The radical cascade reaction of allyltin with aza-1,6-enyne compounds was studied. Optically active aza-1,6-enynes underwent a radical cascade process in the presence of a high concentration of allyltributyltin to give stannolanes as the major isomer. Piperidines were also observed in small amounts when an allylic unit was introduced stereoselectively to the trans-position of the aryl group at the C2 position. The yield of the products dramatically decreased with concentrations of tin reagent. The E/Z selectivity at the exomethylene group in piperidine depended on the reaction temperature, and it almost doubled when the reaction was carried out at 30 degrees C. In this study, the reaction mechanism of the radical cascade is discussed. (C) 2016 Elsevier Ltd. All rights reserved.