title: Calcium-Catalyzed Synthesis of Polysubstituted 2-Alkenylfurans from β-Keto Esters Tethered to Propargyl Alcohols.
abstract: An efficient synthesis of polysubstituted 2-alkenylfurans using Ca(NTf2)2/KPF6as a catalytic mixture is described. It is based on the cycloelimination of readily available propargyl alcohols tethered to β-keto esters under dry conditions to avoid competitive Meyer-Schuster rearrangement. The furan can be further functionalized in situ by a calcium-catalyzed Friedel-Crafts-type reaction with secondary and tertiary alcohols. The title reaction allows for the high-yielding preparation of di-, tri-, and tetrasubstituted 2-alkenylfurans, which are important subunits of bioactive compounds.
authors.affiliation: Institut de Chimie Moléculaire et des Matériaux d'Orsay, CNRS UMR 8182, Univ. Paris-Sud, Université Paris-Saclay, bâtiment 420, 91405, Orsay cedex, France.
authors.forename: Sara P
authors.initials: SP
authors.lastname: Morcillo
authors.affiliation: Institut de Chimie Moléculaire et des Matériaux d'Orsay, CNRS UMR 8182, Univ. Paris-Sud, Université Paris-Saclay, bâtiment 420, 91405, Orsay cedex, France.
authors.forename: David
authors.initials: D
authors.lastname: Leboeuf
authors.affiliation: Institut de Chimie Moléculaire et des Matériaux d'Orsay, CNRS UMR 8182, Univ. Paris-Sud, Université Paris-Saclay, bâtiment 420, 91405, Orsay cedex, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Bour
authors.affiliation: Institut de Chimie Moléculaire et des Matériaux d'Orsay, CNRS UMR 8182, Univ. Paris-Sud, Université Paris-Saclay, bâtiment 420, 91405, Orsay cedex, France.
authors.forename: Vincent
authors.identifier: http://orcid.org/0000-0003-1108-9410
authors.initials: V
authors.lastname: Gandon
keywords: alcohol; calcium; carbocation; cyclization; furan