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Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
Macrocyclic aromaticity in Hückel and Möbius conformers of porphyrinoids
Jun-ichi Aihara1, Hideki Horibe
1Department of Chemistry, Faculty of Science, Shizuoka University, Oya, Shizuoka, 422-8529, Japan.
Abstract:
Macrocyclic aromaticity is one of the key concepts in porphyrin chemistry. The degree of macrocyclic aromaticity and the associated main macrocyclic conjugation pathway in Hückel- and Möbius-type porphyrinoids were determined using our recently proposed procedure based on bond resonance energy (BRE). All porphyrinoids with diatropic and paratropic macrocycles were found to have positive and negative superaromatic stabilization energies (SSEs), respectively. Main macrocyclic conjugation pathways predicted for various porphyrinoids were exactly the same as those predicted from the annulene model for porphyrinoids. Thus, macrocyclic aromaticity of Hückel and Möbius porphyrinoids has been rationalized successfully using an energetic criterion of aromaticity.
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