Influence of Solvents (Water, Methanol, Acetone, and Acetonitrile) on the Binding of Copper Ions to Imidazole and Pyridine

摘要

Spontaneous solvent adduction to metal ion-ligand complexes generated using electrospray ionization (ESI) and stored in a quadrupole ion trap mass spectrometer (QIT MS) has been observed in a number of studies.1,2 This behavior is typical for coordinatively unsaturated transition metal ion-ligand complexes that are stored for extended periods of time because the neutral solvent molecules that evaporate from the surface of the droplets during the ESI ion formation process are not efficiently removed via the pumping system and enter the quadrupole ion trap along with the desired ions. In the ion trap, solvent adduction occurs via three-body collisions between the trapped metal ion-ligand complex of interest, a solvent molecule, and the He bath gas.