Anti‐cooperative Self‐Assembly with Maintained Emission Regulated by Conformational and Steric Effects. Issue 17 (2nd March 2022)

• Record Type: Journal Article
• Authors: Helmers, Ingo; Hossain, Muhammad Saddam; Bäumer, Nils; Wesarg, Paul; Soberats, Bartolome; Shimizu, Linda S.; Fernández, Gustavo
• Is Part Of: Angewandte Chemie international edition. Volume 61:Issue 17(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-03-02
• Subjects: Anti-Cooperativity -- BODIPY Dyes -- Conformational Changes -- Self-Assembly -- Hydrogen Bonding; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.202200390
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Herein, we present a strategy to enable a maintained emissive behavior in the self‐assembled state by enforcing an anti‐cooperative self‐assembly involving weak intermolecular dye interactions. To achieve this goal, we designed a conformationally flexible monomer unit 1 with a central 1, 3‐substituted (diphenyl)urea hydrogen bonding synthon that is tethered to two BODIPY dyes featuring sterically bulky trialkoxybenzene substituents at the meso ‐position. The competition between attractive forces (H‐bonding and aromatic interactions) and destabilizing effects (steric and competing conformational effects) limits the assembly, halting the supramolecular growth at the stage of small oligomers. Given the presence of weak dye–dye interactions, the emission properties of molecularly dissolved 1 are negligibly affected upon aggregation. Our findings contribute to broadening the scope of emissive supramolecular assemblies and controlled supramolecular polymerization. Abstract : The fine tuning of emissive properties in the self‐assembled state represents a bottleneck in contemporary supramolecular research. Herein, the effective transfer of emissive behavior from the molecularly dissolved to the aggregated state mediated by the delicate balance between attractive and repulsive interactions is demonstrated, leading to an anti‐cooperative size‐restricted growth with weak dye–dye interactions.