title: Do secondary orbital interactions really exist?
abstract: A revision of the most typical examples used to illustrate the existence of secondary orbital interactions (SOI) has been achieved. However, our analysis indicates that no conclusive evidence can be obtained from these cases. All five examples proposed by Woodward and Hoffmann in The Conservation of Orbital Symmetry have been revisited. A combination of well-known mechanisms (such as solvent effects, steric interactions, hydrogen bonds, electrostatic forces, and others) can be invoked instead to justify the endo/exo selectivity of Diels-Alder reactions.
authors.affiliation: Departamento de Química Orgánica, Instituto de Ciencia de Materiales de Aragón, Facultad de Ciencias, CSIC-Universidad de Zaragoza, E-50009 Zaragoza, Spain.
authors.forename: J I
authors.initials: JI
authors.lastname: García
authors.forename: J A
authors.initials: JA
authors.lastname: Mayoral
authors.forename: L
authors.initials: L
authors.lastname: Salvatella
mesh_terms: D055598:Chemical Phenomena; D002621:Chemistry; D005663:Furans / Q000737:chemistry; D008299:Maleic Anhydrides / Q000737:chemistry; D055672:Static Electricity; D013816:Thermodynamics
chemical_list: D005663:Furans; D008299:Maleic Anhydrides; C039281:furan