A mechanochromic cyclemetalated cationic Ir(iii) complex with AIE activity by strategic modification of ligands

Abstract

Two new aggregation-induced emission (AIE)-active cyclemetalated cationic Ir(III) complexes have been rationally designed and synthesized by introducing O-H substituents into the Schiff base ligands. π-Hydrogen bonding is successfully exploited for...

Recent Advances in Mechanochromism of Metal-Organic Compounds

“…Under mechanical stimulation, the change of interactions lead to the change of stacking modes, resulting in the mechanochromism. Pei and Zhao' group prepared a series of cationic Ir(III) complexes with significant mechanochromic luminescence (Pei et al, 2020;Zhao et al, 2021). For the first time, the hydroxyl substituents were introduced into Ir mechanochromism.…”

“…Although the current research on mechanochromic metal-organic compounds is limited, such mechanochromic materials are still attractive and are expected to exhibit more interesting phenomena due to the metalophilic interactions existed in metal complexes. These mechanochromic phenomenons are thought to result from the crystalline-to-amorphous (CA) phase transformation, single-crystal-to-single-crystal (SCSC) phase transformation or triplet excited states transformation caused by the intermolecular conformational folding or twisting, as well as changes in intermolecular π-π, metalophilic or hydrogen-bonding interactions (Seki et al, 2013;Ito et al, 2013;Seki et al, 2015;Jin et al, 2017;Jin et al, 2018;Li et al, 2019;Pei et al, 2020;Xie et al, 2020). Indeed, an explicit mechanism has not been investigated yet because of the difficulty in characterizing the amorphous phase.…”

Ir(III) Complexes with AIE Characteristics for Biological Applications

“…In particular, AIEgens have unique aggregation-enhanced theranostics (AET) properties, referring to the advantages of enhancements in ROS generation, nonlinear optical effects under aggregation-induced effects [ 21 , 22 ]. On the other hand, many cases of Ir(III) complexes with AIE properties have been reported to date [ 23 , 24 , 25 , 26 ] and the following design strategies are generally recommended: (i) introducing active units with AIE properties into Ir(III) complexes and (ii) restricting intramolecular motion of flexible rotating units (such as imine bonds of Schiff bases) through coordination with the central metal iridium. Ir(III) complexes are potential phosphorescent molecules for the construction of AIE materials via strategic modification of ligands [ 27 ].…”

Multistimuli-responsive materials based on a zinc(ii) complex with high-contrast and multicolor switching

“…[31][32][33][34] Although some research studies on the stimulus-responsive properties of AIE/AIEE compounds have been reported, most of them focus on a single-stimulus response. [35][36][37] To broaden the scope of practical applications, we need to design multi-stimuliresponsive materials with multicolor and high-contrast, and deeply explore the relationship between their structure and properties.…”