title: Intermolecular oxonium ylide mediated synthesis of medium-sized oxacycles.
abstract: Detailed in this account are our efforts toward efficient oxacycle syntheses. Two complementary approaches are discussed, with both employing chemoselective allyl ether activation and rearrangement as the key step. Vinyl substituted oxiranes and oxetanes provide a single step access to dihydropyrans and tetrahydrooxepines. Oxiranes proved to be poor substrates, while oxetanes were slightly better. An alternative approach using substituted allyl ethers proved successful and addressed the limitations encountered in the ring expansions.
authors.affiliation: Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Mack
authors.forename: Lindsay A
authors.initials: LA
authors.lastname: Batory
authors.forename: Jon T
authors.initials: JT
authors.lastname: Njardarson