title: Novel organocatalytic activation of unmodified Morita-Baylis-Hillman alcohols for the synthesis of bicyclic α-alkylidene-ketones.
abstract: The organocatalytic activation of Morita-Baylis-Hillman alcohols via H-bonding-iminium-ion formation is demonstrated for the first time. This activation strategy enables the Morita-Baylis-Hillman alcohols to undergo a formal SN2' reaction. In combination with the well-established enamine reactivity, this creates a new reactivity pattern. The application of this new activation mode for the synthesis of bicyclic α-alkylidene-ketones is demonstrated. The developed reaction sequence proceeds efficiently affording nature-inspired target products with four contiguous stereogenic centers in a highly stereoselective manner.
authors.affiliation: Center for Catalysis, Chemistry Department, Aarhus University, Langelandsgade 140, 8000 Aarhus C (Denmark).
authors.forename: Julian
authors.initials: J
authors.lastname: Stiller
authors.forename: Dorota
authors.initials: D
authors.lastname: Kowalczyk
authors.forename: Hao
authors.initials: H
authors.lastname: Jiang
authors.forename: Karl Anker
authors.initials: KA
authors.lastname: Jørgensen
authors.forename: Łukasz
authors.initials: Ł
authors.lastname: Albrecht
keywords: Morita-Baylis-Hillman adducts; activation strategies; alpha-alkylidene-ketones; asymmetric synthesis; organocatalysis