Cation-π Interactions between a Noble Metal and a Polyfunctional Aromatic Ligand: Ag+ (benzylamine)

Chemistry. 2022 Jun 10;28(33):e202200300. doi: 10.1002/chem.202200300. Epub 2022 May 5.

Abstract

The structure of an isolated Ag+ (benzylamine) complex is investigated by infrared multiple photon dissociation (IRMPD) spectroscopy complemented with quantum chemical calculations of candidate geometries and their vibrational spectra, aiming to ascertain the role of competing cation-N and cation-π interactions potentially offered by the polyfunctional ligand. The IRMPD spectrum has been recorded in the 800-1800 cm-1 fingerprint range using the IR free electron laser beamline coupled with an FT-ICR mass spectrometer at the Centre Laser Infrarouge d'Orsay (CLIO). The resulting IRMPD pattern points toward a chelate coordination (N-Ag+ -π) involving both the amino nitrogen atom and the aromatic π-system of the phenyl ring. The gas-phase reactivity of Ag+ (benzylamine) with a neutral molecular ligand (L) possessing either an amino/aza functionality or an aryl group confirms N- and π-binding affinity and suggests an augmented silver coordination in the product adduct ion Ag + ( benzylamine ) ( L ) .

Keywords: IRMPD spectroscopy; ion-molecule reactions; mass spectrometry; non-covalent interactions; structure elucidation.

MeSH terms

  • Benzylamines*
  • Cations / chemistry
  • Ligands
  • Silver* / chemistry
  • Spectrophotometry, Infrared / methods

Substances

  • Benzylamines
  • Cations
  • Ligands
  • Silver