A palladium-catalyzed 1,1-carbocyanation of allyl carbonate by alpha-quaternary alpha-isocyanoacetate was developed. Formation of ketenimine followed by homolysis of the C-N bond and recombination of the resulting caged radical pair was proposed to account for the formation of the unusual coupling product, the beta-cyano-gamma,delta-unsaturated ester. (C) 2018 Elsevier Ltd. All rights reserved.