title: Isotope effects and mechanism of the asymmetric BOROX Brønsted acid catalyzed aziridination reaction.
abstract: The mechanism of the chiral VANOL-BOROX Brønsted acid catalyzed aziridination reaction of imines and ethyldiazoacetate has been studied using a combination of experimental kinetic isotope effects and theoretical calculations. A stepwise mechanism where reversible formation of a diazonium ion intermediate precedes rate-limiting ring closure to form the cis-aziridine is implicated. A revised model for the origin of enantio- and diastereoselectivity is proposed based on relative energies of the ring-closing transition structures.
authors.affiliation: Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States. mjvcatt@gmail.com
authors.forename: Mathew J
authors.initials: MJ
authors.lastname: Vetticatt
authors.forename: Aman A
authors.initials: AA
authors.lastname: Desai
authors.forename: William D
authors.initials: WD
authors.lastname: Wulff
mesh_terms: D000143:Acids / Q000737:chemistry*; D001388:Aziridines / Q000138:chemical synthesis* / Q000737:chemistry; D002247:Carbon Isotopes / Q000737:chemistry; D002384:Catalysis; D003979:Diazonium Compounds / Q000737:chemistry; D007097:Imines / Q000737:chemistry; D007700:Kinetics; D008958:Models, Molecular; D015394:Molecular Structure; D011789:Quantum Theory
chemical_list: D000143:Acids; D001388:Aziridines; D002247:Carbon Isotopes; D003979:Diazonium Compounds; D007097:Imines; C032111:diazoacetic ester