A novel pathway and seeded polymerizations of aggregates at the thermodynamic state for an amido-anthraquinone compound

Abstract

Monomers undergo supramolecular polymerizations via diverse pathways conferring pathway complexity; deciphering the complexity has been an intriguing and fundamental subject of various studies. In this work, a functional anthraquinone molecule with a tridodecyloxybenzamide group was rationally designed and synthesized, and the closed monomeric conformer with an intramolecular H-bond was controlled by temperature change. Aggregates stabilized with the intramolecular H-bond were prepared by the temperature control approach, and the thermodynamic transformation was found to proceed according to the nucleation–elongation supramolecular polymerization model. On the other hand, the kinetic transformations from the monomer to the aggregates were affected drastically by the temperature and monomer concentrations, and could be triggered by the seeds of the aggregates. In addition, the triggered transformation processes were rationalized by a seeded polymerization model. A polymerization mechanism for the formation of the aggregates at the thermodynamic state was proposed involving a novel pathway in which an intramolecular H-bond remained intact. The designing strategy of the monomeric conformer is anticipated to diversify the pathway complexity in supramolecular polymerizations possibly providing a new methodology for the synthesis of other building blocks.