Search

The preparation of multifunctionalized luminophores with full‐color emission based on an identical core skeleton is a significative but challenging research topic. In this work, eight donor‐donor‐acceptor (D‐D‐A)‐type luminogens based on a central carbazole core bearing a C6 hydrocarbon chain were designed by using different kinds of donor and acceptor units on the left and right, and synthesized in good yields. These D‐D‐A carbazole derivatives display deep‐blue, sky‐blue, cyan, green, yellow‐green, yellow, orange and red fluorescence in the solid state, achieving full‐color emission covering the whole visible light range under UV light illumination. Notably, the dicyano‐functionalized triphenylamine‐containing carbazole derivative exhibits rare aggregation‐induced near‐infrared emission and red‐to‐near‐infrared mechano‐fluorochromism with high contrast beyond 100 nm. Furthermore, the red‐emissive luminogen can serve as a potential candidate for cell imaging and photodynamic therapy (PDT). This work not only provides reference for the construction of full‐color emissive systems but also opens a new avenue to the preparation of multifunctionalized luminophores capable of simultaneous application in near‐Infrared mechanical‐force sensors and PDT fields. [ABSTRACT FROM AUTHOR]

Six fluorescent dyes containing the same central benzothiadiazole skeleton were synthesized. Fluorogenic compounds 1 and 2 demonstrated typical aggregation-induced emission enhancement and aggregation-induced emission phenomena. These benzothiadiazole-modified dyes emitted different crystal-state fluorescence including green, yellow-green, yellowish brown, orange red and red colors, and these compounds displayed contrasting force-responsive fluorescence characteristics. More specifically, compound 1 exhibited red-shifted mechanofluorochromism behavior, and compounds 4 – 6 exhibited blue-shifted mechanofluorochromism phenomena, while compounds 2 and 3 showed no fluorescence change under mechanical stimulation. Among these benzothiadiazole derivatives, luminogens 1 and 6 presented mechanically triggered high-contrast bathochromic and hypsochromic fluorescence responses, respectively. Based on their various crystal fluorescence and force-sensitive emissive properties of fluorogenic molecules 1 – 6 , an interesting multilevel information encryption system was successfully constructed. Indeed, this study not only provided a valuable reference for the preparation of luminophores possessing rich mechanoluminochromic natures, but also extended ideas for the development of advanced information encryption systems. • Six benzothiadiazole derivatives were synthesized. • Compound 1 showed aggregation-induced emission enhancement feature. • Compound 2 showed aggregation-induced emission feature. • Solids 1 , 4 , 5 , and 6 displayed hypso- or bathochromic mechanofluorochromic behaviors. • A multilevel information encryption system was successfully constructed. [ABSTRACT FROM AUTHOR]

Front Cover: Full-Color Emissive D-D-A Carbazole Luminophores: Red-to-NIR Mechano-fluorochromism, Aggregation-Induced Near-Infrared Emission, and Application in Photodynamic Therapy (Chem. Eur. J. 11/2023) Keywords: aggregation-induced near-infrared emission; carbazoles; full-color emission; mechano-fluorochromism; photodynamic therapy EN aggregation-induced near-infrared emission carbazoles full-color emission mechano-fluorochromism photodynamic therapy 1 1 1 02/23/23 20230221 NES 230221 B Rectangular columns b of deep-blue, sky-blue, blue-green, green, yellow-green, yellow, orange and red suggest eight donor-donor-acceptor (D-D-A)-type carbazole derivatives that display full-color emission. Aggregation-induced near-infrared emission, carbazoles, full-color emission, mechano-fluorochromism, photodynamic therapy. [Extracted from the article]

[Display omitted] Mechanochromic luminophores that display luminescent changes upon exposure to external mechanical force have received considerable attention due to their promising applications in numerous fields including mechano-sensors and data recording. High brightness aggregative-state emission has great significance for achieving effective applications of mechanochromic luminogenic molecules, and luminophores with aggregation-induced emission effect are capable of exhibiting strong aggregative-state luminescence. In this review, we summarize the aggregation-induced emission-active tetraphenylethylene-functionalized compounds and complexes with mechanochromic luminescence characteristics, as well as discuss their mechanoluminochromic mechanisms. This review will provide a valuable reference for the potential opportunities and future challenges in this fascinating scientific field. [ABSTRACT FROM AUTHOR]

• We successfully developed a series of full-color emissive luminogens. • All these luminogens contain an identical central carbazole core. • Compounds Ⅱ and Ⅴ showed AIEE behavior. • Compounds Ⅲ and Ⅳ showed aggregation fluorescence change behavior. • Compounds Ⅴ and Ⅵ exhibited reversible mechanofluorochromic properties. The construction of multi-functionalized luminophores with full-color emission based on the same core skeleton is an appealing yet significantly challenging task. In this work, we rationally designed and facilely constructed a series of donor-donor-acceptor (D-D-A) based luminogens by representative Suzuki-Miyaura cross-coupling reaction. Using electron-donating carbazole with hexyl chain as basic core structure, a series of donor-donor-acceptor (D-D-A) typed luminogens with different donor and acceptor units were designed and synthesized. Some compounds showed AIEE or aggregate fluorescence change behaviors due to TICT and RIM. Among them, these compounds displayed diverse mechanofluorochromic characteristics, including reversible or irreversible, red-shifted or blue-shifted mechanofluorochromisms. This provided new ideas for the development of multifunctional organic light-emitting molecules. [Display omitted] [ABSTRACT FROM AUTHOR]