Threshold dissociation energies of protonated amine/polyether complexes in a quadrupole ion trap

Citations of this article
Mendeley users who have this article in their library.


Electrospray ionization mass spectrometry (ESI-MS) is increasingly used to probe the nature of noncovalent complexes; however, assessing the relevance of gas-phase results to structures of complexes in solution requires knowledge of the types of interactions that are maintained in a solventless environment and how these might compare to key interactions in solution. This study addresses the factors impacting the strength of hydrogen bonding noncovalent interactions in the gas phase. Hydrogen bonded complexes consisting of ammonium ions bound to polydentate ethers are transported to the gas phase with ESI, and energy-variable collisional activated dissociation (CAD) is used to map the relative dissociation energies. The measured relative dissociation energies are correlated with the gas-phase basicities and steric factors of the amine and polyether constituents. To develop correlations between hydrogen bonding strength and structural features of the donor and acceptor molecules, a variety of amines with different gas-phase basicities and structures were selected, including primary, secondary, and tertiary amines, as well as those that are bidentate to promote intramolecular hydrogen bonding. The acceptor molecules are polydentate ethers, such as 18-crown-6. Four primary factors influence the observed dissociation energies of the polyether/ammonium ion complexes: the gas-phase basicities of the polyether and amine, steric effects of the amines, conformational flexibility of the polyethers, and the inhibition of intramolecular hydrogen bonds of the guest ammonium ions in the resulting ammonium/polyether noncovalent complexes. © 2003 American Society for Mass Spectrometry.




David, W. M., & Brodbelt, J. S. (2003). Threshold dissociation energies of protonated amine/polyether complexes in a quadrupole ion trap. Journal of the American Society for Mass Spectrometry, 14(4), 383–392.

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free