Insights into Coordination and (Semi-)Rigidity in the Molecular Design of Bicyclic Heterocycle Frameworks

Macrocyclic compounds, exhibiting unique properties arising from their large-ring frameworks, have captivated the attention of organic chemists over the last few decades. These molecules serve specific functions across disciplines, including synthetic chemistry, materials science, and biology. Representative molecules in this category, including crown ethers, calix[n]arenes, and porphyrinoids composed of ether/phenol/pyrrole subunits, exhibit unparalleled structural and functional diversity. In contrast, macrocycles exploiting quinoline/quinazoline as key building blocks to construct specific macrocyclic architectures have received limited attention and are much less explored. In this Highlight Review, we summarize our recent advances in oligo-quinoline/quinazoline macrocycles. Emphasis is focused on synthetic strategies, structural features, and emerging applications in organometallic, supramolecular, and photophysical chemistry. We anticipate that these collective results will guide new molecular designs within the broader family of heterocycle-based macrocycles.