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Updated: Jun 8, 2026

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
Atropisomerism of aromatic carbamates
Lutz F Tietze1, Heiko J Schuster, J Marian von Hof
1Institut für Organische und Biomolekulare Chemie der Georg-August-Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany. ltietze@gwdg.de
Abstract:
ortho-Haloarylcarbamates like 1-4 show a high rotational barrier about the N--aryl bond of up to 91.6 kJ mol(-1) as found for 1, which was determined by 2D exchange NMR spectroscopy (EXSY). It was further demonstrated that the height of the barrier not only depends on the substituents at the axis of chirality, but is also influenced by electronic effects.
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