The structures and properties of anionic tryptophan complexes
Loading...
Date
2018
Authors
Ieritano, Christian
Featherstone, Joshua
Carr, Patrick J. J.
Marta, Rick A.
Loire, Estelle
McMahon, Terrance B.
Hopkins, W. Scott
Journal Title
Journal ISSN
Volume Title
Publisher
Royal Society of Chemistry
Abstract
The physicochemical properties of [Trpn–H]− and [Trpn⋯Cl]− (n = 1, 2) have been investigated in a combined computational and experimental infrared multiple dissociation (IRMPD) study. IRMPD spectra within the 850–1900 cm−1 region indicate that deprotonation is localized on the carboxylic acid moiety in [Trpn–H]− clusters. A combination of hydrogen bonding and higher order charge–quadrupole interactions appear to influence cluster geometries for all investigated systems. Calculated global minimum and low energy geometries of [Trp⋯Cl]− and [Trp2⋯Cl]− clusters favour coordination of the halide by the indole NH. [Trp2–H]− and [Trp2⋯Cl]− exhibit additional π–π interactions between the heterocyclic side chains.