1. Local Aromaticity in Naphtho-Annelated Fluoranthenes:Can the Five-Membered Rings Be More Aromatic Than the Six-MemberedRings?
- Author
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Radenković, Slavko, Tošović, Jelena, and Đurđević Nikolić, Jelena
- Subjects
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FLUORANTHENE , *AROMATIC compounds , *PREDICTION models , *CHEMICAL derivatives , *AROMATICITY - Abstract
All Kekulé-structure-basedtheories predict that the centralfive-membered ring in fluoranthene and naphtho-annelated fluoranthenesis nonaromatic. In the present work, a detailed study of the localaromaticity in a series of naphtho-annelated fluoranthene derivativeswas performed by means of the following aromaticity indices: the energyeffect (ef), bond resonance energy (BRE), multicenter delocalizationindices (MCI), harmonic oscillator model of aromaticity (HOMA) index,nucleus-independent chemical shifts (NICS), and ring current maps.It was found that, according to the ef, BRE, MCI, and HOMA values,the pentagonal rings in some naphtho-annelated fluoranthenes can beeven more aromatic than some hexagonal rings in the respective molecules.The magnetic indices do not support the results obtained by the energetic,electron delocalization, and geometrical aromaticity indices. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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