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A practical and efficient approach for the synthesis of fluorescent 2,3-naphthalimide derivatives has been developed from readily available starting materials via an intramolecular didehydro-Diels-Alder reaction, which proceeded well under room temperature, exhibiting a wide substrate scope and good functional group tolerance. The practicability of this methodology has been verified by one-step synthesis of the environmentally sensitive fluorophore 6-DMN on a gram scale with a shorter time, fewer steps and less waste disposal, and without the utilization of toxic transition metals. The present experimental and computational studies support the crucial role of the propiolimide moiety in the transformation.

We managed to integrate the features of aggregation-induced emission (AIE) and thermally activated delayed fluorescence (TADF), by introducing a fluorine atom into the quinoxaline system for highly efficient fluorescent OLEDs. With a purposive design and well-controlled synthesis, two novel AIE-TADF compounds were demonstrated and characterized. Monofluoro-substituted SFDBQPXZ exhibited high efficiencies in a doped OLED with a maximum EQE of 23.5%, a maximum current efficiency (CE) of 78.3 cd A−1 and a maximum power efficiency (PE) of 91.1 lm W−1. Noteworthily, by employing SFDBQPXZ as an orange emitter in a non-doped device, we have realized a considerably high EQE over 10%. The high efficiency and low roll-off in the doped or non-doped devices make our strategy promising and meaningful for OLED applications.

A new orange-red thermally activated delayed fluorescence (TADF) emitter is designed and synthesized by incorporating a fluorine-substituted quinoxaline as an electron-acceptor and a phenoxazine as an electron-donor. The rational molecular design enables small singlet–triplet energy splitting (ΔEST) and high fluorescence radiative rate (kSr) for long-wavelength TADF emitters. The organic light emitting diodes (OLEDs) employing the new TADF emitter achieve maximum external quantum efficiencies (EQEs) of 13.9% and 9.0% for the vacuum- and solution-processed OLEDs, respectively.

A one-pot reaction of nitroalkenes and enones was developed for the preparation of nitro-vinyl-substituted cyclohexanes, which could be simply converted into poly-N-heterocycles.