title: Copper-catalyzed borylation of α-alkoxy allenes with bis(pinacolato)diboron: efficient synthesis of 2-boryl 1,3-butadienes.
abstract: Something solid to build on: 2-Boryl 1,3-butadienes with various substitution patterns were formed in good to high yields in a copper-catalyzed borylation of α-alkoxy allenes with bis(pinacolato)diboron (see scheme; Bn=benzyl, pin=pinacolate, L is an N-heterocyclic carbene ligand). The products were found to be useful intermediates for the synthesis of cyclic vinyl boranes, α,β-unsaturated ketones, and functionalized multisubstituted dienes.
authors.affiliation: Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510 (Japan) http://twww.ehcc.kyoto-u.ac.jp/; Present Address: Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510 (Japan).
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Semba
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
keywords: allenes; boron; copper; organoboranes; synthetic methods