Jove
Visualize
联系我们
JoVE
x logofacebook logolinkedin logoyoutube logo
关于 JoVE
概览领导团队博客JoVE 帮助中心
作者
出版流程编辑委员会范围与政策同行评审常见问题投稿
图书馆员
用户评价订阅访问资源图书馆顾问委员会常见问题
研究
JoVE JournalMethods CollectionsJoVE Encyclopedia of Experiments存档
教育
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab Manual教师资源中心教师网站
使用条款与条件
隐私政策
政策

相关概念视频

Aromatic Hydrocarbon Anions: Structural Overview01:18

Aromatic Hydrocarbon Anions: Structural Overview

2.8K
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...
2.8K
Aromatic Hydrocarbon Cations: Structural Overview01:18

Aromatic Hydrocarbon Cations: Structural Overview

2.9K
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group...
2.9K
Radicals: Electronic Structure and Geometry01:07

Radicals: Electronic Structure and Geometry

4.1K
This lesson delves into the geometry of a radical, which is influenced by the electronic structure of the molecule. The principle is similar to that of a lone pair, where the unpaired electron influences the geometry at the radical center.
Accordingly, the structure of a trivalent radical lies between the geometries of carbocations and carbanions. An sp2-hybridized carbocation is trigonal planar, while an sp3-hybridized carbanion is trigonal pyramidal. Here, the difference in geometry is...
4.1K
π Molecular Orbitals of 1,3-Butadiene01:24

π Molecular Orbitals of 1,3-Butadiene

9.3K
Conjugated dienes have lower heats of hydrogenation than cumulated and isolated dienes, making them more stable. The enhanced stabilization of conjugated systems can be understood from their π molecular orbitals.
The simplest conjugated diene is 1,3-butadiene: a four-carbon system where each carbon is sp2-hybridized and has an unhybridized p orbital that contains an unpaired electron. According to molecular orbital theory, atomic orbitals combine to form molecular orbitals such that the number...
9.3K
Photochemical Electrocyclic Reactions: Stereochemistry01:26

Photochemical Electrocyclic Reactions: Stereochemistry

1.9K
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
1.9K
π Molecular Orbitals of the Allyl Cation and Anion01:18

π Molecular Orbitals of the Allyl Cation and Anion

4.3K
An allyl group is a three-carbon conjugated system where the sp³-hybridized allylic carbon is bonded to a CH=CH2 group via a single bond. Allyl anions can be obtained by treating propene with a strong base that can deprotonate methyl groups. Allyl cations are formed as intermediates during substitution reactions involving allylic halides. In both cases, the hybridization of the allylic carbon changes from sp3 to sp2, giving rise to a carbon chain with three sp2-hybridized carbons, each with...
4.3K

您也可能阅读

相关文章

通过共同作者、期刊和引用图与本文相关的文章。

排序
Same author

n-Type Conjugated Polymer Based on a Carbonyl-Terminated Quinoidal Unit for Transparent Conductor.

Journal of the American Chemical Society·2026
Same author

Iridium-Catalyzed Regio- and Enantioselective Hydrogenation of 5‑Alkylidene Cyclopentenones.

Precision chemistry·2026
Same author

C-H Nucleophilic Substitution for the Diversity-Oriented Modification of Polycyclic Aromatic Hydrocarbons.

Journal of the American Chemical Society·2026
Same author

Pore Structure Variation of the Coalbed Methane Reservoir caused by Igneous Intrusion in the Zijinshan Block of the Eastern Ordos Basin, North China.

ACS omega·2025
Same author

Bis(azuleno)pentalenes with Six Consecutive Odd-Membered Rings.

Angewandte Chemie (International ed. in English)·2025
Same author

Lewis Acid-Catalyzed Condensation for Facile Synthesis of Quinoidal 2-(5-Methylenethiazol-2(5<i>H</i>)-ylidene)malononitrile End-Capped Shortwave Infrared Organic Semiconductors.

Journal of the American Chemical Society·2025
Same journal

Machine-Learning-Enabled Rapid Evolution of Photoenzymes for the Asymmetric Synthesis of gem-Difluorophosphonates.

Angewandte Chemie (International ed. in English)·2026
Same journal

Sequential H<sub>2</sub>S-Triggered Redox Relay Nanoprobes for Self-Sustained Chem-Illuminating Cascade Photodynamic Therapy.

Angewandte Chemie (International ed. in English)·2026
Same journal

Quantitative Active Hydrogen Modulation via Mastering Interfacial Water Over Single Rare Earth Atom on Copper for NO<sub>3</sub> <sup>-</sup>-to-NH<sub>3</sub> Electroreduction.

Angewandte Chemie (International ed. in English)·2026
Same journal

Unveiling the Role of Hydroxyls on Catalyst Surface in CO<sub>2</sub> Hydrogenation Reaction.

Angewandte Chemie (International ed. in English)·2026
Same journal

Strain-Release Pentafluorosulfanylation of Carbonyl-Containing Disubstituted Bicyclobutanes: A Fortuitous Path to SF<sub>5</sub>-Containing Oxa[2.1.1]bicyclohexanes.

Angewandte Chemie (International ed. in English)·2026
Same journal

Quantum Spin-1/2 Rings Built From [2]Triangulene Molecular Units.

Angewandte Chemie (International ed. in English)·2026
查看所有相关文章

相关实验视频

Updated: Jul 26, 2025

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
09:35

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units

Published on: September 18, 2016

11.6K

环代具有开放单片二极端特征的环代.

Qing Jiang1, Haipeng Wei1, Xudong Hou1

  • 1Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore.

Angewandte Chemie (International ed. in English)
|June 20, 2023
PubMed
概括
此摘要是机器生成的。

研究人员合成了迄今为止最大的环素 (CA) 分子,一种扩展的环素衍生物. 这种类似于石墨烯的分子表现出独特的开二基性质和两极性氧化还原行为,为新材料铺平了道路.

关键词:
芳香性是一种芳香性.环形黄 (Circumacenes) 是一种黄.具有激进的性格聚环芳香碳化合物 聚环芳香碳化合物齐格扎格的边缘

更多相关视频

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
10:44

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals

Published on: April 19, 2019

10.9K
Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
09:45

Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene

Published on: March 20, 2017

10.5K

相关实验视频

Last Updated: Jul 26, 2025

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
09:35

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units

Published on: September 18, 2016

11.6K
Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
10:44

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals

Published on: April 19, 2019

10.9K
Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
09:45

Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene

Published on: March 20, 2017

10.5K

科学领域:

  • 有机化学 有机化学
  • 材料科学 材料科学 材料科学
  • 超分子化学 超分子化学

背景情况:

  • 环 (Cas) 是具有独特结构的多环芳,具有由化环包围的核.
  • CAs的合成是复杂的,环甲是迄今为止最大的合成分子.
  • 稳定,大型,曲边缘的,具有激进特性的石墨烯样分子具有显著的兴趣.

研究的目的:

  • 为了合成和描述迄今为止最大的环烯分子.
  • 为了研究这种扩展的环烯衍生物的电子和结构性质.
  • 由于其独特的电子特性,探索材料科学中的潜在应用.

主要方法:

  • 合成一个扩展的环太生衍生物.
  • 进行X射线晶体分析以确认结构.
  • 实验和理论计算来研究电子属性.

主要成果:

  • 成功合成了迄今为止最大的环烯分子,一种扩展的环烯衍生物.
  • 证实了中度的开二基性质 (y0 = 39.7%) 和一个小的单元-三元能量差距 (ΔES-T = -4.47 kcal/mol).
  • 观察到主导的局部芳香性质,一个小的HOMO-LUMO间隙,和两氧化还氧化行为.

结论:

  • 这项研究提出了一种新型的大型环烯衍生物,扩大了合成的CA分子的范围.
  • 该分子表现出显著的二极根性质和独特的电子特性,使其成为先进材料的有希望的候选者.
  • 这项工作提供了一条新的合成途径,以实现稳定,多条状边缘的石墨烯样分子,具有开基因特性.