Regioisomers of Aromatic Thioethers with Aggregation‐Induced Phosphorescence

• Published in: ChemPhotoChem Vol. 8; no. 2
• Main Authors: Schmiedtchen, Marco, Maisuls, Iván, Wölper, Christoph, Strassert, Cristian A., Voskuhl, Jens
• Format: Journal Article
• Language: English
• Published: 01.02.2024
• Subjects: Aggregation; Aromatic compounds; Phosphorescence; Photophysics; X-ray diffraction
• ISSN: 2367-0932; 2367-0932
• DOI: 10.1002/cptc.202300209

In this contribution, we describe a library of nine different molecular asterisks, all based on aromatic thioethers. Here, the substitution patterns of the central core unit bearing two nitriles and the rotors featuring methoxy groups were permuted. In addition, the photophysical properties in the solid and aggregated state were investigated. X‐ray diffractometry confirmed the molecular structures. In this frame, the molecular packing in the crystal lattice of the two polymorphs of mNoM was extensively studied and a correlation between photoluminescence and secondary interactions was evaluated. In the solid state, all compounds showed emission in the yellow to red part of the electromagnetic spectrum (555–644 nm) with lifetimes of up to 25 μs and photoluminescence quantum yields of up to 47 %, depending on the substitution pattern. As all the evaluated compounds perform as good emitters with aggregation‐induced phosphorescence (AIP), these compounds can be regarded as multivalent platforms for future applications in supramolecular assemblies or as biomedical labels due to the versatile substitution patterns, manifold geometries as well as appealing photophysical properties. A set of nine different aromatic thioethers was synthesised and investigated regarding their photophysical properties as well as the influence of regioisomerism on their abilities. All compounds showed aggregation‐induced phosphorescence (AIP). X‐ray diffraction analysis delivered a set of polymorphs, helping to understand the underlying connection between molecular packing and emission properties.