title: Confined Acid-Catalyzed Asymmetric Carbonyl-Ene Cyclization.
abstract: A highly enantioselective Brønsted acid catalyzed intramolecular carbonyl-ene reaction of olefinic aldehydes has been developed. Using a confined imidodiphosphate catalyst, the reaction delivers diverse trans-3,4-disubstituted carbo- and heterocyclic five-membered rings in high yields and with good to excellent diastereo- and enantioselectivities. ESI-MS, NMR, and DFT mechanistic studies reveal that the reaction proceeds via a stepwise pathway involving a novel covalent intermediate.
authors.affiliation: Max-Planck-Institut für Kohlenforschung , Kaiser Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
authors.forename: Luping
authors.initials: L
authors.lastname: Liu
authors.affiliation: Max-Planck-Institut für Kohlenforschung , Kaiser Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Leutzsch
authors.affiliation: Max-Planck-Institut für Kohlenforschung , Kaiser Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
authors.forename: Yiying
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: Max-Planck-Institut für Kohlenforschung , Kaiser Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
authors.forename: M Wasim
authors.initials: MW
authors.lastname: Alachraf
authors.affiliation: Max-Planck-Institut für Kohlenforschung , Kaiser Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
authors.forename: Walter
authors.initials: W
authors.lastname: Thiel
authors.affiliation: Max-Planck-Institut für Kohlenforschung , Kaiser Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
authors.forename: Benjamin
authors.initials: B
authors.lastname: List