AIEgens Based on Anion‐π⁺ Interactions: Design, Synthesis, Photophysical Properties, and Their Applications in Material Science and Biology

Abstract

The design of novel aggregation‐induced emission luminogens (AIEgens), has generally been facilitated by disrupting the possibility of π‐π stacking. The recent literature describes a novel strategy to design AIEgens by introducing anion‐π+ interactions to prevent the detrimental π‐π stacking. This new strategy provides access to intrinsically charged AIEgens whose photophysical properties can be tuned either by incorporating different substituents on the π‐molecular scaffold to modulate the acidity for tuning the interaction energy between a π‐acceptor and counter‐anions. This concept article provides a brief overview of the field, focusing on the synthesis of AIEgens, their photophysical properties, crystallography studies and their applications in live cell fluorescence imaging.

Gold-catalyzed multicomponent reactions

“…10 Taken together, the published reviews are discrete and provide the impression that the field of gold catalysis has limited applications in the development of MCRs. Based on our continuing interest in the field of gold catalysis 11 and inspired by our recent work on gold-catalyzed MCRs, 12 we endeavoured to scrutinize all the available literature reports carefully. The literature survey revealed that there exist numerous gold-catalyzed MCRs with interesting reactivity patterns.…”

Constructing anion–π interactions in cationic iridium(iii) complexes to achieve aggregation-induced emission properties

“…37 Recent progress has been summarized in the reviews. 38,39 So far, studies of AIEgens based on anion-π interactions have mainly focused on fluorescent small molecules, 31 whereas research into phosphorescent materials has been rarely reported. Cationic iridium(III) complexes are well known as efficient triplet state luminescent materials with unique photophysical properties, including relatively short excitedstate lifetimes, excellent photo-and thermal stabilities, tunable emission properties, etc.…”

Anion−π Interaction in a Diketopyrrolopyrrole Derivative

“…Non-covalent interactions, such as hydrogen-bonding, π–π, and electron donor–acceptor interactions, play crucial roles in molecular self-assembly. − Among these non-covalent interactions, anion−π interactions have aroused great interest lately. − In a broad sense, anion−π interactions are interactions between anions and electron-deficient aromatic rings. , Not only new sensing methods but also tools for modulating molecular arrangement to produce desired optoelectronic character have been developed. Its applications have also been extended to the catalytic field.…”