Reversible transformation of self-assemblies and fluorescence by protonation–deprotonation in pyrimidinylene–phenylene macrocycles

We describe herein that the self-assembled nanoobjects based on pyrimidinylene-phenylene macrocycles, 1 and 2, which possess the capability to respond to acid-stimuli by proton binding, can undergo reversible transformation of self-assemblies and fluorescence switching by protonation-deprotonation.