Energy barriers to rotation in axially chiral quinazoline-4-ones

Hakgor A., Gunal Ş.

TETRAHEDRON, cilt.100, 2021 (SCI-Expanded, Scopus) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 100
  • Basım Tarihi: 2021
  • Doi Numarası: 10.1016/j.tet.2021.132506
  • Dergi Adı: TETRAHEDRON
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Chemical Abstracts Core, Chimica, EMBASE, Veterinary Science Database, Index Chemicus (IC)
  • Anahtar Kelimeler: Quinazolin-4-ones, Axial chirality, Energy barrier to rotation, Separation of enantiomers, Thermal racemization, ENANTIOSELECTIVE SYNTHESIS, ENANTIOMERIC SEPARATION, INTERNAL-ROTATION, DERIVATIVES, INHIBITORS, ACTIVATION, DISCOVERY
  • İstanbul Üniversitesi-Cerrahpaşa Adresli: Hayır

Özet

Axially chiral 2-thioxo-3-(o-aryl)-quinazolin-4-ones and 2-(benzylthio)-3-(o-aryl)-quinazolin-4-ones were synthesized and their energy barriers to rotation about the N-3-C-aryl bond were determined by thermal racemization of the separated enantiomers. The rotational barriers were found to range from 112.7 to 140.8 kJ/mol, depending on size of the ortho substituent and to increase linearly with the size of the van der Waals radii of the ortho-halogen substituents. Although the isolation of the enantiomers of the N-C axially chiral compounds bearing an ortho-fluoro substituent are rare because of small size of fluorine atom, we found that the rotational barriers of quinazolin-4-ones bearing an ortho-fluoro group are high enough allowing the isolation of enantiomers. (C) 2021 Elsevier Ltd. All rights reserved.