Isotope effects and mechanism of the asymmetric BOROX Brønsted acid catalyzed aziridination reaction.
نویسندگان
چکیده
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.
منابع مشابه
Chiral Brønsted Acid‐Catalyzed Asymmetric Synthesis of N‐Aryl‐cis‐aziridine Carboxylate Esters
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عنوان ژورنال:
- The Journal of organic chemistry
دوره 78 11 شماره
صفحات -
تاریخ انتشار 2013