Video Experimental Relacionado

Updated: Jan 8, 2026

Using Cyclic Voltammetry, UV-Vis-NIR, and EPR Spectroelectrochemistry to Analyze Organic Compounds

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Impacto del reemplazo de fenotiazina por fenoxazina en marcos de hexafirina en propiedades estructurales,

Neha Tripathi¹, Mangalampalli Ravikanth¹

¹Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India. ravikanth@chem.iitb.ac.in.

Organic & biomolecular chemistry

|December 24, 2025

Abstract:

Three phenoxazine-embedded hexaphyrins were synthesized from commercially available phenoxazine in a few simple steps and compared with our previously reported phenothiazine-embedded hexaphyrins. A striking structural distinction was observed between these two series. The phenoxazine-embedded hexaphyrins showed a more planar and symmetric structure, where the oxygen atom of phenoxazine faces outward and the nitrogen atom points inward toward the macrocyclic core. In contrast, the phenothiazine-embedded hexaphyrins were more distorted, with the sulfur atom facing inward and the nitrogen atom outward. Thus, replacing phenothiazine with phenoxazine caused a "flip" of the heterocyclic unit and changed the overall electronic structure of the macrocycle. The phenoxazine-embedded hexaphyrins showed similar NMR, absorption, and fluorescence patterns to the phenothiazine analogues but with noticeable shifts in peak positions. Electrochemical studies indicated that the phenoxazine-based systems are more electron-rich, which was further supported by DFT and TD-DFT calculations.

Palabras clave:

hexafirina fenoxazina fenotiazina macrocycles heterocyclic compounds organic chemistry supramolecular chemistry materials science

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