title: New biphenyl iminium salt catalysts for highly enantioselective asymmetric epoxidation: role of additional substitution and dihedral angle.
abstract: New biaryl iminium salt catalysts for enantioselective alkene epoxidation containing additional substitution in the heterocyclic ring are reported. The effects upon conformation and enantioselectivity of this additional substitution, and the influence of dihedral angle in these systems, has been investigated using a synthetic approach supported by density functional theory. Enantioselectivities of up to 97% ee were observed.
authors.affiliation: School of Chemistry, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK. p.page@uea.ac.uk.
authors.forename: Philip C
authors.initials: PC
authors.lastname: Bulman Page
authors.affiliation: School of Chemistry, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK. p.page@uea.ac.uk.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Bartlett
authors.affiliation: School of Chemistry, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK. p.page@uea.ac.uk.
authors.forename: Yohan
authors.initials: Y
authors.lastname: Chan
authors.affiliation: Department of Chemistry, Nottingham Trent University, Clifton, Nottinghamshire NG11 8NS, UK.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Allin
authors.affiliation: Charnwood Molecular Ltd, 7 Beaumont Court, Prince William Road, Loughborough, Leicestershire LE11 5GA, UK.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: McKenzie
authors.affiliation: Département de Chimie Organique, Université de Genève, Quai Ernest Ansermet 30, CH-1121 Genève 4, Switzerland.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Lacour
authors.affiliation: School of Chemistry, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK. p.page@uea.ac.uk.
authors.forename: Garth A
authors.initials: GA
authors.lastname: Jones