Synthesis of molecular building blocks is the first step toward designing organic functional materials. Our current research interested focuses on synthetic strategies toward boron-doped and curved p-scaffolds. Starting from borinic acid precursors, heptagon containing polycyclic aromatic hydrocarbons (PAHs) can be synthesised. Besides the interest in optical and electronic properties of these negatively curved PAHs, they also constitute interesting supramolecular building blocks. The negatively curved PAHs represent cutouts of the, so far still imaginary, 3D-p-conjugated carbon structures called “schwarzites”. We envision to approach the synthesis of  these intriguing schwarzites and related materials via a supramolecular templating approach.

M. Schnitzlein et al., Chem. Sci. 2024, 15, 2984–2989; A highly fluorescent bora[6]helicene exhibiting circularly polarized light emission. DOI: 10.1039/D3SC05171D

C. Zhu et al., J. Am. Chem. Soc. 2022, 144, 36, 16282–16286; Supramolecular Substructure of C60-Embedded Schwarzite. DOI: 10.1021/jacs.2c06933

Development of multicomponent architectures containing functional dye-based light harvesting antennae systems and photosensitizers for solar fuel production catalysts. Well-defined dye stacks provide p-stacked supramolecular wires for light-induced charge carrier separation. Metallo-supramolecular systems, like one-dimensional nanofibers, two-dimensional macrocycles, or three-dimensional polyhedra containing ruthenium catalysts accomplish photo- or electrochemical water oxidation.

L. Ernst et al., Nat. Chem. 2025, 17, 767–776; Photoinduced stepwise charge hopping in π-stacked perylene bisimide donor–bridge–acceptor arrays. DOI: 10.1038/s41557-025-01770-7

A. Schulz et al., Chem 2024, 10, 2887–2900; Panchromatic light-harvesting antenna by supramolecular exciton band engineering for heteromeric dye foldamer. DOI:10.1016/j.chempr.2024.05.023

N. Noll et al., Nat. Catal. 2022, 5, 867–877; Enzyme-like water preorganization in a synthetic molecular cleft for homogeneous water oxidation catalysis. DOI: 10.1038/s41929-022-00843-x

Tuning of the photophysical properties of a chromophore host by binding different guest molecules. Design and synthesis of cyclophane or other molecular host systems and investigation of guest binding. Suitable guest molecules can provide access to new radiative relaxation pathways. A special interest lies in  the activation of processes involving triplet states, like thermally activated delayed fluorescence or room temperature phosphorescence, due to their relevance for functional applications.

S. Garain et al., J. Am. Chem. Soc. 2024, 146, 31, 22056–22063; The Delayed Box: Biphenyl Bisimide Cyclophane, a Supramolecular Nano-environment for the Efficient Generation of Delayed Fluorescence. DOI: 10.1021/jacs.4c07730

J. Rühe et al., J. Am. Chem. Soc. 2024, 146, 41, 28222–28232; Guest-Mediated Modulation of Photophysical Pathways in a Coronene Bisimide Cyclophane. DOI: 10.1021/jacs.4c08479

S. Garain, F. Würthner, Chem. Commun. 2025, 61, 3081–3092; Photofunctional cyclophane host–guest systems. DOI: 10.1039/D4CC06070A

Design of functional dye assemblies. Thermodynamic and kinetic investigation of defined assembly formation and characterization of supramolecular structures by  2D NMR, DLS, high-resolution MS, and various microscopy techniques in combination with single crystal x-ray analysis and theory. The defined assemblies in solution provide interesting model systems that often allow to derive structure property relationship which can not be obtained from bulk material.

M.A. Niyas et al., Nature 2025, 637, 854–859; Bilayer nanographene reveals halide permeation through a benzene hole. DOI: 10.1038/s41586-024-08299-8

M.A. Niyas et al., Angew. Chem. Int. Ed. 2024, 63, e202406353; Room-Temperature Near-Infrared Phosphorescence from C64 Nanographene Tetraimide by π-Stacking Complexation with Platinum Porphyrin. DOI: 10.1002/anie.202406353

M. Mahl et al., Nat. Chem. 2022, 14, 457–462; Multilayer stacks of polycyclic aromatic hydrocarbons. DOI: 10.1038/s41557-021-00861-5

Design of supramolecular polymers. Structural characterization as well as mechanistic elucidation, including thermodynamic and kinetic analysis of the self-assembly processes by various spectroscopy techniques as well as isothermal titration calorimetry. A goal is to gain control over the polymerization process via seeded polymerization, kinetic pathways or additives like, e.g., chaperones.

L. Kleine-Kleffmann et al., J. Am. Chem. Soc. 2023, 145, 16, 9144–9151; Controlling the Supramolecular Polymerization of Squaraine Dyes by a Molecular Chaperone Analogue. DOI: 10.1021/jacs.3c01002

M. Wehner et. al., Nature Chem. Rev. 2020, 4, 38-53; Supramolecular polymerization through kinetic pathway control and living chain growth. DOI: 10.1038/s41570-019-0153-8

W. Wagner et. al., J. Am Chem. Soc. 2019, 141, 30, 12044–12054; Supramolecular Block Copolymers by Seeded Living Polymerization of Perylene Bisimides. DOI: 10.1021/jacs.9b04935

Highly purified small molecules can be processed either from solution or by sublimation in vacuum to be utilized as functional solid-state materials in organic thin-film transistors, organic bulk heterojunction solar cells and organic light emitting diodes. The tunability of the properties by the supramolecular packing is investigated by structure property correlations with the help of single crystal and thin-film X-ray analysis.

F. Brust et al., Adv. Optical. Mater 2025, 13, 2402117; Vacuum-Sublimed Cocrystalline Thin Films of Naphthalene Bisimide and Pt(II) Complex for Phosphorescent Light-Emitting Diodes. DOI: 10.1002/adom.202402117

T. Schembri et al., ACS Cent. Sci. 2025, 11, 3, 452–464; Supramolecular Engineering of Narrow Absorption Bands by Exciton Coupling in Pristine and Mixed Solid-State Dye Aggregates. DOI: 10.1021/acscentsci.4c02157

J. H. Kim et al., Adv. Mater. 2021, 33, 2100582; An Efficient Narrowband Near-Infrared at 1040 nm Organic Photodetector Realized by Intermolecular Charge Transfer Mediated Coupling Based on a Squaraine Dye. DOI: 10.1002/adma.202100582