Review: Comparative Analysis of Structures, Functions, Coordination and Applications of N-Fused and N-Confused Porphyrins
DOI:
https://doi.org/10.55544/sjmars.5.4.5Keywords:
Porphyrins, N-Confused Porphyrin, N-Fused Porphyrin, PorphyrinoidsAbstract
Porphyrins and their structural analogues occupy a central position in bioinorganic chemistry, materials science, and catalysis, largely because of their adaptable macrocyclic frameworks. Two structurally modified variants — N-fused porphyrins (NFPs) and N-confused porphyrins (NCPs) — have attracted sustained interest as aza-modified macrocycles with distinct electronic, coordinative, and structural profiles. Although both classes involve nitrogen-based modifications to the classical tetrapyrrolic core, the nature and consequences of those modifications differ considerably between them.
In NFPs, a pyrrole ring is fused to the meso nitrogen, yielding enhanced aromatic conjugation and a more rigid framework. NCPs, by contrast, arise from an inversion at the β-position of one pyrrole unit, which repositions a nitrogen atom to the periphery of the macrocycle and generates an unusual coordination pocket. This review systematically compares the structural and electronic characteristics of NFPs and NCPs, surveys their metal coordination behaviors, and examines their functional applications.
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