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An iron(III)‐promoted radical fluoroalkylation of o‐alkenylaryl isocyanides has been developed using readily available perfluoroalkyl iodides as fluoroalkyl source. This cyclization reaction features broad substrate scope and provides a simple and efficient approach for regioselective construction of biologically important 2‐fluoroalkylated quinolines in 38–81 % yields. [ABSTRACT FROM AUTHOR]

For multiple resonance (MR) type thermally activated delayed fluorescence (TADF) emitters, electron cloud distributions of their π‐conjugated planes are crucial for determining their eventual performance. Currently, modulation attempts of MR‐TADF emitters are mainly inside the π‐conjugated planes. Possible out‐of‐plane interactions may also significantly impact the photophysical properties, but the exploration is quite limited. Here, a novel concept of using out‐of‐plane (e.g., π–π and lone pair‐π) interactions to introduce spatial perturbation (SPPT) to improve TADF performance is proposed. Two newly developed MR‐TADF emitters, namely, o‐BNPO and BNPO, which both consist of a popular MR framework, DtBuCzB, and diphenylphosphine oxide (DPPO), are compared in depth. In particular, for o‐BNPO, evident π–π interaction is observed between one side of the DtBuCzB π‐conjugated plane and a phenyl ring from DPPO, and lone pair‐π interaction with the oxygen atom from DPPO is noticed on the other side, resulting in significantly accelerated reverse intersystem crossing and better TADF without sacrificing narrowband emission features. Ultimately, in organic light‐emitting diodes with sensitizer‐free emitting layers, both emitters achieve similar narrowband emissions, while the o‐BNPO‐based device demonstrates a much higher external quantum efficiency of 36% and milder efficiency roll‐off. [ABSTRACT FROM AUTHOR]

Multiresonant thermally activated delayed fluorescence (MR-TADF) compounds are attractive for use in organic light-emitting diodes as they show narrowband emission, are bright, and can harvest both singlet and triplet excitons for the emission of light. Reflected in the paucity of examples of orange-to-red emitters, developing MR-TADF emitters that emit beyond the green remains an outstanding materials design challenge. In this work, we report one of the first carbonyl-based orange MR-TADF emitters, DDiKTa-A, which is based on the dimerization of the sky-blue emitting DiKTa through a central aniline bridge. DDiKTa-A emits at λPL of 562 nm and has high photoluminescence quantum yield of 92% in 2 wt% doped films in mCP. DDiKTa-A exhibits temperature dependent steady-state photoluminescence in 2-MeTHF, acting as an indirect indicator of the polarity of the medium. The OLEDs with DDiKTa-A showed an EQEmax of 20.3%, but with significant efficiency roll-off (EQE100 of 13.2%). The EQEmax was improved, and the efficiency roll-off mitigated by incorporating an assistant dopant, 4CzIPN, within the emissive layer of the device. The hyperfluorescence device showed an EQEmax of 24.3%, which decreased to 22.5 and 14.6% at 100 and 1000 cd m−2, respectively. [ABSTRACT FROM AUTHOR]

Background:Children with special health care needs (CSHCN) require long-term and ongoing rehabilitation interventions supporting their development. Telerehabilitation can provide continuous rehabilitation services for CSHCN. However, few studies have explored the intention of CSHCN and their caregivers to use telerehabilitation and its impact on them. Objective:The objective of this study was to identify factors that influence the intention to use telerehabilitation among CSHCN and their caregivers. Methods:This study was a cross-sectional study. Based on the unified theory of acceptance and use of technology, extended with additional predictors (trust and perceived risk [PR]), this study developed a research model and proposed 10 hypotheses. A structured questionnaire was distributed to 176 caregivers. Data were analyzed and research hypotheses were tested using partial least squares structural equation modeling to better understand the factors influencing the use of telerehabilitation. Results:A total of 164 valid questionnaires were collected. CSHCN and their caregivers were overall satisfied with this telerehabilitation medical service. The results of the structural model analysis indicated that social influence (SI), facilitating conditions (FC), and trust had significant effects on behavioral intention (BI) to use telerehabilitation, while the paths between performance expectancy (PE), effort expectancy (EE), and PR and BI were not significant. PE, EE, and SI had a significant effect on trust. Moreover, EE and SI had indirect effects on BI, with trust as the mediator. Conclusions:The results indicated that SI, FC, and trust are significant factors influencing CSHCN and their caregivers' use of telerehabilitation. Trust is also an important mediator for the intention and highly influenced by PE, EE, and SI. [ABSTRACT FROM AUTHOR]