1H-DNMR-Untersuchungen zur inter- und intramolekularen Ligandenmobilität im System Co(II)/[18]Krone-6 / 1H DNMR Studies on the Inter- and Intramolecular Ligand Mobility in the System Co(II)/[18]crown-6

Abstract

The crown ether exchange could be studied in non-coordinating solvents by using the hy­drophobic complex [Co([18]crown-6)] + + . Appreciable outer-sphere association between complex and ligand (K°(50 °C) = 12 ± 0.5 M-1) occurs. This changes the second order rate law to first order (kmono(50 °C) = 7900 ± 500 s_1) with increasing ligand concentration. In the complex mer-[Co([18]crown-6)(CH3OH)3]+ + the stereochemical rearrangement of the uncoordinated part of the crown ether follows an intramolecular pathway via the complex [Co([18]crown-6)]++ as an intermediate product.