Synthesis and Characterization of Methoxylated Oligosilyl Group 4 Metallocenes

New methoxylated oligosilyl-substituted metallocenes were synthesized by the reaction of two oligosilanides with different metallocene dichlorides (M = Ti, Zr, and Hf). The first investigated tris(trimethoxysilyl)silanide [(MeO)₃Si]₃SiK (1) underwent a selective monosubstitution to the respective oligosilyl-decorated metallocenes [(MeO)₃Si]₃SiMClCp₂(2-4). Surprisingly, the attempted disilylation with this silanide was not possible. However, in the case of titanocene dichloride, a stable radical [(MeO)₃Si]₃SiTiCp₂(5) was formed. The unsuccessful isolation of bisilylated metallocenes encouraged us to investigate the reactivity of another silanide. Therefore, we synthesized a hitherto unknown disilanide K[(MeO)₃Si]₂Si(SiMe₂)₂Si[(MeO)₃Si]₂K (8), which was accessible in good yields. The reaction of compound 8 and different metallocene dichlorides (M = Ti, Zr, and Hf) gave rise to the formation of heterocyclic compounds 9-11 in good yields.