Paradigms and paradoxes: O- and N-protonated amides, stabilization energy, and resonance energy

被引：54

作者：

Morgan, Jessica ^{[2
]}

Greenberg, Arthur ^{[2
]}

Liebman, Joel F. ^{[1
]}

机构：

[1] Univ Maryland Baltimore Cty, Dept Chem & Biochem, Baltimore, MD 21250 USA

[2] Univ New Hampshire, Dept Chem, Durham, NH 03824 USA

来源：

STRUCTURAL CHEMISTRY | 2012年 / 23卷 / 01期

关键词：

Protonation of amides; Resonance stabilization in amides; Resonance energy; Acyl derivatives;

D O I：

10.1007/s11224-011-9851-7

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Protonation of amides most often occurs on oxygen, unless the amide bond is twisted out of planarity allowing the more favored nitrogen protonation to occur. Protonation of oxygen is believed to take place over that of nitrogen due to increased resonance stabilization of the O-protonated species. Resonance energies for O- and N-protonated dimethylacetamide are quantitated using quantum chemically calculated proton affinities for the two sites.

引用

页码：197 / 199

页数：3

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