| Abstract
| - Dicyclooctatetraenylmethane (1) and dicyclooctatetraenyldimethylsilane (2) in THF-d8 at 272 Kexist as mixtures of diastereomers in ratios of 1:0.8 and 1:1, respectively. Nine energy minima(four meso and five racemic conformers) were located for each compound by geometry optimizationat the HF/6-31G* level of theory. The effects of torsional strain, steric interactions and dynamicelectron correlation were analyzed. The diastereomeric ratios for 1 and 2 were reproduced reasonablywell from the total energy calculated for each conformer corrected for its conformational enthalpyand entropy contributions. The ratio of rate constants for bond shift (BS) (kBS(1)/kBS(2)) is threetimes greater than the corresponding ratio for ring inversion. This suggests that additionalsubstituent effects, such as π interactions, are operative in the transition state for BS.
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