A DFT Study on Push-Pull (Amino-Nitro) Fulminenes and Hexahelicenes

TÜRKER B. L., Bayar C. C., Balaban A. T.

POLYCYCLIC AROMATIC COMPOUNDS, cilt.30, sa.2, ss.91-111, 2010 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 30 Sayı: 2
  • Basım Tarihi: 2010
  • Doi Numarası: 10.1080/10406631003756005
  • Dergi Adı: POLYCYCLIC AROMATIC COMPOUNDS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.91-111
  • Anahtar Kelimeler: hexahelicenes, fulminenes, push-pull (donor-acceptor) groups, DFT, NICS(0), SEMIEMPIRICAL METHODS, ABSOLUTE HARDNESS, FREE-RADICALS, PI-ELECTRONS, CIRCULAR-DICHROISM, CHEMICAL-SHIFTS, AROMATICITY, RINGS, OPTIMIZATION, PARAMETERS
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

In order to investigate the steric and electronic effects of electron-donor (amino) and -acceptor (nitro) substituents on hexahelicene and fulminene (isomeric and isoarithmic compounds), sixteen different types of terminal-amino-nitro hexahelicenes (H1-H16) and fulminenes (F1-F16) have been designed and investigated theoretically by the DFT method at B3LYP/6-31G(d) level. Besides electronic and thermodynamic properties, aromaticities (via NICS(0) calculations) have also been discussed for the above sets of terminal-rings-substituted hexahelicenes and fulminenes having 16 isomers each. Steric hindrance, seen enhanced in Hn structures, affects the total energies and heat of formations. The quinonoid conjugation is a minor factor in determining the trends in ring aromaticity of the above structures.