Efficient and selective rhodium-catalyzed cyanation of chelation-assisted C-H bonds of alkenes has been accomplished using environmentally benign N-cyano-N-phenyl-p-methylbenzenesulfonamide (NCTS) as a cyanating reagent. The developed methodology tolerates various functional groups and allows the synthesis of diverse substituted acrylonitriles in good to excellent yields. Furthermore, the potential of the methodology was demonstrated through the formal synthesis of chlorpheniramine-based antagonist. © 2015 American Chemical Society.