Heteroatom doping in carbon macrocycles for advanced synthesis and applications

Macrocycles have garnered significant research interest due to their tunable structures, unique physicochemical properties, and broad range of applications in areas such as aggregation-induced emission (AIE), molecular recognition, bioimaging, and photocatalysis. While conventional carbon-rich macrocycles depend mainly on ring-size adjustments for property modulation, the incorporation of heteroatoms (N, O, and S) allows precise control over electronic structure, band gap, and functionality. This review summarizes recent advances (2020-2025) in the synthesis and applications of heteroatom-doped (N-, O-, S-, N,O-, and N,S-doped) macrocycles. It covers metal-catalyzed (Pd, Ni, Pt, Cu, Ti, Sn, and Fe) and metal-free (acidic/basic) strategies, post-synthetic modifications, and emerging applications in host-guest systems, sensors, OLEDs, OFETs, OPVs, and (photo)catalysis, aiming to advance the field and serve as a reference for cross-disciplinary researchers.