Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. A xanthate-based oxidative radical process for the direct alkylation of the coumarin ring system is presented. In the reaction, a vinylic and unactivated C-H bond of the coumarin system is replaced by an α-acyl functionality under neutral conditions. This reaction has a high reaction site selectivity, which can realize alkylation at the C-3 position. A vinylic and unactivated C-H bond of the coumarin system is replaced by an alkyl functionality trough a xanthate-based radical reaction (DLP = dilauroyl peroxide).