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Substituent effects on cation-pi interactions: a quantitative study.

Christopher A Hunter·Caroline M R Low·Carmen Rotger·Jeremy G Vinter·Cristiano Zonta
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Abstract

A synthetic supramolecular complex has been adapted to quantify cation-pi interactions in chloroform by using chemical double-mutant cycles. The interaction of a pyridinium cation with the pi-face of an aromatic ring is found to be very sensitive to the pi-electron density. Electron-donating substituents lead to a strong attractive interaction (-8 kJ/mol(-1)), but electron-withdrawing groups lead to a repulsive interaction (+2 kJ/mol(-1)).

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CationsChloroformDose-Response Relationship, DrugElectronsMagnetic Resonance SpectroscopyModels, ChemicalMutationPyridinium CompoundsThermodynamicsJournal ArticleResearch Support, Non-U.S. Gov't

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Christopher A Hunter, Caroline M R Low, Carmen Rotger, Jeremy G Vinter, Cristiano Zonta. 2002-04-16. Substituent effects on cation-pi interactions: a quantitative study.. https://doi.org/10.1073/pnas.072647899

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