相关实验视频
Updated: Jul 14, 2026

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Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
在α,β不和基,基,基,基和基中的酸度趋势
J F Gal1, M Decouzon, P C Maria
1Chimie des Matériaux Organiques et Métalliques, Université de Nice-Sophia Antipolis, Parc Valrose, 06108 Nice Cedex 2, France.
Journal of the American Chemical Society
|June 28, 2001
概括
气相酸度测量显示,碳,,和锡的不和化合物比和化合物更强的酸. 酸性向下14组增加,不和碳化合物显示最显著的酸化效应.
科学领域:
- 有机金属化学 有机金属化学
- 物理化学 物理化学
- 计算化学的计算化学
背景情况:
- 了解有机金属化合物的内在酸度对于预测它们的反应性至关重要.
- 14组元素 (C,Si,Ge,Sn) 呈现出不同的化学性质,受它们在周期表中的位置的影响.
- 不和对酸度的影响以前已经在有机和无机化合物中进行了研究.
研究的目的:
- 测量和比较乙烯基,乙烯基,乙烯基和基替代的西兰,基尔曼和斯坦南的气相酸度.
- 用计算方法分析不和对14组化合物的酸度的影响.
- 阐明14组内的酸度趋势,并将其与相应的碳化合物进行比较.
主要方法:
- 气相酸度测量使用里埃转换离子旋回子共振 (FT-ICR) 技术.
- 使用G2 ab initio和密度函数理论 (DFT) 计算的计算分析.
- 实验和理论酸度数据的比较分析.
主要成果:
- 酸度通常在第14组下升,和锡衍生物之间的差异较小.
- C,Si,Ge和Sn的α,β不和化合物是比它们的和类似物更强的酸.
- 不和的酸化效应在碳化合物中明显明显于含有Si,Ge和Sn的化合物中,这是由于基离子的优异共振稳定.
结论:
- 不和会增加14组化合物的酸度,主要是通过增加离子稳定.
- 不和碳团的电子负性随着不和而增加,从而增加了酸度.
- 乙烯基衍生物是系统地比衍生物更强的酸,实验数据与这些发现一致.
相关概念视频
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In the absence of any leveling effect, the acid strength of binary compounds of hydrogen with nonmetals (A) increases as the H-A bond strength decreases down a group in the periodic table. For group 17, the order of increasing acidity is HF < HCl < HBr < HI. Likewise, for group 16, the order of increasing acid strength is H2O < H2S < H2Se < H2Te. Across a row in the periodic table, the acid strength of binary hydrogen compounds increases with increasing...
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This lesson delves into a critical aspect of the relative strengths of acids and bases. The strength of an acid is evaluated by the acid dissociation into its conjugate base and a hydronium ion in water. The complete dissociation of a strong acid is confirmed with a very high concentration of hydronium ions. As a result, an incomplete dissociation process affirms a weak acid. Therefore, the equilibrium is in the forward direction for strong acids and backward for weak acids in these reactions.
Molecular Structure and Acidity
An acid can be deprotonated to form a conjugate base or an anion. If the produced anion is more stable, then the acid is stronger. On the contrary, if the anion is unstable, then the acid is weaker. Hence, to determine the acidity of the compound, the stability of its conjugate base is studied using various factors.
The size effect explains the change in atomic size on acidity. When comparing the acids formed from elements that belong to the same column in the periodic table, their atomic sizes...
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The Leveling Effect of a Solvent
A generic acid (HA) reacts with the generic base (B-) to yield the corresponding conjugate base (A-) and conjugate acid (HB):
The Leveling Effect of a Solvent
A generic acid (HA) reacts with the generic base (B-) to yield the corresponding conjugate base (A-) and conjugate acid (HB):

