Theoretical study of facial selectivity and regioselectivity in electrophilic addition reaction of chlorine to exo-tricyclo[4.2.1.0(2,5)]nona-3,7-diene


Abbasoglu R. , Yilmaz S.

INDIAN JOURNAL OF CHEMISTRY SECTION B-ORGANIC CHEMISTRY INCLUDING MEDICINAL CHEMISTRY, cilt.45, ss.1722-1728, 2006 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 45 Konu: 7
  • Basım Tarihi: 2006
  • Dergi Adı: INDIAN JOURNAL OF CHEMISTRY SECTION B-ORGANIC CHEMISTRY INCLUDING MEDICINAL CHEMISTRY
  • Sayfa Sayıları: ss.1722-1728

Özet

For prediction and interpretation of facial selectivity and regioselectivity of the electrophilic addition reaction to electricyclo[4.2.1.0(2,5)]nona-3,7-diene(exoTND) of chlorine, various models(geometric distortions, electron density, orbital effects, electrostatic effects and intermediates stabilities) have been used. Full geometric optimization of exoTND molecule has been done by ab initio and DFT methods and the structure of the molecule have also been investigated. Norbornene double bond(l) of molecule is endo pyramidalized and cyclobuten double bond(II) is also syn pyramidalized. The double bond(I) is more pyramidalized than the double bond(III) and it has higher reactivity. Exo face of the double bond(l) and anti face of the double bond(II) of the molecule are regions having much more electron density(q(i,HOMO)) and bigger negative potential. The exoTND-Cl-2 system has been investigated by B3LYP/6-31.1+G* method and their stable configurations have been determined. The exoTND...Cl-2(exo) and exoTND...Cl-2(anti) molecular complexes correspond to the most stable configurations of e.voTND-Cl-2 system. The most stable cation of bridged cationic intermediates is the exo-bridged chloronium cation. The results that are obtained by using the models for predicted and interpredicted facial selectivity and regioselectivity of the electrophilic addition reaction of chlorine to exoTND molecule agree with each other. Facial selectivity and regioselectivity of the addition reaction parallel the pyramidalization of the double bond.