title: Rhodium-Catalyzed Asymmetric Cycloisomerization and Parallel Kinetic Resolution of Racemic Oxabicycles.
abstract: While desymmetrizations by intermolecular asymmetric ring-opening reactions of oxabicyclic alkenes with various nucleophiles have been reported over the past two decades, the demonstration of an intramolecular variant is unknown. Reported herein is the first rhodium-catalyzed asymmetric cycloisomerization of meso-oxabicyclic alkenes tethered to bridgehead nucleophiles, thus providing access to tricyclic scaffolds through a myriad of enantioselective C-O, C-N, and C-C bond formations. Moreover, we also demonstrate a unique parallel kinetic resolution, whereby racemic oxabicycles bearing two different bridgehead nucleophiles can be resolved enantioselectively.
authors.affiliation: Department of Chemistry, Davenport Chemical Laboratories, University of Toronto, 80 St. George Street, Toronto, Ontario, M5S 3H6, Canada.
authors.forename: Charles C J
authors.initials: CC
authors.lastname: Loh
authors.affiliation: Department of Chemistry, Davenport Chemical Laboratories, University of Toronto, 80 St. George Street, Toronto, Ontario, M5S 3H6, Canada.
authors.forename: Matthias
authors.initials: M
authors.lastname: Schmid
authors.affiliation: Bayer Pharma Aktiengesellschaft, Aprather Weg 18a, 42113, Wuppertal, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Webster
authors.affiliation: Department of Chemistry, Davenport Chemical Laboratories, University of Toronto, 80 St. George Street, Toronto, Ontario, M5S 3H6, Canada.
authors.forename: Andy
authors.initials: A
authors.lastname: Yen
authors.affiliation: Department of Chemistry, Davenport Chemical Laboratories, University of Toronto, 80 St. George Street, Toronto, Ontario, M5S 3H6, Canada.
authors.forename: Shabnam K
authors.initials: SK
authors.lastname: Yazdi
authors.affiliation: Carbogen Amcis AG, Hauptstraße 171, 4416, Bubendorf, Switzerland.
authors.forename: Patrick T
authors.initials: PT
authors.lastname: Franke
authors.affiliation: Department of Chemistry, Davenport Chemical Laboratories, University of Toronto, 80 St. George Street, Toronto, Ontario, M5S 3H6, Canada. mlautens@chem.utoronto.ca.
authors.forename: Mark
authors.identifier: 0000-0001-9867-9178
authors.initials: M
authors.lastname: Lautens
keywords: alkenes; heterocycles; isomerization; kinetic resolution; rhodium