The free radical rearrangements involving two kinds of group IV elements, $R_3Sn$ and $R_3Ge$ group were studied.
1,5-$Bu_3Sn$ group transfer from enoxy oxygen to nitrogen proceeded preferentially over direct reduction. 1,5-$Bu_3Sn$ group transfer from allylic carbon to nitrogen was found to give a monomer amine and dimer in considerable yield.
1,6-$Bu_3Sn$ group transfer from enoxy oxygen to nitrogen didn``t occur in azetidinyl aldehyde. The generated intermediate seems to be fragmented. That is, it was thought that the reaction proceeded by direct reduction and fragmentation of the intermediate radical to the products.
In keto-aziridine, 1,5-$Ph_3Ge$ group transfer from enoxy oxygen to nitrogen didn``t occur and the reaction proceeded very slowly to give the product by direct reduction in low yield.