Beschreibung:
For the PE‐spcctroscopic search for H2SiCH2‐generating reactions its first ionization energy was initially estimated by quantum chemical ab initio methods. In a wide range of pyrolysis experiments no reproducible bands could be observed in the expected region. A new band with vibrational fine structure, however, occurred on thermal retrodiene cleavage of the silabicycle (1), X = H (see previous communication). The assignment is supported by further arguments.