Premium
Eu(fod) 3 binding on the 1 H‐NMR spectra of bis (2′‐ethylbenzoate)ethylene glycol podands
Author(s) -
Ünlü Cüneyt H.,
Yapar Gönül,
Erk Çakıl
Publication year - 2013
Publication title -
magnetic resonance in chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.483
H-Index - 72
eISSN - 1097-458X
pISSN - 0749-1581
DOI - 10.1002/mrc.3904
Subject(s) - chemistry , ethylene glycol , lanthanide , nmr spectra database , proton nmr , ethylene , chemical shift , chelation , chemical stability , oxygen , medicinal chemistry , ionic bonding , polymer chemistry , stereochemistry , spectral line , ion , organic chemistry , catalysis , physics , astronomy
The complexing and selective binding constants of Eu(fod) 3 with bis (2′‐ethylbenzoate)ethylene glycol podands having one to four oxyethylene groups was observed on their 1 H‐NMR spectra at 250 MHz and 295 K in CDCl 3 . The Eu(fod) 3 interaction displayed the selective binding role of oxygen on H 2 C–O–CH 2 backbones with referring the 1 H chemical shifts. The estimated equilibrium constants, K a , of 1:1 ratio of interactions were in accordance with the Eu(fod) 3 ionic radii to bind the oxygen sites depending on the size and conformation of the esters. Esters having one or two ethyleneoxy groups gave mainly 2:2 complexes using ester sites. The minimum lanthanide‐podand ester distance displayed the maximum stability so that ester with four oxyethylene groups was found to bind the Eu(fod) 3 moderately, whereas ester with three oxyethylene groups showed a large induced chemical shift due to the stability of Eu 3+ complexes with larger ethyleneoxy groups. Copyright © 2012 John Wiley & Sons, Ltd.