Open AccessInfluence of Ag + on the Magnetic Response of [2.2.2]Paracyclophane: NMR Properties of a Prototypical Organic Host for Cation Binding Based on DFT Calculations
Author(s) -
MacLeod Carey Desmond,
Gomez Tatiana,
MoralesVerdejo Cesar,
MuñozCastro Alvaro
Publication year - 2015
Publication title -
chemistryopen
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.644
H-Index - 29
ISSN - 2191-1363
DOI - 10.1002/open.201500106
Subject(s) - chemistry , shielding effect , electromagnetic shielding , host (biology) , tensor (intrinsic definition) , chemical physics , metal , molecule , proton nmr , nuclear magnetic resonance spectroscopy , density functional theory , computational chemistry , crystallography , nuclear magnetic resonance , stereochemistry , materials science , organic chemistry , physics , ecology , mathematics , pure mathematics , composite material , biology
The complexation of metal cations into a host–guest situation is particularly well exemplified by [2.2.2]paracyclophane and Ag I , which leads to a strong cation–π interaction with a specific face of the host molecule. Through this study we sought a deeper understanding of the effects the metal center has on the NMR spectroscopic properties of the prototypical organic host, generating theoretical reasons for the observed experimental results with an aim to determine the role of the cation–π interaction in a host–guest scenario. From an analysis of certain components of the induced magnetic field and the 13 C NMR shielding tensor under its own principal axis system (PAS), the local and overall magnetic behavior can be clearly described. Interestingly, the magnetic response of such a complex exhibits a large axis‐dependent behavior, which leads to an overall shielding effect for the coordinating carbon atoms and a deshielding effect for the respective uncoordinated counterparts, evidence that complements previous experimental results. This proposed approach can be useful to gain further insight into the local and overall variation of NMR shifts for host–guest pairs involving both inorganic and organic hosts.