Reaction of (Me(3)P)(3)RhCl with (THF)(3)LiSi(SiMe(3))(3) generates the thermally unstable complex (Me(3)P)(3)RhSiMe(2)SiMe(SiMe(3))(2) (1), probably via a series of 1,2- and 1,3-migrations. The analogous iridium reaction results in a similar rearrangement to give the iridacycle (Me(3)P)(3)(H)IrSiMe(2)SiMe(SiMe(3))SiMes(2)CH(2) as a mixture of diastereomers (2a,b), which is catalytically converted to an, equilibrium mixture by hydrogen.