Chiral aggregation-induced emission luminogens (AIEgens) have great potential in circularly polarized luminescence (CPL). Owing to their high emission quantum yield in the solid state, luminogens with aggregation-induced emission (AIE) characteristics are promising candidates for chiral emitting materials. However, rapid ring flipping in propeller-shaped AIEgens tends to lead to racemization in solution.
Yi Liu, Shenzhen University, China, and colleagues have synthesized a series of chiral, macrocyclic AIEgens decorated with tunable emission colors (pictured below). The team used intramolecular McMurry couplings to construct the chiral AIE-active units. The “propeller” chirality of tetraphenylethene (TPE) moiety was pre-determined by the BINOL unit via chirality transfer along the cyclic backbone.
The researchers found that the synthesized chiral AIEgens all displayed bright solid-state emission and mirror-imaged CPL across the visible spectrum. These AIEgens maintained high solid-state emission quantum yields and produced CPL emission from blue to red when in nano-aggregates, liquid crystal matrices, and polymer films. In addition to donor-acceptor engineering, different polymer matrices could also be used to tune the emission of some of the AIEgens. Overall, the work provides an approach to constructing full-spectrum solid-state CPL materials.
- Full‐color‐tunable chiral aggregation‐induced emission fluorophores with tailored propeller chirality and their circularly polarized luminescence,
Yifan Li, Junhao Liang, Shiwei Fu, Haoxin Huang, Sheng Liu, Lei Wang, Yi Liu,
Aggregate 2024.
https://doi.org/10.1002/agt2.613
