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Hankuk University of Foreign Studies

3 ARTICLES PUBLISHED IN JoVE

JoVE Journal

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles

¹Department of Chemistry, North Eastern Regional Institute of Science and Technology, ²Department of Chemistry, Hankuk University of Foreign Studies

Bicyclic aziridinium ions such as 1-azoniabicyclo[4.1.0]heptane tosylate were generated from 2-[4-tolenesulfonyloxybutyl]aziridine, which was utilized for the preparation of substituted piperidines and azepanes via regio- and stereospecific ring-expansion with various nucleophiles. This highly efficient protocol allowed us to prepare diverse azaheterocycles including natural products such as fagomine, febrifugine analogue and balanol.

Chemistry

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine

Nikhil Srivastava¹, Hyun-Joon Ha¹

¹Department of Chemistry, Hankuk University of Foreign Studies

In this study, we prepare both enantiomers of aziridine-2-carboxylate, which are used in the asymmetric synthesis of alkaloids, including biemamide B and D, and (-)-epiallo-isomuscarine.

Chemistry

Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions

Yeongjin Lee¹, Huimyoung Byeon¹, Hyun-Joon Ha², Jung Woon Yang¹

¹Department of Energy Science, Sungkyunkwan University, ²Department of Chemistry, Hankuk University of Foreign Studies

Contiguous bisaziridines containing non-activated and activated aziridines were synthesized by asymmetric organocatalytic aziridinations and then subjected to chemoselective ring-opening reactions under acidic or basic conditions. The non-activated aziridine ring opens with less reactive nucleophiles under acidic conditions, whereas the activated aziridine ring opens with more reactive nucleophiles under basic conditions.