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Updated: Jul 23, 2025

Facile Preparation of 4-Substituted Quinazoline Derivatives
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Published on: February 15, 2016

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パラキノニメチドのダイラジカル性に関する計算と実験による確認

Zhipeng Pei1, Nicholas L Magann2, Madison J Sowden2

  • 1Institute for Nanoscale Science and Technology, Flinders University, Bedford Park 5042 South Australia, Australia.

Journal of the American Chemical Society
|July 18, 2023
PubMed
まとめ

パラキノネデメチド (p-QDM) は,TEMPOのようなラジカルトラップで容易な二分化と反応を可能にする,重要なオープンシェル型二基性特性を有する. この反応性により,関連する TCNQ 分子とは異なり,ポリメリゼーションが始まります.

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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...
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Radicals, the highly reactive species, gain stability by undergoing three different reactions. The first reaction involves a radical-radical coupling, in which a radical combines with another radical, forming a spin‐paired molecule. The second reaction is between a radical and a spin‐paired molecule, generating a new radical and a new spin‐paired molecule. The third reaction is radical decomposition in a unimolecular reaction, forming a new radical and a spin‐paired...
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The presence of electron-donating, electron-withdrawing, or conjugating groups adjacent to a radical center, imparts electronic stabilization to the radicals. Examples of such electronically-stabilized radicals are triphenylmethyl, tetramethylpiperidine‐N‐oxide, and 2,2‐diphenyl‐1‐picrylhydrazyl. These radicals are remarkably stable and are known as persistent radicals. Some of the persistent radicals can even be isolated and purified.
Along with electronic...
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Radicals can be formed by adding a radical to a spin-paired molecule. This is typically observed with unsaturated species, where the addition of a radical across the π bond leads to the production of a new radical by dissolving the π bond. For example, the addition of a Br radical to an alkene yields a carbon-centered radical.
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