title: Triflic acid-catalyzed additions of 2-alkoxycarbonyl allylboronates to aldehydes. Study of scope and mechanistic investigation of the reaction stereochemistry.
abstract: The substrate scope and the effect of substrate on the observed inversion of stereoselectivity in the triflic acid-catalyzed allylboration reaction between 2-alkoxycarbonyl allylboronates and aldehydes are presented. A mechanistic investigation is described so as to confirm the involvement of a carbocation intermediate as the source of stereochemical inversion. This methodology allows a facile access to beta,gamma-disubstituted five-membered ring lactones with an exo-methylene at the alpha-position.
authors.affiliation: Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2.
authors.forename: Tim G
authors.initials: TG
authors.lastname: Elford
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Arimura
authors.forename: Siu Hong
authors.initials: SH
authors.lastname: Yu
authors.forename: Dennis G
authors.initials: DG
authors.lastname: Hall