Intramolecular transamidation enables one-pot synthesis of three chiral, Z-shaped perilenediimides for null-type supramolecular polymer formation

Abstract

Building on the concept of null-type supramolecular polymers, we present herein the synthesis of three isomeric Z-shaped perylenediimides (Z-PDIs 1–3), in which a central PDI core is linked to peripheral trisdodecyloxybenzamide groups by an alanine-derived linker. Interestingly, we discovered that both the starting amines used in the synthesis of symmetric Z-PDIs 1 and 3 can undergo intramolecular transamidation, allowing the one-pot generation of all three isomers 1–3. The self-assembly behavior of these compounds was systematically explored using various spectroscopic methods. In line with our previous observations, the UV-Vis spectra of the aggregates closely resemble those of their monomeric forms, confirming the formation of null-type supramolecular polymers. Moreover, we found that the position of the stereogenic center strongly affects the aggregate stability: the assemblies become more stable when the stereocenter is positioned farther to the PDI core. The lateral benzamide groups facilitate kinetically controlled polymerization through the formation of intramolecular hydrogen-bonded pseudocycles, with the stereocenter's location again playing a key role in modulating the assembly kinetics. Finally, we demonstrate an efficient transfer of point chirality from the alanine-derived linker to the supramolecular structure, resulting in the formation of chiral null-type supramolecular polymers.