform for Polyolefin Functionalization

Polyolefins that contain polar functional groups are important materials for next-generation lightweight engineering thermoplastics. Post-polymerization modification is an ideal method for the incorporation of polar groups into branched polyolefins; however, it typically results in chain scission events, which have deleterious effects on polymer properties. Herein, we report a metal-free method for radical-mediated C−H xanthylation that results in the regioselective functionalization of branched polyolefins without coincident polymer-chain scission. This method enables a tunable degree of polymer functionalization and capitalizes on the versatility of the xanthate functional group to unlock a wide variety of C−H transformations previously inaccessible on branched polyolefins.