Highly emissive platinum(II) metallacages

Abstract

Light-emitting materials, especially those with tunable wavelengths, attract considerable attention for applications in optoelectronic devices, fluorescent probes, sensors and so on. Many species evaluated for these purposes either emit as a dilute solution or on aggregation, with the former often self-quenching at high concentrations, and the latter falling dark when aggregation is disrupted. Here we preserve emissive behaviour at both low- and high-concentration regimes for two discrete supramolecular coordination complexes (SCCs). These tetragonal prismatic SCCs are self-assembled on mixing a metal acceptor, Pt(PEt3)2(OSO2CF3)2, with two organic donors, a pyridyl-decorated tetraphenylethylene and one of two benzene dicarboxylate species. The rigid organization of these fluorescence-active ligands imparts an emissive behaviour to dilute solutions of the resulting assemblies. Furthermore, on aggregation the prisms exhibit variable-wavelength visible-light emission, including rare white-light emission in tetrahydrofuran. The favourable photophysical properties and solvent-dependent aggregation behaviour provide a means to tune emission wavelengths.

Tetraphenylethene-based highly emissive metallacage as a component of theranostic supramolecular nanoparticles

“…Downfield shifts were also observed for the resonances corresponding to the protons on dicarboxylate ligand 1 due to the loss of electron density that occurs on coordination (SI Appendix, Fig. S9B) (14). On formation of the tetragonal prism, the resonances in the With the metallacage in hand, its photophysical properties were compared with those of 3.…”

“…1) that occurs when two donor building blocks (1 and 3) are mixed with cis-(PEt 3 ) 2 Pt(OTf) 2 (2). When combined in a 4:2:8 ratio, precursors 1, 3, and 2 act as the edges, faces, and vertices of the metallacage (4), respectively, under the principles of edge-directed and face-directed directional bonding (12)(13)(14)(15)(16). The core of 3 is a TPE moiety whose intramolecular aromatic ring rotation becomes restricted on coordination.…”

Networked Cages for Enhanced CO2 Capture and Sensing

“…[[qv: 12a]] X‐ray crystallographic analysis and nitrogen sorption experiments both confirmed the presence of micropores with an average size of 5.8 Å, which is comparable to the size of CO 2 (3.3 Å). From these results, we predicted that if CO 2 molecules are trapped in the intrinsic cavity of OMCs, the rotation and vibration of phenyl rings in tetraphenylethylene (TPE) units may be affected resulting in fluorescence enhancement because of the aggregation‐induced emission (AIE) effect,13, 14, 15, 16 and may offer an alternative approach to sense CO 2 . Herein, we synthesized a cage‐based polymeric framework (pTOC) by nickel (0)‐catalyzed Yamamoto‐type Ullmann crosscoupling reaction ( Scheme 1 )17 from TPE‐based oxacalixarene cage (TOC) having polymerizable groups.…”

Fluorescent metallacycle-cored polymers via covalent linkage and their use as contrast agents for cell imaging

“…Due to the directionality of metal−ligand bonds and their moderate bond energies, the structures of SCCs can be finely tuned. So far, various SCCs with different geometries, such as 2D metallacycles (25)(26)(27)(28) and 3D metallacages (29)(30)(31)(32), were successfully prepared by the self-assembly of carefully selected metal acceptors and organic donors. Moreover, metal−ligand interactions show good tolerance of other noncovalent interactions such as hydrogen bonding and host−guest interactions, which were used to construct highly advanced functional supramolecular entities, such as mechanically interlocked molecules (33)(34)(35) and supramolecular polymers (36)(37)(38), via orthogonal self-assembly.…”