VCD spectroscopy probing of weak intermolecular interactions between copper coordination compounds and N-blocked amino acids

Vibrational and electronic circular dichroism (VCD and ECD) spectroscopic investigations of chiral molecular interactions between copper coordination compounds and N-blocked amino acids were reported. VCD and IR spectra in the region of 1700–1500 cm−1 exhibit abundant information of intermolecular interactions which were insensitive in ECD studies. These signals can be further interpreted by complexation-induced interactions between the copper coordination compounds and amino acids through ion coordination, hydrogen bonding and van der Waals interactions. The results testify the superiority of VCD spectroscopy for detecting weak intermolecular interactions such as in biologically active systems concerning copper ion.

► CD spectroscopy was utilized to probe weak intermolecular interactions in solution.
► The weak intermolecular interactions were clearly evidenced by VCD signal shifts.
► Our results show the superiority of VCD spectroscopy in chiral analysis.