Bridged chemistry of macrocyclic arenes: from sp ³ -carbon bridges to π-conjugation and heteroatom bridging

Macrocyclic arenes are a class of host molecules featuring precisely adjustable cavities and abundant recognition sites, which facilitate rich host-guest interactions. Their bridging structures-such as methylene groups, conjugated units, and heteroatoms (<i>e.g.</i>, O, S, N, and Si)-can be rationally designed to fine-tune cavity microenvironments, conformational dynamics, and optoelectronic properties. These capabilities make them key building blocks for constructing molecular containers, sensors, and smart supramolecular assemblies. In recent years, macrocyclic arenes constructed from various aromatic building units and bridging groups have gained widespread attention due to their highly symmetrical rigid frameworks, tunable electronic properties, and rich host-guest chemical behaviors. This article systematically reviews the research progress in this class of macrocyclic arenes, focusing on the regulatory effects of different bridging structures on their cavity sizes, conformational features, and optoelectronic properties. It summarizes the latest developments in synthetic strategies such as one-pot methods, fragment coupling, and post-synthetic modifications and discusses their applications in molecular recognition, pollutant adsorption, optoelectronic material construction, and stimuli-responsive systems. Finally, we look ahead to the challenges and development prospects facing macrocyclic arenes in design synthesis and future applications, aiming to provide useful references and insights for research in this field.