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Updated: Aug 15, 2025

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
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Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones

Published on: February 7, 2019

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有机催化酶选择性热 [4 + 4] 循环添加剂

Vasco Corti1, Casper Larsen Barløse1, Niklas Lawaetz Østergaard1

  • 1Department of Chemistry, Aarhus University, Aarhus C DK-8000, Denmark.

Journal of the American Chemical Society
|January 5, 2023
PubMed
概括

这项研究引入了第一个有机催化不对称的 [4 + 4] 循环加法,用于构建奇拉八个成员的碳循环. 这种新方法可以有效地获得具有高立体控制的有价值的环氧八衍生物.

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Thermal cycloadditions are reactions where the source of activation energy needed to initiate the reaction is provided in the form of heat. A typical example of a thermally-allowed cycloaddition is the Diels–Alder reaction, which is a [4 + 2] cycloaddition. In contrast, a [2 + 2] cycloaddition is thermally forbidden.
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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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Some cycloaddition reactions are activated by heat, while others are initiated by light. For example, a [2 + 2] cycloaddition between two ethylene molecules occurs only in the presence of light. It is photochemically allowed but thermally forbidden.
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