Spirocyclic metal silylamides with spiro[3.3]heptane structure, M′ Si, Ge, Sn, Ti, Zr and Hf, have been prepared. Except for the Si derivative, the synthesis involved the reaction of the appropriate M′Cl 4 with Me 3 SiN(M)SiMe 2 -N(M)SiMe 3 , M Li, Na. The M′ Si ...