Solvation-dependent switching of solid-state luminescence of a fluorinated aromatic tetrapyrazole

Abstract

Switchable solid-state fluorescence has been observed as a consequence of reversible solvation.

Hydrogen-Bonded Organic Framework Microlasers with Conformation-Induced Color-Tunable Output

“…Hydrogen-bonded organic frameworks (HOFs), , as a type of emerging crystalline framework formed by organic building blocks via intermolecular hydrogen bonds, possess both excellent liquid-phase self-assembly and flexible block designability, which offer an alternative to realize a novel porous organic lasing material . The great designability of HOFs permits the introduction of diverse organic luminescent chromophores into the building blocks, which could ensure a high optical gain in HOFs. , The flexible hydrogen bonds of HOFs allow for the modulation on the nucleation processes via controlling surrounding environments, , which is helpful to achieve different conformations of one gain building block, thus leading to substantial changes in luminescence. − Moreover, the self-assembly character enables HOFs to generate high-quality microcrystals with regular shapes, which offer efficient optical confinement. , Therefore, the HOFs with conformation-induced tunable gain regions may offer an effective approach for realizing wavelength-tunable lasing actions in porous organic systems. However, the corresponding investigations have been unexplored, which limit the development of HOF-based photonics.…”

Fluorinated Organic Porous Materials

“…In a very recent work, we have examined a fluorinated tetragonal precursor to PMCs based on the central tetraphenylene ethylene unit, which is a well-documented AIEgen. 67 This material shows switchable emission in the solid state, which can be toggled between green and blue by the removal and re-addition of the DMF solvent. Hisaki and coworkers have recently incorporated orthofluorine substituents into the structures of their porous hydrogen-bonded networks built on carboxylic acids.…”

Supramolecular Hydrogen Bonding Assembly from Non-Coplanar Aromatic Tetra-1H-Pyrazoles with Crystallization-Induced Emission (CIE)

“…Although the aromatic-rich linkers featuring multi-1 H-pyrazole motifs as fundamental building blocks are promising in the construction of supramolecular assemblies as hydrogen-bonded organic frameworks via hydrogen-bonding [N-H•••N] interaction [22][23][24], such HOFs based on the non-coplanar tetra-1 H-pyrazoles remain unexplored despite their interesting structures and optical properties [25]. We have prepared three tetra-1 Hpyrazolyl-substituted compounds named as 1-3 [H 4 TP-Be (1) H 4 TP-Py (2) H 4 TP-TPE (3), TP = tetrapyrazole Be = benzene Py = pyrene TPE = tetraphenylethylene] bearing four 1 H-pyrazole binding sites as flexible arms (Scheme 1a and SI) with dramatically different supramolecular self-assembly abilities from 1 H-pyrazole units and photoluminescence characteristics from benzene/pyrene/tetraphenylethylene cores [26].…”