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Isotope effects and mechanism of the asymmetric BOROX Bronsted 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.

SUBMITTER: Vetticatt MJ

PROVIDER: S-EPMC3692281 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature

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Isotope effects and mechanism of the asymmetric BOROX Brønsted acid catalyzed aziridination reaction.

Vetticatt Mathew J MJ Desai Aman A AA Wulff William D WD

The Journal of organic chemistry 20130521 11

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 rin ...[more]

PMID: 23687986

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