Variable trends in R-X bond dissociation energies (R = Me, Et, i-Pr, t-Bu)

被引：72

作者：

Coote, ML ^{[1
]}

Pross, A

Radom, L

机构：

[1] Australian Natl Univ, Res Sch Chem, Canberra, ACT 0200, Australia

[2] Ben Gurion Univ Negev, Dept Chem, IL-84105 Beer Sheva, Israel

[3] Univ Sydney, Sch Chem, Sydney, NSW 2006, Australia

来源：

ORGANIC LETTERS | 2003年 / 5卷 / 24期

关键词：

D O I：

10.1021/ol035860+

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

High level ab initio molecular orbital calculations confirm experimental indications that the effect of alkyl substituents (R = Me, Et, j-Pr, t-Bu) on R-X bond dissociation energies varies considerably according to the nature of X. A simple qualitative explanation in terms of valence-bond theory is presented, highlighting the increasing importance of the stabilization of R-X by the ionic R+X- configuration for electronegative X substituents (such as F, OH, and OCH3).

引用

页码：4689 / 4692

页数：4

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