title: Enantioselective copper-catalyzed carboetherification of unactivated alkenes.
abstract: Chiral saturated oxygen heterocycles are important components of bioactive compounds. Cyclization of alcohols onto pendant alkenes is a direct route to their synthesis, but few catalytic enantioselective methods enabling cyclization onto unactivated alkenes exist. Herein reported is a highly efficient copper-catalyzed cyclization of γ-unsaturated pentenols which terminates in C-C bond formation, a net alkene carboetherification. Both intra- and intermolecular C-C bond formations are demonstrated, thus yielding functionalized chiral tetrahydrofurans as well as fused-ring and bridged-ring oxabicyclic products. Transition-state calculations support a cis-oxycupration stereochemistry-determining step.
authors.affiliation: Department of Chemistry, The State University of New York at Buffalo, Buffalo, NY 14260 (USA).
authors.forename: Michael T
authors.initials: MT
authors.lastname: Bovino
authors.forename: Timothy W
authors.initials: TW
authors.lastname: Liwosz
authors.forename: Nicole E
authors.initials: NE
authors.lastname: Kendel
authors.forename: Yan
authors.initials: Y
authors.lastname: Miller
authors.forename: Nina
authors.initials: N
authors.lastname: Tyminska
authors.forename: Eva
authors.initials: E
authors.lastname: Zurek
authors.forename: Sherry R
authors.initials: SR
authors.lastname: Chemler
mesh_terms: D000475:Alkenes / Q000737:chemistry*; D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D003500:Cyclization; D004987:Ethers / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D000475:Alkenes; D004987:Ethers; D003300:Copper
keywords: alkenes; asymmetric catalysis; copper; enantioselectivity; heterocycles