Blue Phosphorescence and Hyperluminescence Generated from Imidazo[4,5-b]pyridin-2-ylidene-Based Iridium(III) Phosphors.

Four isomeric, homoleptic iridium(III) metal complexes bearing 5-(trifluoromethyl)imidazo[4,5-b]pyridin-2-ylidene and 6-(trifluoromethyl)imidazo[4,5-b]pyridin-2-ylidene-based cyclometalating chelates are successfully synthesized. The meridional isomers can be converted to facial isomers through acid induced isomerization. The m-isomers display a relatively broadened and red-shifted emission, while f-isomers exhibit narrowed blue emission band, together with higher photoluminescent quantum yields and reduced radiative lifetime relative to the mer-counterparts.

Asymmetrical-Dendronized TADF Emitters for Efficient Non-doped Solution-Processed OLEDs by Eliminating Degenerate Excited States and Creating Solely Thermal Equilibrium Routes.

The mechanism of thermally activated delayed fluorescence (TADF) in dendrimers is not clear. We report that fully-conjugated or fully-nonconjugated structures cause unwanted degenerate excited states due to multiple identical dendrons, which limit their TADF efficiency. We have synthesized asymmetrical "half-dendronized" and "half-dendronized-half-encapsulated" emitters.

Development of a UPLC-MS/MS method for determination of a dual EZH1/2 inhibitor UNC1999 in rat plasma.

We aimed to establish and validate a simple and sensitive UPLC-MS/MS method for the determination of UNC1999, a dual inhibitor against EZH1 and EZH2 in plasma samples. UNC1999 in rat plasma was processed with protein precipitation method and then separated on a C column and detected under positive ionization mode. The method presented good linearity over the range of 1.

Photoluminescent Behaviors of Thermally Activated Delayed Fluorescence Polymeric Emitters in Nanofibers.

Anisotropic 1D nanostructures with high surface-area-to-volume ratio display the enhanced optoelectronic properties of light-emitting compounds compared to bulk or 2D systems. To study the effect of nanometer-constrained space on photoluminescent behavior of thermally activated delayed fluorescence (TADF) polymeric emitters, electrospinning technique is used to produce nanofibers of TADF emitters. Herein, two TADF polymer (P1 and P3) nanofibers with 90% polyacrylonitrile (PAN) are fabricated and their photophysical properties are studied and compared with their spin-coated film counterparts.

Synthesis and Cyclization-Induced Charge Transfer of Rectangular Bisterthiophenesiloxanes.

Cyclization-modified terthiophene displays the change of emission behavior from locally excited (LE) to the intramolecular charge transfer (ICT) state. The rectangular bisterthiophenesiloxanes (DSiTh) was successfully prepared by π-π-stacking-aided hydrogen-bonding interactions. Cyclization-induced ICT in DSiTh could be observed, which was confirmed by absorption spectra, fluorescence spectra, and quantum chemistry analysis.

Thermally Activated Delayed Fluorescence Pendant Copolymers with Electron- and Hole-Transporting Spacers.

To study the effect of hole- and electron-transporting spacers in copolymers on the thermally activated delayed fluorescence (TADF) properties and device efficiency of copolymers, two series of copolymers PCzPT-x and POPT-x have been designed and synthesized successfully. In these copolymers, 2-(10H-phenothiazin-10-yl)dibenzothiophene-S,S-dioxide units give green-yellow TADF, while hole-transporting 9-(4-vinylphenyl)-9H-carbazole units or electron-transporting diphenyl(4-vinylphenyl)phosphine oxide act as spacers or hosts. Their thermal, electrochemical, photophysical, and electroluminescent properties and theoretical calculations are systematically investigated to illustrate the relationships between molecular structures and photophysical properties.

Pyridylpyrazole N^N ligands combined with sulfonyl-functionalised cyclometalating ligands for blue-emitting iridium(iii) complexes and solution-processable PhOLEDs.

A series of blue iridium(iii) complexes (12-15) comprising sulfonyl-functionalised phenylpyridyl cyclometalating ligands and pyridylpyrazole N^N ligands are reported, with an X-ray crystal structure obtained for 12. The complexes are highly emissive with photoluminescence quantum yields of 0.52-0.