Self-Assembly Synthesis of a [4]Rotacatenane

Recently, we demonstrated that the threading of oligo(ethylene glyco) and urea units into bis-para-xylyl[26]crown-6 (BPX26C6) via Na+ ion template is possible. Herein, we reported a single urea functionality in a dumbbell-shaped guest can be “clipped” by macrocycle generated from a diamine and two dialdehydes through the templating effect of a Na+ ion to self-assembly of a [4]rotacatenane. The resulting imine-containing rotacatenane can be reduced to allow isolation of stable amine-based rotacatenane.