407626-74-8

Upstream product

• 100-43-6 4-vinylpyridine 
• 523-27-3 9,10-Dibromoanthracene 

Relevant academic research and scientific papers

π-Stacking Conversion and Enhanced Force-Stimuli Response of a Divinylanthracene Derivative in a Hydrogen-Bonded Framework

Hydrogen bond-induced π-stacking conversion was used to achieve an enhanced force-stimuli response of 9,10-bis(2-(pyridin-4-yl)vinyl)anthracene (BP4VA). In BP4VA crystals, the molecules adopted a J-aggregate pattern, and no overlap between the central anthracene planes was observed. Trimesic acid (TA) as a hydrogen bond donor could promote the transformation of the π-stacking type of BP4VA as a hydrogen bond acceptor. It was found that TA and BP4VA molecules formed two-dimensional lamellar hydrogen-bonded frameworks with large windows, which were filled by BP4VA molecules belonging to other layers. Within such three-dimensional packing, J-aggregate stacking type of BP4VA converted into a mixture of J-type and H-type dimers. Moreover, BP4VA adopted a highly twisted conformation, and π-πinteraction between them was very weak. So, the hydrogen-bonded complex emitted a short wavelength fluorescence. More importantly, the yellow hydrogen-bonded complex turned into red solids under force stimuli, and its fluorescence had a fairly large shift of more than 110 nm. This is in contrast with a spectral shift of 43 nm from the sheared neat BP4VA crystals. Quantum chemical calculation and spectral observations implied that the planarization, shortened π-distance, and large overlap between anthracence units should be responsible for the large spectral shift. The results imply that the appropriate acid as a hydrogen bond donor might help distyrylanthracene derivatives possess outstanding functions.

Enhanced emission of a pyridine-based luminogen by hydrogen-bonding to organic and polymeric phenols

Fluorescent bis(pyridinylvinyl)anthracene (An2Py) with two pyridine terminals was synthesized and used to prepare miscible blends with hydroxyl-containing components (organic bisphenol A (BPA) and polymeric poly(vinyl phenol) (PVPh)) through the facile intermolecular hydrogen-bond (H-bond) interactions between the pyridine and the hydroxyl functions. Before blending, the solution of An2Py already emits appreciably due to its aggregation-induced emission enhancement (AIEE) behavior; after blending with the hydroxyl components, the fluorescence can be further intensified due to the restricted molecular rotation, which leads to the blockage of non-radiative decay channels, imposed by the H-bond interactions. The role of the H-bonding on the restricted molecular rotation of the An2Py/BPA (and the An2Py/PVPh) blends was characterized by solution 1H NMR and solid infrared spectroscopy. The effectiveness of the organic BPA and the polymeric PVP as molecular anchors to lock the free rotation of the An2Py luminogen were compared and discussed in this study.