title: A halogen bond does not dictate the conformational preferences of cis-1,3-disubstituted cyclohexanes.
abstract: Halogen bonds are defined as interactions between halogens and a Lewis base in which the halogen (X) acts as the electrophilic species, and is typically explained by the presence of a σ-hole at the end of the C-X bond. Despite the important role of the halogen bond in intermolecularly interacting species, e.g. in acid-base reactions, enzyme inhibition and the supramolecular architecture, this interaction was not found to control the conformational equilibrium of some small model molecules, namely cis-1,3-disubstituted cyclohexanes. In addition, the attraction between the electrophilic (σ-hole) and nucleophilic regions is used to explain that the halogen bond was weaker than that in the species with parallel C-X bonds. Therefore, intramolecular halogen bonds should be used with caution to explain the conformational stability of organic compounds.
authors.affiliation: Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, MG, Brazil. matheus@dqi.ufla.br.
authors.forename: Josué M
authors.initials: JM
authors.lastname: Silla
authors.affiliation: Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, MG, Brazil. matheus@dqi.ufla.br.
authors.forename: Matheus P
authors.initials: MP
authors.lastname: Freitas