The title compounds possess unusual orbital interactions. A p-pi type interaction which incorporates both a transannular and circumannular component and a non-bonding circumannular interaction from the lone electron pairs on the opposite ends of the ring interacting via the ring carbon p-orbitals of proper symmetry. Variable temperature NMR was employed to examine the effect of the non-bonding interaction of inversion through nitrogen on the imine chromophore. A plot of In k vs 1/T allowed for the determination of Ea from the slope and the free energy of activation AG was calculated from the coalescence temperature. The magnitude of long range circumannular interaction is evaluated and used in order to explain the energy differences for nitrogen inversion in the title compounds.
Library of Congress Subject Headings
Molecular orbitals; Imines
Department, Program, or Center
School of Chemistry and Materials Science (COS)
Naik, Arati, "The Study of circumannular orbital interactions in the imine derivatives of 2,2,4,4-tetramethyl-1,3-cyclobutanedione" (1998). Thesis. Rochester Institute of Technology. Accessed from
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