title: Counterintuitive substituent effect of the ethynyl group in ion-pi interactions.
abstract: In this article, we report a high-level theoretical study (SCS-RI-MP2(full)/aug-cc-pVTZ) that deals with the substituent effect of the ethynyl group on ion-pi interactions in 1,3,5-triethynylbenzene systems. The ethynyl group is able to act as an electron-withdrawing group, thus favoring the anion-pi interaction. Unexpectedly, it has little influence on the cation-pi interaction. This behavior has been studied by examining the geometrical and energetic features of the complexes, AIM, and charge analyses and partitioning the interaction energy. The simultaneous interaction of 1,3,5-triethynylbenzene with cations and anions by opposite sides of the ring has also been studied.
authors.affiliation: Departament de Química, Universitat de les Illes Balears, E-07122 Palma de Mallorca, Spain.
authors.forename: Xavier
authors.initials: X
authors.lastname: Lucas
authors.forename: David
authors.initials: D
authors.lastname: Quiñonero
authors.forename: Antonio
authors.initials: A
authors.lastname: Frontera
authors.forename: Pere M
authors.initials: PM
authors.lastname: Deyà
mesh_terms: D001555:Benzene Derivatives / Q000737:chemistry*; D003198:Computer Simulation; D018360:Crystallography, X-Ray; D008956:Models, Chemical; D008958:Models, Molecular; D011789:Quantum Theory
chemical_list: D001555:Benzene Derivatives