相关实验视频
Updated: Jul 8, 2026

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HKUST-1 as a Heterogeneous Catalyst for the Synthesis of Vanillin
Published on: July 23, 2016
富尔文斯,富尔文斯和阿布鲁文斯:它们是芳香的黑猩猩吗?
Helene Möllerstedt1, Mari Carmen Piqueras, Raül Crespo
1Department of Chemistry and Bioscience, Kemigården 3, Chalmers University of Technology, SE- 412 96 Göteborg, Sweden.
Journal of the American Chemical Society
|October 28, 2004
概括
,和青表现出"芳香色"的行为,适应它们的芳香度和电子状态之间的双极时刻. 这种适应性使它们能够在地面和兴奋状态下保持芳香性质.
科学领域:
- 理论化学 理论化学
- 有机化学 有机化学
- 量子化学 是一个量子化学.
背景情况:
- 赫克尔法则是基于pi电子数的阿努伦烯的芳香度.
- 贝尔德的理论预测了Hückel的规则在最低的三元状态 (T1) 中的反转.
研究的目的:
- 为了研究"芳香色"的概念在富尔文斯,富尔文斯和阿布鲁伦中.
- 探索如何芳香度和二极点在地面 (S0) 和兴奋电子状态 (T1,Q1) 之间发生变化.
主要方法:
- 应用贝尔德关于芳香度逆转的理论.
- 量子化学计算包括OLYP,CASSCF和CASPT2方法.
- 分析双极时刻,pi轨道群体和能量水平.
主要成果:
- 富尔维恩,富尔瓦伦和青都表现出"芳香色"的行为.
- 在T1 (对于富尔) 和Q1 (对于富尔和青) 中的双极时刻在大小上是可比的,但在方向上与S0状态相反.
- 这些分子可以通过调整共振结构,在S0和激发状态中实现芳香性.
结论:
- 研究的分子表现出适应性的芳香性,表现为"芳香色".
- 量子化学计算支持了黑在不同电子状态的行为假设.
相关概念视频
Olfaction
The sense of smell is achieved through the activities of the olfactory system. It starts when an airborne odorant enters the nasal cavity and reaches olfactory epithelium (OE). The OE is protected by a thin layer of mucus, which also serves the purpose of dissolving more complex compounds into simpler chemical odorants. The size of the OE and the density of sensory neurons varies among species; in humans, the OE is only about 9-10 cm2.
The olfactory receptors are embedded in the cilia of the...
The olfactory receptors are embedded in the cilia of the...
Aromatic Compounds: Overview
In general, the term ‘aromatic’ indicates a pleasant smell or fragrance from fresh flowers, freshly prepared coffee, etc. In the early history of organic chemistry, many benzene derivatives were isolated from the pleasant odor oils of the plants. For example, vanillin was isolated from the oil of vanilla, methyl salicylate from the oil of wintergreen, and cinnamaldehyde from the oil of cinnamon. They all had a pleasant odor; hence the name aromatic was given.
In 1825, Faraday isolated benzene...
In 1825, Faraday isolated benzene...
Criteria for Aromaticity and the Hückel 4n + 2 Rule
Like benzene, cyclobutadiene and cyclooctatetraene are cyclic compounds with alternate single and double bonds. However, their chemical behavior differs from benzene, as they are unstable and not aromatic. So, what are the structural characteristics of unsaturated compounds categorized as aromatic?
For the first time, Eric Hückel, a German chemical physicist, derived a set of structural features for a compound to be classified as aromatic. This is now known as Hückel’s rule or the 4n + 2 rule.
For the first time, Eric Hückel, a German chemical physicist, derived a set of structural features for a compound to be classified as aromatic. This is now known as Hückel’s rule or the 4n + 2 rule.
Aromatic Hydrocarbon Anions: Structural Overview
Neutral hydrocarbons like cyclopentadiene with an odd number of carbon atoms and one intervening CH2 group in the ring are not aromatic. Cyclopentadiene with 4 π electrons does not satisfy the 4n + 2 π electron rule. Additionally, the intervening CH2 group is sp3 hybridized and lacks a vacant p orbital, thereby interrupting the overlap of p orbitals in a continuous manner and preventing the delocalization of π electrons throughout the ring.
Due to the absence of continuous overlap of p...
Due to the absence of continuous overlap of p...
Structures of Aldehydes and Ketones
Vanillin—a flavoring agent in vanilla, cinnamaldehyde—a molecule responsible for the distinct smell of cinnamon, and acetone—a strong-smelling ingredient in nail polish removers, all belong to a class of carbonyl compounds called aldehydes and ketones (Figure 1). Although both aldehydes and ketones contain the characteristic carbonyl (C=O) bond, their chemical structures vary with respect to the groups directly attached to the carbonyl carbon.
In aldehydes (Figures 1a and 1b), the carbonyl...
In aldehydes (Figures 1a and 1b), the carbonyl...
UV–Vis Spectroscopy: Woodward–Fieser Rules
UV–Visible absorption spectra of conjugated dienes arise from the lowest energy π → π* transitions. The light-absorbing part of the molecule is called the chromophore, and the substituents directly attached to the chromophore are called auxochromes. A strong correlation exists between the absorption maxima, λmax, and the structure of a conjugated π system. The Woodward–Fieser rules predict the value of λmax for a given structure by adding the contributions...

