Sodium-23 NMR longitudinal magnetization recovery (L.M.R.) study has been carried out to clarify the sodium ion exchange in ensembles with 1,3-alternate-shaped calixarene 1 for the first time. The line width v1/2 of a sharp singlet for NaClO4 in the absence of 1 is 65 Hz: upon addition of 1 a singlet peak was broadened to 1100 Hz (v1/2). The life times (τ) of Na+ were estimated to be (20-3.8)× 103 s for τA and (5.0-2.0)× 10-3 s for τB, by the simulations of sodium-23 NMR L.M.R. curves. The life times of 1-Na+ Ensemble are larger than those for 18-crown-6. This implies that Na+ cation is bound deeply in the cavity formed by two OCH2CO groups of 1, the complex being classified as a “nest-in-type”.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)