Helicity interchange in pendant arm tetraaza macrocyclic sodium(I) complexes
Abstract
The temperature dependent 13C NMR spectra of N,N′,N″,N′″-tetrakis(2-hydroxyethyl)-1,4,7,10-tetraazacyclododecanesodium(I) and its 2-methoxyethyl and (S)-2-hydroxypropyl analogues are consistent with helicity interchange of the approximately square antiprismatic isomers occurring much more rapidly than the exchange of Na+ between the solvated and complexed states in methanol in the first two cases, and moderately more so in the last case.