Abstract The evaluation of a new azacrown ether ligand bis {[3-(pyridin-4-yl)-1H-pyrazol-1- yl] methyl} diaza-18-crown-6 (b3pd), which contains pendant p-pyridylpyrazole arms connected by diaminomethane linkers, identified a tendency to undergo retro-Mannich fragmentation in the presence of transition-metal ions. However, treatment of b3pd with potassium perchlorate or potassium iodide prior to complexation with transition-metal ions ...
