Characterization of Cyclic N-Acyliminium Ions by Infrared Ion Spectroscopy
Jona Merx1, Kas J Houthuijs2, Hidde Elferink1
1Institute for Molecules and Materials, Synthetic Organic Chemistry, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands.
Abstract:
N-Acyliminium ions are highly reactive intermediates that are important for creating CC-bonds adjacent to nitrogen atoms. Here we report the characterization of cyclic N-acyliminium ions in the gas phase, generated by collision induced dissociation tandem mass spectrometry followed by infrared ion spectroscopy using the FELIX infrared free electron laser. Comparison of DFT calculated spectra with the experimentally observed IR spectra provided valuable insights in the conformations of the N-acyliminium ions.
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