Influence of Steric Effects on the Emission Behavior of Pyrene-Based Blue Luminogens

Xie, Zhixin; Liu, Wei; Liu, Yiwei; Song, Xinyi; Zheng, Heng; Su, Xiang; Redshaw, Carl; Feng, Xing

Abstract

Pyrene-based derivatives have been widely deployed in organic luminescent materials because of their bright fluorescence, high charge carrier mobility, and facile modification. Nevertheless, the fluorescence output of conventional pyrenes is prone to quenching upon aggregation due to extensive intermolecular π-π stacking interactions. To address this issue, a set of new Y-shaped pyrene-containing luminogens are synthesized from a new bromopyrene chemical precursor, 2-hydroxyl-7-tert-butyl-1,3-bromopyrene, where the bromo and hydroxyl groups at the pyrene core can be readily modified to obtain the target products and provide great flexibility in tuning the photophysical performances. When the hydroxy group at the 2-position of pyrene was replaced by a benzyl group, the steric hindrance of the benzyl group not only efficiently inhibits the detrimental intermolecular π-π stacking interactions but also rigidifies the molecular conformation, resulting in a narrow-band blue emission. Moreover, the TPE-containing compounds 2c and 3c possessed characteristic aggregation-induced emission (AIE) properties with fluorescence quantum yields of up to 66% and 38% in the solid state, respectively. Thus, this article has methodically investigated the factors influencing the optical behavior, such as intermolecular interactions, and the steric effects of the substituent group, thereby opening up the potential to develop narrow-band pyrene-based blue emitters for OLED device applications.

Citation

Xie, Z., Liu, W., Liu, Y., Song, X., Zheng, H., Su, X., Redshaw, C., & Feng, X. (2024). Influence of Steric Effects on the Emission Behavior of Pyrene-Based Blue Luminogens. Journal of Organic Chemistry, 89(3), 1681-1691. https://doi.org/10.1021/acs.joc.3c02372

• Journal Article Type: Article
• Acceptance Date: Dec 28, 2023
• Online Publication Date: Jan 11, 2024
• Publication Date: Feb 2, 2024
• Deposit Date: Feb 3, 2024
• Publicly Available Date: Jan 12, 2025
• Journal: Journal of Organic Chemistry
• Print ISSN: 0022-3263
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 89
• Issue: 3
• Pages: 1681-1691
• DOI: https://doi.org/10.1021/acs.joc.3c02372
• Keywords: Pyrene; Blue emitter; Aggregation-induced emission; Steric effect
• Public URL: https://hull-repository.worktribe.com/output/4526391