Optimization of the Cyclic Cross-Hyperconjugation in 1,4-Ditetrelcyclohexa-2,5-dienes
作者:Rikard Emanuelsson、Aleksandra V. Denisova、Judith Baumgartner、Henrik Ottosson
DOI:10.1021/om5001875
日期:2014.6.23
substituted 1,4-disilacyclohexa-2,5-dienes confirm the effect of the E′Me3 substituents, with regard to both electronic excitations and geometries as determined by UV absorption spectroscopy and X-ray crystallography, respectively. At the end, we reveal through computations how electron-donating and electron-withdrawing substituents at the C═C doublebonds influence the electronic properties of the all-carbon
A particularly strong neutral cyclic cross-hyperconjugation was observed in 1c. Its lowest electron binding energy (7.1 eV) is distinctly different from that of 1b (8.5 eV). Molecularorbital analysis reveals a stronger interactionbetween filled π(CC) and π(SiR2) group orbitals in 1c than in 1a and 1b. The energy shift in the highest occupied molecularorbital is also reflected in the first oxidation