A threshold for charge transfer in aromatic interactions? A quantitative study of pi-stacking interactions.

Benjamin W Gung; Mehul Patel; Xiaowen Xue

doi:10.1021/jo051808a

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A threshold for charge transfer in aromatic interactions? A quantitative study of pi-stacking interactions.

Benjamin W Gung·Mehul Patel·Xiaowen Xue

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Abstract

[structure: see text] Attractive interactions between substituted arenes in the parallel displaced configuration have been quantitatively studied using triptycene-derived molecular conformational reporters. Charge-transfer bands are observed for models where the interactions are between strong donor and acceptors. Substituent effects on the strength of the aromatic interaction follow opposite trends for strongly electron-deficient arenes and mildly perturbed arenes. The free energy of interactions for models with strong electron donors and acceptors does not follow a linear correlation in the Hammett plot. Electrostatic models alone do not account for the nonlinearity of the free energy-substituents plot.

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Electrons Hydrocarbons, Aromatic Models, Molecular Static Electricity Journal Article Research Support, Non-U.S. Gov't

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Benjamin W Gung, Mehul Patel, Xiaowen Xue. 2005-12-09. A threshold for charge transfer in aromatic interactions? A quantitative study of pi-stacking interactions.. https://doi.org/10.1021/jo051808a

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