title: Asymmetric synthesis of cyclopropanes and dihydrofurans based on phosphine oxide chemistry.
abstract: The asymmetric synthesis of gamma-azido trans-cyclopropyl ketones is accomplished via a short, simple and efficient sequence. The cyclopropanation step is achieved by an intramolecular nucleophilic ring closure, with a diphenylphosphinate leaving group, to give trans-cyclopropane exclusively. beta-Keto-diphenylphosphine oxides cyclise to form optically active dihydrofurans. All possible diastereoisomers of dihydrofurans can be prepared selectively starting from the same olefin.
authors.affiliation: University Chemical Laboratory, Lensfield Road, Cambridge, UKCB2 1EW. djf34@cam.ac.uk
authors.forename: David J
authors.initials: DJ
authors.lastname: Fox
authors.forename: Sean
authors.initials: S
authors.lastname: Parris
authors.forename: Daniel Sejer
authors.initials: DS
authors.lastname: Pedersen
authors.forename: Charles R
authors.initials: CR
authors.lastname: Tyzack
authors.forename: Stuart
authors.initials: S
authors.lastname: Warren