title: A Qualitative Analysis of a "Bora-Brook Rearrangement": The Ambident Reactivity of Boryl-Substituted Alkoxide Including the Carbon-to-Oxygen Migration of a Boryl Group.
abstract: A bora-Brook rearrangement, i.e., the migration of boryl group from a carbon to an oxygen atom in an isolated α-boryl-substituted alkoxide, was examined, and decisive factors for the acceleration of this reaction are disclosed. In this rearrangement, the boryl-substituted alkoxide exhibited ambiphilic reactivity toward electrophiles to afford two types of products, which are electrophiles bound either at the oxygen or at the carbon atom. Using polar solvents, a saturated backbone of the boron-containing heterocycle, or larger alkali metal cations resulted in a significantly increased reaction rate of base-catalyzed isomerization of α-borylbenzyl alcohol including the bora-Brook rearrangement.
authors.affiliation: Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University , 1-13-27 Kasuga, Bunkyo-ku, 112-8551 Tokyo, Japan.
authors.forename: Haruki
authors.initials: H
authors.lastname: Kisu
authors.affiliation: Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, 113-8656 Tokyo, Japan.
authors.forename: Hirotoshi
authors.initials: H
authors.lastname: Sakaino
authors.affiliation: Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, 113-8656 Tokyo, Japan.
authors.forename: Fumihiro
authors.initials: F
authors.lastname: Ito
authors.affiliation: Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University , 1-13-27 Kasuga, Bunkyo-ku, 112-8551 Tokyo, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Yamashita
authors.affiliation: Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, 113-8656 Tokyo, Japan.
authors.forename: Kyoko
authors.initials: K
authors.lastname: Nozaki