title: Substituent effects on cation-pi interactions: a quantitative study.
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)).
authors.affiliation: Centre for Chemical Biology, Krebs Institute for Biomolecular Science, Department of Chemistry, University of Sheffield, Sheffield S3 7HF, United Kingdom. C.Hunter@Sheffield.ac.uk
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Hunter
authors.forename: Caroline M R
authors.initials: CM
authors.lastname: Low
authors.forename: Carmen
authors.initials: C
authors.lastname: Rotger
authors.forename: Jeremy G
authors.initials: JG
authors.lastname: Vinter
authors.forename: Cristiano
authors.initials: C
authors.lastname: Zonta
mesh_terms: D002412:Cations; D002725:Chloroform / Q000737:chemistry; D004305:Dose-Response Relationship, Drug; D004583:Electrons; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D009154:Mutation; D011726:Pyridinium Compounds / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D002412:Cations; D011726:Pyridinium Compounds; D002725:Chloroform