title: Rationalization of Diels-Alder reactions through the use of the dual reactivity descriptor Deltaf(r).
abstract: In this work, the dual descriptor of chemical reactivity, an electronic density-based index, is used to study both the regioselectivity and the stereoselectivity of Diels-Alder reactions. The descriptor has been designed to simultaneously delineate the nucleophilic and electrophilic sites within a molecule. Subsequent pairing between the nucleophilic and electrophilic regions of the reagents predicts the major adducts in all cases studied. Specifically, the descriptor predicts the generation of a ortho-regioisomer when a diene monosubstitued at position 1 by an Electron Donating Group (EDG)/Electron Withdrawing Group (EWG), reacts with a dienophile monosubtituted by an EWG/EDG. Under the same conditions, if the diene is monosubstituted by either an EWG or an EDG at position 2, formation of the para-oriented adduct is predicted. This approach also provides insight into the stereoselectivity. For example, secondary interactions between the non-reactive regions of the reactants explain why the endo stereoisomer is preferred.
authors.affiliation: INAC/SCIB/LAN (UMR-E no. 3 CEA-UJF)), CEA-Grenoble, 17rue des Martyrs, F-38054, Grenoble Cedex 9, France. Christophe.morell@ujf-grenoble.fr
authors.forename: Christophe
authors.initials: C
authors.lastname: Morell
authors.forename: Paul W
authors.initials: PW
authors.lastname: Ayers
authors.forename: André
authors.initials: A
authors.lastname: Grand
authors.forename: Soledad
authors.initials: S
authors.lastname: Gutiérrez-Oliva
authors.forename: Alejandro
authors.initials: A
authors.lastname: Toro-Labbé