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Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions
Published on: July 28, 2022
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Reversible Ring Oxidation of 48π Planar Nonaphyrins to Open Shell 46π Dications
Tullimilli Y Gopalakrishna1,2, Ashokkumar Basavarajappa1, Hosahalli S Udaya1
1Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune, 411008, Maharashtra, India.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|March 5, 2025
Summary
Researchers synthesized novel 48π nonaphyrins, planar expanded porphyrinoids with unique electronic properties. These compounds undergo reversible oxidation, forming 46π dicationic diradicaloids confirmed by spectroscopy and calculations.
Area of Science:
- Organic Chemistry
- Supramolecular Chemistry
- Materials Science
Background:
- Expanded porphyrinoids are macrocyclic compounds with unique electronic and photophysical properties.
- Understanding structure-property relationships in these systems is crucial for developing new functional materials.
Purpose of the Study:
- To synthesize and characterize a novel class of 48π nonaphyrins.
- To investigate their electronic properties and structural topology.
- To explore their redox behavior and the nature of oxidized species.
Main Methods:
- Synthesis of 48π nonaphyrins.
- Single-crystal X-ray diffraction for structural analysis.
- Spectroscopic techniques (ESR, UV-Vis) and spectro-electrochemical measurements.
- Quantum chemical calculations.
Main Results:
- Successful synthesis and characterization of 48π nonaphyrins.
- Demonstration of planar structures with heterocycle-dependent topology.
- Observation of weak paratropic ring currents.
- Reversible two-electron oxidation to form 46π dicationic diradicaloid species.
- Confirmation of diradicaloid species via ESR, spectro-electrochemistry, and computational studies.
Conclusions:
- 48π nonaphyrins represent a novel class of expanded porphyrinoids with distinct electronic characteristics.
- Their planar structure and redox behavior open avenues for new electronic materials.
- The formation of diradicaloid species highlights unique electronic delocalization in these systems.
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