Cation-Directed Self-Assembly of Macrocyclic Diacetylene for Developing Chromogenic Polydiacetylene

The
cation-directed self-assembly process has emerged as a fascinating
approach for constructing supramolecular architectures and manifested
a diverse range of assembly related applications. Herein, we synthesized
a macrocyclic structure containing bis-amidopyridine and photopolymerizable
diacetylene template, PyMCDA. Owing to the metal coordination affinity
of bis-amidopyridine and the π–π stacking characteristic
of diacetylene template and complementary to the cyclic molecular
framework, Cs+-directed organic nanotubes are generated
via unidirectional self-assembly of PyMCDA. The monomeric PyMCDA nanotubes
are transformed into the covalently cross-linked chromogenic polydiacetylene
nanotubes (PyMCPDA-Cs+) by UV-promoted topochemical polymerization.
The result of a metal–ligand coordination characteristic, geometric
parameters in solid-state assemblies, and topochemical polymerization
behavior reveals a generation of Cs+ ion inserted nanotubes.
Interestingly, PyMCDA-Cs+ nanotubes display thermochromic
property with a brilliant blue-to-red color transition.