The synthesis, X-ray and spectroscopic analysis, and unusual bonding and structure among heavy group-14 element congeners of allene (heavy allenes) [R2M=M′=MR2; M = M′ = Si (1a), M ) Si, M′) Ge (1b), M = Ge, M′ = Si (1c), and M = M′ = Ge (1d)] are comparatively discussed. Using DFT calculations and PMO theory, the origin of the bent and fluxional skeleton of the heavy allenes is ascribed to the Jahn-Teller distortion associated with the effective π-σ* mixing (π-σ* distortion). This type of distortion is suggested to be a key concept for qualitative description of the unusual bonding of unsaturated compounds of heavy main-group elements.
ASJC Scopus subject areas
- 化学 (全般)