The Examination of a Variety of Different Ions Added to the Crown Ether Derivatives with High Field NMR Spectrometer

Abstract

The current study involves the measurements of T-1 relaxation time of complexes three different crown ethers (4-aminobenzo-15-Crown-5, 1-Aza-18-Crown-6, 1-Aza-15-Crown-5) and two different ions sodium perchlorate (NaClO4), lithium perchlorate (LiClO4) by a 400 MHz NMR spectrometer. The association constants (K-a) of the complexes were determined on the basis of the evaluation of these measurements using the Benesi-Hildebrand method that we have modified. These association constants were consistent with those obtained from H-1 NMR titration technique. As a result, it can be speculated that binding constants could be measured using T-1 relaxation time when chemical shifts are very small or cannot be observed.