title: Highly selective copper-catalyzed hydroboration of allenes and 1,3-dienes.
abstract: The highly selective copper-catalyzed hydroboration of allenes has been developed. Allylboranes and alkenylboranes were selectively prepared by the judicious choice of catalytic species (copper hydride and boryl copper). Furthermore, two types of alkenylboranes could be selectively synthesized by the choice of an appropriate ligand. Mechanistic studies confirmed that the protonation of a (Z)-σ-allyl copper species, which was isolated and structurally characterized by single-crystal X-ray diffraction, was a key step in these reactions. Besides allenes, this method is also applicable to the selective hydroboration of 1,3-diene derivatives to afford allylboranes and homoallylboranes.
authors.affiliation: Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Semba
authors.forename: Masataka
authors.initials: M
authors.lastname: Shinomiya
authors.forename: Tetsuaki
authors.initials: T
authors.lastname: Fujihara
authors.forename: Jun
authors.initials: J
authors.lastname: Terao
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Tsuji