Hexaphenylbenzene‐Based Deep Blue‐Emissive Metallacages as Donors for Light‐Harvesting Systems

Abstract

We herein report the preparation of a series of hexaphenylbenzene (HPB)-based deep blue-emissive metallacages via multicomponent coordination-driven self-assembly. These metallacages feature prismatic structures with HPB derivatives as the faces and tetracarboxylic ligands as the pillars, as evidenced by NMR, mass spectrometry and X-ray diffraction analysis. Light-harvesting systems were further constructed by employing the metallacages as the donor and a naphthalimide derivative (NAP) as the acceptor, owing to their good spectral overlap. The judiciously chosen metallacage serves as the antenna, providing the suitable energy to excite the non-emissive NAP, and thus resulting in bright emission for NAP in the solid state. This study provides a type of HPB-based multicomponent emissive metallacage and explores their applications as energy donors to light up non-emissive fluorophores in the solid state, which will advance the development of emissive metallacages as useful luminescent materials.

Morpholine-Functionalized Multicomponent Metallacage as a Vector for Lysosome-Targeted Cell Imaging

“…Peaks at m / z = 948.8333, 1448.8005, 1094.8049, 1155.8308, and 1294.4116 were observed, which corresponded to [ 4a –7OTf] 7+ , [ 4b –5OTf] 5+ , [ 4c –5OTf] 5+ , [ 4d –5OTf] 5+ , and [ 4e –5OTf] 5+ , respectively. All these results suggest the successful formation of metallacages 4a – 4e . ,, …”

Highly efficient Förster resonance energy transfer between an emissive tetraphenylethylene-based metal–organic cage and the encapsulated dye guest

“…Förster resonance energy transfer (FRET) is a classic energy transfer process between different chromophores that proceeds via nonradiative dipole–dipole coupling, which has received considerable attention on account of its various applications in photocatalysis, 6 biological imaging, 7 fluorescence probes, 8 and luminescent materials. 9 In addition to matching the spectral overlap between the donor emission and acceptor excitation, 10 effective FRET requires an appropriate distance and dipole orientation between the donor and acceptor. 11 To date, various challenges have been faced using the reported FRET systems linked by covalent bonds (such as porphyrin arrays and dendrimers), such as their time-consuming, multistep synthetic processes, as well as the possibility of emission changes resulting from covalent functionalization.…”

Hexaphenyltriphenylene‐Based Multicomponent Metallacages: Host–Guest Complexation for White‐Light Emission

“…For instance, the integration of fluorescent ligands into metallacages gives a series of emissive metallacages, rendering them valuable for applications such as sensors, bioimaging agents and light-emitting devices. [27][28][29][30][31][32][33] However, owing to the charge transfer between the organic ligands and metal ions (MLCT), the constructed metallacages suffer from poor luminescence in most cases. In order to address this issue, an efficient strategy is to introduce propeller-shaped fluorophores as the building blocks, because the metal-coordination bonds will restrict the molecular motions of propeller-shaped molecules, which would offset the fluorescence quenching caused by MLCT and offer bright emission for the metallacages.…”