Current time in Korea 04:04 Aug 20 (Tue) Year 2019 KCS KCS Publications
KCS Publications
My Journal Log In Register
HOME > Search > Browsing(BKCS) > Archives

Bulletin of the Korean Chemical Society (BKCS)

ISSN 0253-2964(Print)
ISSN 1229-5949(Online)
Volume 6, Number 5
May 20, 1985 

PMO Theory of Orbital Interactions (Part 7). σ-π Interactions
Byung Hoo Kong, Byung Choon Lee, Ikchoon Lee, Kiyull Yang
Orbital interactions of the types, σ-π, σ*-π, σ-π* and σ*-π* are investigated for the rotamers of α-X-acetones (X = F and Cl) using STO-3G method of calculation. It was found that the interactions are possible only in gauche forms, and the σ*-π* interactions are in general greater than the σ-π interactions due to the greater overlap, in spite of the greater energy gap involved; the greater σ*-π* interaction causes greater lowering of π* level relative to the lowering of σ in the σ-π interaction so that both σ-π* and n-π* interactions are enhanced in the gauche forms. The extra stability of the gauche form and the red shift in the n-π* transition are thus found to be natural corollaries of the greater σ*-π* interaction in the gauche forms.
277 - 279
Full Text