Tetraphenylethene-based macrocycles with dual-ring topology: synthesis, structures, and applications

In the past few decades, macrocycles with different structures and functions have played a crucial role in supramolecular chemistry. Due to its symmetrical structure, simple synthesis process, good stability, and easily adaptable reaction sites, tetraphenylethylene (TPE) has gained recognition as a universal basic block in macrocyclic chemistry, supramolecular aggregate materials, etc. A series of eight-shaped double macrocycles can be formed by connecting the benzene rings of TPE in pairs. Compared with monomacrocycles, the unique structures of bismacrocycles lead to their specific recognition and assembly properties, and also a wide range of applications, including biological imaging, fluorescent probes, and optoelectronic devices. This review focuses on the eight-shaped double-ring structure of TPE, summarizing the research on neutral molecular structures, ionic molecular structures, and metal molecular structures, and future research directions.