1,3-Migration of a methyl group from tin to silicon via a cationic intermediate

Reactions of (Me3Si)2C(SnMe3)(SiMe2l) with AgY (Y = O2CMe, O2CCF3, or O3SCF3) give exclusively (Me3Si)3CSnMe2Y; i.e. 1,3-migration of an Me group from an Sn to an Si atom occurs, apparently within an intermediate cation in which an Me group bridges between these atoms.