Cyclohexane, with its well‐defined conformers, could be an ideal force‐controlled molecular switch if it were to display substantial differences in electronic and optical properties between its conformers. We utilize σ conjugation in heavier analogues of cyclohexanes (i.e. cyclohexasilanes) and show that 1,4‐disubstituted cyclohexasilanes display configuration‐ and conformation‐dependent variations
decisive role of attractive dispersion forces between neighboring trimethylsilyl groups for product formation in these rearrangement reactions. These attractive dispersion interactions control the course of Wagner–Meerwein rearrangements in oligosilanes, in contrast to the classical rearrangement in hydrocarbon systems, which are dominated by electronic substituent effects such as resonance and hyperconjugation
The novel branched oligosilyltriflates of formula [TfO(Me3Si)2Si]2E (2aâd)
[E = 0 (2a), SiMe2
(2b), GeMe2
(2c), SiMe2âSiMe2
(2d)] and [TfO(Me3Si)2SiSiMe2]3SiMe (9) have been prepared by the protodesilylation of [Ph(Me3Si)2Si]2E (1aâc), [H(Me3Si)2Si]2E (5d) and [Ph(Me3Si)2SiSiMe2]3SiMe (8) using TfOH (CF3SO3H) as reagent in almost quantitative yields. The crystal structure of 2b is reported.
X-ray single-crystal structure analysis. NMR spectroscopic analysis of some Yb–silyl complexes pointed at highly ionic interactions between the silyl ligands and the lanthanides. This bonding picture was supported by DFT calculations at the B3PW91/Basis1 level of theory. Detailed theoretical analysis of a disilylated Eu(II) complex suggests that its singly occupied molecular orbitals (SOMOs) are very