C₃‐Symmetrical π‐Scaffolds: Useful Building Blocks to Construct Helical Supramolecular Polymers

Abstract

In this review, we highlight some relevant examples of C3‐symmetrical molecules that have been reported to form supramolecular polymers and helical aggregates. In particular, the number and type of non‐covalent forces are key to bias the supramolecular polymerization leading from a simple isodesmic or cooperative mechanism to a more complex self‐assembly process, i. e. pathway complexity. Furthermore, the attachment of stereogenic centres at the peripheral side chains of the C3‐systems provokes efficient transfer and amplification of chirality phenomena when directional and specific non‐covalent interactions operate. Interestingly, the incorporation of hydrophilic side chains induces the formation of organized aggregates in aqueous media with potential biomedical applications. Overall, the examples shown in this review on C3‐symmetrical scaffolds illustrate the relevance of this molecular shape in the development of functional supramolecular structures.

Supramolecular Polymers – we've Come Full Circle

“…In a recent review, Sanchez described many more important examples of C3‐symmetrical π‐scaffolds as useful building blocks to construct helical supramolecular polymers . This review includes the triphenylamine‐based building blocks as introduced and studied in detail by Giuseppone, which was recently reviewed as well …”

“…[82] This review includes the triphenylamine-based building blocks as introduced and studied in detail by Giuseppone, which was recently reviewed as well. [83] As described above, supramolecular chirality is used to study not only the mechanism of the formation of supramolecular polymers, but is also useful for arriving at detailed insights into the conformational preference of these polymers. Through the years, a variety of stereochemical effects have been studied using chiral supramolecular polymers.…”

From Physical Chemistry to Chemical Physics

“…[1][2][3][4] Dynamic helical polymers are thus usually obtained through aggregation of structurally simple disk-like monomers through a combination of hydrogen bonding and aromatic interactions. [5][6][7][8][9] N,N',N''-Trialkyl benzene-1,3,5-tricarboxamides (alkyl BTAs) are prominent members of this family. 10 Upon stacking, alkyl BTA monomers generate helical rod-like assemblies with a relatively rigid central core because of the strongly-connected amide functions and interacting aromatic rings.…”

Impact of Molecular Size and Shape on the Supramolecular Co‐Assembly of Chiral Tricarboxamides: A Comparative Study

“…[7] Scaffolds like merocyanines, [8] naphthalene bisimides, [9] perylene bisimides, [10] or other p-conjugated systems [11] exemplify the varietyo fm oieties investigatedf or processeso ft ransfer and amplification of chirality. C 3 -symmetric systems like triarylamines are especially relevant in the investigationof chiral amplification,b ecause they readily self-assemble into helical aggregates [12] and, in addition, constitute outstandingp latforms to expandt he knowledgea bout kinetically controlled supramolecular polymerizations. [13] The establishment of structure-function rules in the field of chiral amplification is ac omplex process that requires at horough understanding of the thermodynamic equilibrium affording enantioenriched samples.…”