Hierarchical Self-Assembly of a Pyrene-Based Discrete Organoplatinum(II) Double-Metallacycle with Triflate Anions via Hydrogen Bonding and Its Tunable Fluorescence Emission

Abstract

Hierarchical self-assembly of discrete organo­platinum­(II) metalla­cycles has attracted considerable attention. However, the exact assembly mechanism involving non-covalent interactions has limited the formation and application of self-assembly due to the dynamics of platinum metalla­cycles. Herein, we report the hierarchical self-assembly of a pyrene-based discrete organo­platinum­(II) double-metalla­cycle that takes advantage of hetero­ligation-coordination-driven self-assembly and triflate anions’ hydrogen bonding, which is extended into a 3-D supra­molecular framework by the hydrogen-bonding interactions involving triflate anions. Furthermore, the assembled system displays tunable fluorescence emission and enhanced solid emission. The studies herein disclosed pave the way to prepare platinum­(II) metalla­cycle-based supra­molecular functional materials.

Highly Emissive Perylene Diimide-Based Metallacages and Their Host–Guest Chemistry for Information Encryption

“…Stang and coworkers tackled this problem by introduction of tetraphenylethene (TPE) derivatives as the fluorophores to prepare a series of emissive metallacages. [20][21][22][23][24][25] However, these metallacages are unable to bind organic guests, perhaps due to the twist configuration of TPE and the metallacycle-metallacage structural transition [26][27] in solution. The exploration of the host-guest chemistry for emissive metallacages will not only offer a pathway to finely tune the emission of the complexes but also promote their use for photocatalytic reactions in confined spaces.…”

“…These values are among the highest binding constants for emissive metallacage-based host-guest interactions. [20][21][22][23][24][25][26][27][28][29][30][31][32] The binding affinity of metallacages towards PAHs is attributed to the π-π stacking interactions between the electrondeficient PDI and the electron-rich PAHs. Because of slightly different sizes and shapes of the three PAHs, it is likely that they will have different binding modes and energies with PDI-based metallacages, which gives them different binding affinities with the two metallacages.…”

Metallacycles, metallacages, and their aggregate/optical behavior

“…The dark blue emission is maintained as the hexane ratio increases to 90%. [29] AIEactive 9,10-di(4-pyridylvinyl)anthracene (DPA) was locked into M7/M8, and M7 showed pale orange fluorescence with a peak at 576 nm in pure acetone, with a slight blueshift of ca. 6 nm as the hexane content increased to 50%.…”

“…The chemical structure of M39 and the corresponding emission of M39 in acetone/hexane mixtures with different fractions of hexane [29] ; (B) M7 and M8 in acetone/hexane mixtures [52b] ; (C) emissions of M13 and M14 in DCM/hexane mixtures with different fractions of hexane [53a] ; (D) the interactions between M9/10 and perylene [52c] ; (E) white-light emission produced by mixing M40 and G1 [56] ; and (F) interaction between M41 and G2. [17a] Copyright 2017, 2020 American Chemical Society.…”

“…[25] To improve the photophysical properties, [26] various lumiphores have been used as functional units to construct coordination interactionbased suprastructures [27] with tunable emissions. To date, anthracene, [28] pyrene, [29] phenanthrene, [30] porphyrin, [31] and tetra-(4-pyridylphenyl)ethylene (TPPE) [32] have been used as skeletal or functional groups (Scheme 1), leading to the formation of MOCs with emission wavelengths ranging from blue to green to red and near-infrared regions. Normally, after CDSA, the resultant MOCs show a distinct redshift and lower quantum yield (compared to the precursor) in both the absorption and fluorescence spectra due to metal-ligand charge transfer (MLCT).…”