-bound knot the btp units are directed inward to coordinate the metal center, with the strand conformation further stabilized by pyridine-naphthalene π-stacking. In the metal-free knot the btp motifs are rotated outward, with the conformation stabilized by triazole C-H···O hydrogen bonding and naphthalene-naphthalene π-stacking. Reversible metalation and demetalation cleanly interconverts the two knot conformations, establishing btp building blocks as a simple and versatile platform for responsive entangled or woven molecular topologies.
Zhong et al. (Mon,) studied this question.