Structure/energy correlation of bowl depth and inversion barrier in corannulene derivatives: combined experimental and quantum mechanical analysis.
Synthesis of a series of corannulene derivatives with varying bowl depths has allowed for a study correlating the structure (bowl depth) and the energy of bowl inversion. Substituents placed in the peri positions are repulsive and flatten the bowl, thus causing a decrease in the bowl inversion barrier. Conversely, annelation across the peri positions causes a deepening of the bowl, thus an increase in the bowl inversion barrier. Barriers between 8.7 and 17.3 kcal/mol have been measured, and their structures have been calculated using a variety of ab initio methods. The energy profile of an individual corannulene derivative is assumed to fit a mixed quartic/quadratic function from which an empirical correlation of bowl depth and inversion barrier that follows a quartic function is derived. Structure/energy correlations of this type speak broadly of the nature of enzymatic and catalytic activation of substrates.
Seiders
T J
TJ
Contribution from the Department of Chemistry, University of California-San Diego, La Jolla, California 92093-0358, USA.
Baldridge
K K
KK
Grube
G H
GH
Siegel
J S
JS
D055598:Chemical Phenomena; D002627:Chemistry, Physical; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry*; D013816:Thermodynamics
D011084:Polycyclic Aromatic Hydrocarbons; C434863:corannulene