D–A–D Structured Bis-acylhydrazone Exhibiting Aggregation-Induced Emission, Mechanochromic Luminescence, and Al(III) Detection

Abstract

A readily accessible D-A-D triad molecule 1 was synthesized through acylhydrazone bond formation using carefully chosen building blocks. The molecule 1 exhibits emission through charge-coupled proton transfer and enhanced emission induced through aggregation and mechanochromic luminescence. Further, it detects Al(III) selectively among other cations in an efficient manner.

Mechanofluorochromic Luminescence, and Al3+Detection of an Aggregation-Induced Emission-Active Salicylaldehyde-Based Acylhydrazone Derivative

“…Generally, the AIE-active organic molecules bearing rotatable aryl moieties with intermolecular loose stacking and/or weak π-π interactions usually exhibit MFC behaviors. [8,16,19,43,[45][46] Based on the above empirical conclusions, the MFC properties of DHBH were investigated. As shown in Figure 2, the as-prepared solid emitted a cyan-blue light under 365 nm UV illuminations with a peak emission at ca.…”

Star-Shaped ESIPT-Active Mechanoresponsive Luminescent AIEgen and Its On–Off–On Emissive Response to Cu2+/S2–

“…Compound LH 3 shows a level-off tail in UV–vis absorption measurements (Figure S6) when water content was above 50% in the CH 3 CN/water mixture, further attesting the characteristic features of the aggregate formation. 13c,26 AIE characteristics of LH 3 in the CH 3 CN/water mixture can be easily visualized through the naked eye under a UV lamp as well as in daylight (Figure S7), which indicates the aggregate formation behavior of LH 3 in the CH 3 CN/water mixture (Figure 2C).…”

“…Due to the presence of a strong electron-donating group in the periphery of the system, it facilitates the electron transfer from the diethylamino group to hydrogen-bonded imine nitrogen and led to the ICT-coupled ESIPT in the excited state. 14,15,25,26…”

“…This observed behavior clearly indicates the formation of an organic nanoaggregate at 50% water content. 5a,13c,26 Formation of the nanoaggregate was further ascertained by dynamic light scattering (DLS), field emission scanning electron microscopy (FE-SEM) measurements, and quantum yield calculations (Table S2). Compound LH 3 shows a level-off tail in UV–vis absorption measurements (Figure S6) when water content was above 50% in the CH 3 CN/water mixture, further attesting the characteristic features of the aggregate formation.…”

Multifunctional rhodamine B appended ROMP derived fluorescent probe detects Al3+ and selectively labels lysosomes in live cells

“…In this respect, and due to the potential impact of Al 3+ on human health and the environment, it is of considerable importance to develop new fluorescent sensor probes. To date, most of the reported Al 3+ probes developed are based on small organic molecules [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] , carbon dots [26][27][28] , MOFs 7,29 , and transition metal complexes 30,31 . However, many of such systems suffer from achieving specificity either due to the interference of other transition metal ions 4,9,32,33 or weak coordination and strong hydration ability (enthalpies of hydration is − 4680 kJ/mol) character.…”