title: Thermal and palladium-catalyzed [3 + 2] synthesis of cyclopentadienone acetals from cyclopropenone acetals and acetylenes.
abstract: [reaction: see text] Substituted cyclopentadienone acetals (CPDAs) were synthesized by a thermal or palladium-catalyzed [3 + 2] cycloaddition reaction of a substituted cyclopropenone acetal to an electron-deficient acetylene. The synthesis afforded di-, tri-, and tetra-substituted CPDAs of considerable structural varieties that undergo Diels-Alder reaction to produce bicyclo[2.2.1]heptenes.
authors.affiliation: Department of Chemistry, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Isobe
authors.forename: Sota
authors.initials: S
authors.lastname: Sato
authors.forename: Takatsugu
authors.initials: T
authors.lastname: Tanaka
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Tokuyama
authors.forename: Eiichi
authors.initials: E
authors.lastname: Nakamura