Homolytic 1,5-transfer of the Bu3Sn and Ph3Ge group from enoxy oxygen and allylic carbon to sulfonyl nitrogen were studied. We found that 1,5-Bu3Sn transfers from enoxy oxygen or allyl carbon to sulfonyl nitrogen occurred cleanly, whereas a reaction of a keto-aziridine with Ph3GeD under the radical conditions did not take place. (C) 2001 Published by Elsevier Science Ltd.