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The development of efficient deep-blue emitters with thermally activated delayed fluorescence (TADF) properties is a highly significant but challenging task in the field of organic light-emitting diode (OLED) applications. Herein, we report the design and synthesis of two new 4,10-dimethyl-6H,12H-5,11-methanodibenzo[<i>b,f</i>][1,5]diazocine (<b>TB</b>)-derived TADF emitters, <b>TB-BP-DMAC</b> and <b>TB-DMAC</b>, which feature distinct benzophenone (<b>BP</b>)-derived acceptors but share the same dimethylacridin (<b>DMAC</b>) donors. Our comparative study reveals that the amide acceptor in <b>TB-DMAC</b> exhibits a significantly weaker electron-withdrawing ability in comparison to that of the typical benzophenone acceptor employed in <b>TB-BP-DMAC</b>. This disparity not only causes a noticeable blue shift in the emission from green to deep blue but also enhances the emission efficiency and the reverse intersystem crossing (RISC) process. As a result, <b>TB-DMAC</b> emits efficient deep-blue delay fluorescence with a photoluminescence quantum yield (PLQY) of 50.4% and a short lifetime of 2.28 μs in doped film. The doped and non-doped OLEDs based on <b>TB-DMAC</b> display efficient deep-blue electroluminescence with spectral peaks at 449 and 453 nm and maximum external quantum efficiencies (EQEs) of 6.1% and 5.7%, respectively. These findings indicate that substituted amide acceptors are a viable option for the design of high-performance deep-blue TADF materials.