title: Intramolecular Photocycloaddition Reactions of Arylcyclopropane Tethered 1-Cyanonaphthalenes.
abstract: Intramolecular photocycloaddition reactions of 1-cyanonaphthalenes bearing an arylcyclopropane containing side chain were investigated. Photoreactions of members of this family in which the arylcyclopropane moiety is bonded at the 2-position of the 1-cyanonaphthalene ring produce head-to-head and head-to-tail 1,2-[3+2] photocycloadducts. On the other hand, substances in this family containing an arylcyclopropane side chain linked to the 4-position of the cyanoarene ring undergo photoreactions to form [4+3] photocycloadducts along with novel nine-membered ring products, which are produced by photochemically induced 10π conrotatory ring opening of the initially formed intramolecular [3+2] cycloadducts. The results of solvent effects and fluorescence investigations along with those focusing on corresponding intermolecular photoreactions demonstrate that the photocycloadducts are formed predominantly through an intramolecular exciplex mechanism and that a photoinduced intramolecular electron transfer pathway via zwitterionic biradicals might be partly responsible for the process when CH3CN is the solvent.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University , 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Maeda
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University , 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan.
authors.forename: Shoji
authors.initials: S
authors.lastname: Matsuda
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University , 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Mizuno