C2-symmetric H-Bonding Benzene Core Motif Promotes Rapid Growth of Long Supramolecular Fibers from Amphiphilic Polymers

Abstract

Strong hydrogen bonds are key non‑covalent interactions that direct molecules into ordered supramolecular assemblies. C3‑symmetric benzene derivatives are a widely used motif to generate building blocks for helical supramolecular fibers, including amphiphilic supramolecular polymer bottlebrushes. In this work, we introduce the benzene diurea monoamide (BDUA) motif, which disrupts the C3-core symmetry by combining distinct hydrogen‑bonding units. This design substantially simplifies the synthesis of amphiphilic building blocks, enabling multi‑gram‑scale preparation under mild conditions and avoiding labor‑intensive purification procedures. The assembly behavior of BDUA amphiphiles was evaluated through quantum chemical calculations and extensive experimental screening. Computational analysis indicates that, despite the C2-core symmetric substitution pattern, BDUA monomers form strong hydrogen bonds and adopt a helical organization within the supramolecular structure. When transferred into water, these amphiphiles rapidly assemble into long supramolecular fibers, even when initially dissolved in organic solvents and subsequently quenched into aqueous media. Compared to previously reported C3-core symmetric benzene‑based amphiphilic polymer building blocks, BDUA exhibits markedly accelerated assembly kinetics while preserving a non‑dynamic, kinetically trapped fiber structure in water once assembled. Overall, the BDUA motif provides a synthetically scalable and highly effective platform for rapidly generating well‑defined supramolecular polymer fibers, offering an easily accessible alternative to traditional C3-core symmetric structures.