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Disruption of Antiaromaticity in Structurally Related Expanded Porphyrin-like Macrocycles with Benzene Linkers

Thondikkal Sulfikarali1, Govind Behera1, Jayaprakash Ajay1

  • 1Indian Institute of Science Education and Research Thiruvananthapuram, Kerala 695 016, India.

Organic Letters
|December 20, 2021
PubMed

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Neutral hydrocarbons like cyclopentadiene with an odd number of carbon atoms and one intervening CH2 group in the ring are not aromatic. Cyclopentadiene with 4 π electrons does not satisfy the 4n + 2 π electron rule. Additionally, the intervening CH2 group is sp3 hybridized and lacks a vacant p orbital, thereby interrupting the overlap of p orbitals in a continuous manner and preventing the delocalization of π electrons throughout the ring.
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