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Updated: Dec 21, 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

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从头到尾的包装,以促进 [2+2] 循环添加,以在特定配置中进行循环butan衍生物的绿色合成

Xiqiao Yang1, Liuyang Jin1, Jingbo Sun1

  • 1Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130021, P. R. China.

Chemistry (Weinheim an der Bergstrasse, Germany)
|March 17, 2025
PubMed
概括

分子包装显著影响拓 [2+2] 循环添加的结果. 从头到尾包装在二二烯增强反应性和选择性循环butan衍生物合成通过光二分化.

关键词:
化学选择性的化学选择性结合的二烯是联合的二烯.照相启动的 照相启动立体特异性 立体特异性在拓上 [2+2] 循环加法.

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相关概念视频

Cycloaddition Reactions: Overview01:16

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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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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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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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The chair conformation is the most stable form of cyclohexane due to the absence of angle and torsional strain. The absence of angle strain is a result of cyclohexane’s bond angle being very close to the ideal tetrahedral bond angle of 109.5° in its chair conformer. Similarly, the torsional strain is also absent owing to the perfectly staggered arrangement of bonds.
The hydrogen atoms linked to carbons are arranged in two different axial and equatorial orientations to achieve this...
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