Nucleophile‐Dependent Regio‐ and Stereoselective Ring Opening of 1‐Azoniabicyclo[3.1.0]hexane Tosylate |
| |
| Authors: | Mi‐Kyung Ji Dietmar Hertsen Doo‐Ha Yoon Heesung Eum Hannelore Goossens Prof. Dr. Michel Waroquier Prof. Dr. Veronique Van Speybroeck Prof. Dr. Matthias D'hooghe Prof. Dr. Norbert De Kimpe Prof. Dr. Hyun‐Joon Ha |
| |
| Affiliation: | 1. Department of Chemistry, Hankuk University of Foreign Studies, Yongin, 449‐791 (Korea);2. Center for Molecular Modeling, Ghent University, Technologiepark 903, 9052 Zwijnaarde (Belgium), Member of QCMM‐Alliance Ghent‐Brussels;3. Department of Sustainable Organic Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent (Belgium) |
| |
| Abstract: | 1‐[(1R)‐(1‐Phenylethyl)]‐1‐azoniabicyclo[3.1.0]hexane tosylate was generated as a stable bicyclic aziridinium salt from the corresponding 2‐(3‐hydroxypropyl)aziridine upon reaction with p‐toluenesulfonyl anhydride. This bicyclic aziridinium ion was then treated with various nucleophiles including halides, azide, acetate, and cyanide in CH3CN to afford either piperidines or pyrrolidines through regio‐ and stereoselective ring opening, mediated by the characteristics of the applied nucleophile. On the basis of DFT calculations, ring‐opening reactions under thermodynamic control yield piperidines, whereas reactions under kinetic control can yield both piperidines and pyrrolidines depending on the activation energies for both pathways. |
| |
| Keywords: | aziridines density functional theory calculations heterocycles nucleophilic substitution ring expansion ring opening |
|
|
