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Disclosed herein is a RhCl3‐catalyzed peri‐selective C−H/C−H oxidative homo‐coupling of 1‐substituted naphthalenes, which provides a highly efficient and streamlined approach to chalcogen‐embedded anthanthrenes from readily available starting materials. Introducing O, S, and Se into the anthanthrene skeleton leads to gradually increased π–π stacking distances but significantly enhanced π–π overlaps with the growth of the hetero‐atom radius. Moderate π–π distance, overlap area, and intermolecular S−S interactions endow S‐embedded anthanthrene (PTT) with excellent 2D charge‐transport properties. Moreover, the transformation of p‐type to n‐type S‐embedded anthanthrenes is realized for the first time via the S‐atom oxidation from PTT to PTT‐O4. In organic field‐effect transistor devices, PTT derivatives exhibit hole transport with mobilities up to 1.1 cm2 V−1 s−1, while PTT‐O4 shows electron transport with a mobility of 0.022 cm2 V−1 s−1. [ABSTRACT FROM AUTHOR]

The academically widely used electron‐transporting materials (ETMs) typically suffer from low glass transition temperatures (Tg) that could lead to poor device stability. Considering practical applications, we herein put forward a "3D molecular interaction architecture" strategy to design high‐performance ETMs. As a proof‐of‐concept, a type of structurally nontraditional ETMs with the benzo[c]cinnoline (BZC) skeleton have been proposed and synthesized by the C−H/C−H homo‐coupling of N‐acylaniline as the key step. 2,9‐diphenylbenzo[c]cinnoline (DPBZC) exhibits strong intermolecular interactions that feature a 3D architecture, which boosts Tg to exceedingly high 218 °C with a fast electron mobility (μe) of 6.4×10−4 cm2 V−1 s−1. DPBZC‐based fluorescent organic light‐emitting diodes show outstanding electroluminescent performances with an external quantum efficiency of 20.1 % and a power efficiency as high as 70.6 lm W−1, which are superior to those of the devices with the commonly used ETMs. [ABSTRACT FROM AUTHOR]

Benzophenone skeletons containing a carbonyl unit (O=C) have been widely used as electron acceptors in the thermally activated delayed fluorescence (TADF) materials. Herein, we present a novel molecular design concept for TADF materials by transitioning from a carbonyl to an amide (O=C-N) skeleton as the acceptor. The amide unit, compared to its carbonyl counterpart, offers a more stable electronic configuration. Leveraging this insight, we have developed a series of high-performance TADF molecules based on benzoyl carbazole and carbazoline acceptors. These molecules exhibit exceptionally small singlet-triplet energy gaps and pronounced aggregation-enhanced emission properties, achieving photoluminescence quantum yields in neat films as high as 99%. Consequently, these materials serve as efficient emitters in non-doped organic light-eimtting diodes (OLEDs), reaching a maximum quantum efficiency (EQEmax) of up to 26.0%, significantly higher than the 17.0% obtained with benzophenone acceptor-based TADF molecules. Additionally, they have been used as TADF hosts in narrowband red fluorescent OLEDs, setting a record-high EQEmax of 22.4%., (© 2024 Wiley‐VCH GmbH.)

Narrowband organic light-emitting diodes (OLEDs) are receiving significant attention and have demonstrated impressive performance in blue and green OLEDs. However, developing high-performance narrowband red OLEDs remains a highly desired yet challenging task. Herein, we have developed narrowband red fluorescent emitters by utilizing a boron-dipyrromethene (BODIPY) skeleton in combination with a methyl-shield strategy. These emitters exhibit small full-width at half-maxima (FWHM) ranging from 21 nm (0.068 eV) to 25 nm (0.081 eV) and high photoluminescence quantum yields (Φ PL ) ranging from 88.5 % to 99.0 % in toluene solution. Using BODIPY-based luminescent materials as emitters, high-performance narrowband red OLEDs have been assembled with external quantum efficiency as high as 18.3 % at 623 nm and 21.1 % at 604 nm. This work represents, to our knowledge, the first successful case of achieving NTSC pure-red OLEDs with the Commission Internationale de l'Éclairage (CIE) coordinates of [0.67, 0.33] based on conventional fluorescent emitters., (© 2023 Wiley-VCH GmbH.)

Disclosed herein is a RhCl 3 -catalyzed peri-selective C-H/C-H oxidative homo-coupling of 1-substituted naphthalenes, which provides a highly efficient and streamlined approach to chalcogen-embedded anthanthrenes from readily available starting materials. Introducing O, S, and Se into the anthanthrene skeleton leads to gradually increased π-π stacking distances but significantly enhanced π-π overlaps with the growth of the hetero-atom radius. Moderate π-π distance, overlap area, and intermolecular S-S interactions endow S-embedded anthanthrene (PTT) with excellent 2D charge-transport properties. Moreover, the transformation of p-type to n-type S-embedded anthanthrenes is realized for the first time via the S-atom oxidation from PTT to PTT-O4. In organic field-effect transistor devices, PTT derivatives exhibit hole transport with mobilities up to 1.1 cm 2  V -1  s -1 , while PTT-O4 shows electron transport with a mobility of 0.022 cm 2  V -1  s -1 ., (© 2022 Wiley-VCH GmbH.)

The synthesis of efficient porphyrin-based photosensitizers with intense near-infrared (NIR) absorption is in high demand for photodynamic therapy (PDT) but remains a challenging task. Herein we show the construction of a type of isoquinoline-fused porphyrins 3 and 4 with an impressive NIR-absorbing capacity. In light of the extraordinary singlet oxygen generation capabilities of 3 upon NIR irradiation, the representative nanoparticles ( 3a-NPs ) assembled show excellent tumoricidal behavior with good biocompatibility in the phototherapeutic window (650-850 nm).