Tetraphenylethylene‐Based Hydrogen‐Bonded Organic Frameworks (HOFs) with Brilliant Fluorescence

Abstract

By synergistically employing four key strategies: (I) introducing tetraphenylethylene groups as the central core unit with aggregation‐induced emission (AIE) properties, (II) optimizing the π‐conjugated length by extending the building block branches, (III) incorporating flexible groups containing ethylenic bonds, and (IV) applying crystal engineering to attain dense stacking mode and highly twisty conformation, we successfully synthesized a series of hydrogen‐bonded organic frameworks (HOFs) exhibiting exceptional one/two‐photon excited fluorescence. Notably, when utilizing the fluorescently superior building block L2, HOF‐LIFM‐7 and HOF‐LIFM‐8 exhibiting high quantum yields (QY) of 82.1% and 77.1%, and ultrahigh two‐photon absorption (TPA) cross‐sections of 148959.5 GM and 123901.1 GM were achieved. These materials were successfully employed in one and two‐photon excited lysosome‐targeting cellular imaging. It is believed that this strategy, combining building block optimization and crystal engineering, holds significant potential for guiding the development of outstanding fluorescent HOF materials.

Polyfunctional Arylamine Based Nanofiltration Membranes with Enhanced Aggressive Organic Solvents Resistance

“…Furthermore, a slight enhancement of fluorescence intensity on the TFC-TAPE 0.25 membrane surface was also attributed to the substituent extension of TPE. 56 It further demonstrates the formation of oligomers and linear polymer chains at this concentration. The unevenly distributed fluorescence intensity in Figure 5a corresponded to the sporadic protrusion in the SEM image (Figure 1e).…”

“…On the other hand, linear and lower weight polyamide molecular fragments within the polyamide layer, similar to tetrastyrene derivatives with extended substituents, still exhibited fluorescence emissive. 42,56 In summary, due to its non-invasive detection and high sensitivity, fluorescence imaging technology has breakthrough significance for rapid acquisition of dynamic information in the process of TFC membrane preparation and optimization. An OSN membrane with high solvent resistance and stability was successfully fabricated using a polyfunctional arylamine TAPE.…”

Multiple non-covalent-interaction-directed supramolecular double helices: the orthogonality of hydrogen, halogen and chalcogen bonding

“…Hydrogen bonding (HB), 1–8 halogen bonding (XB) 9–14 and chalcogen bonding (ChB), 15–22 three prominent non-covalent interactions that are weaker than covalent bonds, but can efficiently induce monomer aggregation, have been highly anticipated in self-assembly chemistry over the past two decades. Since the discovery of the double helical structure of DNA by Watson and Crick, 23 chemists have been drawn to design simple linear molecules that are able to form artificial helices.…”

“…Additionally, Hirshfeld surface analysis has been widely used in recent years as an intuitive approach to quantify and visualize various types of intermolecular interactions in crystals. 53 The interaction sites of XB and ChB can be clearly observed from the Hirshfeld surfaces of the molecules of compounds 1 and 3 (Fig. S54, ESI†).…”