Large shape-persistent metal-invertible 15-Nsp2-donor-atom macrocycles functioning as trinucleating ligands

Reaction of 4,6-dihydrazinopyrimidines with 2,6-dicarbonylpyridines produces, under metal-free or template conditions, a new class of [3 + 3] macrocycles with 15 Nsp(2) donor atoms. Nine Nsp(2) atoms are on the external circumference of the macrocycle. The macrocycle can bind metal ions and produce trinuclear complexes along with the motion of the nine outer Nsp(2) atoms to inner positions (a motion of inversion of the macrocycle).