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Updated: May 10, 2026

Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
07:12

Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions

Published on: July 17, 2020

通过光化学 [2 + 2] 循环添加进行二碳衍生金属循环的合成后修饰

Ying-Feng Han1, Guo-Xin Jin, F Ekkehardt Hahn

  • 1Institut für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 30, D-48149 Münster, Germany.

Journal of the American Chemical Society
|June 5, 2013
PubMed
概括

从金属离子和新型连接体中形成的新分子正方形可以在合成后使用紫外线进行修改. 这一过程产生了循环butan结构,具有从银复合体中恢复带的潜力.

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Cycloaddition Reactions: Overview

Cycloadditions are one of the most valuable and effective synthesis routes to form cyclic compounds. These are concerted pericyclic reactions between two unsaturated compounds resulting in a cyclic product with two new σ bonds formed at the expense of π bonds. The [4 + 2] cycloaddition, known as the Diels–Alder reaction, is the most common. The other example is a [2 + 2] cycloaddition.
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Cycloaddition Reactions: MO Requirements for Photochemical Activation

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[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction

The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.
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