VCD spectroscopy distinguishes the enamine and iminium ion of a 1,1′-binaphthyl azepine

We present a VCD spectroscopic characterization of a chiral 1,1 '-binaphthyl azepine catalyst and show that the VCD spectra of an in situ generated enamine and an ex situ prepared iminium ion are characteristically different. The study highlights the potential of VCD spectroscopy to distinguish such catalytically relevant stable intermediates and that the spectra can be used to determine the species ' dominant conformers in solution.

Automated summary

We present a VCD spectroscopic characterization of a chiral catalyst and show that the VCD spectra of in situ generated enamine and ex situ prepared iminium ion are different. This study highlights the potential of VCD spectroscopy in distinguishing stable intermediates and determining the dominant conformers in solution.