稳定的亚氧化物和乙基衍生物之间的循环添加反应中的区域选择性逆转
Yuki Maeda1, Yoshimitsu Hashimoto1, Ryo Aoki1
1Showa Pharmaceutical University, 3-2-1 Higashi-Tamagawagakuen, Machida, Tokyo 194-8543, Japan.
Chemical & pharmaceutical bulletin
|November 26, 2025
概括
稳定的氧化物经历1,3-双极循环添加与基和碳化合物. 素组逆转了区域选择性,产生了可转化为4-基素的5-iminoisoxazoles.
科学领域:
- 有机化学 有机化学
- 异环化学 异环化学
背景情况:
- 1,3-双极循环添加是有机合成中的一个关键反应.
- 氧化物是用于循环添加反应的多功能1,3-二极体.
- 循环添加的区域选择性可以受到替代电子效应的影响.
研究的目的:
- 为了研究稳定的亚氧化物与α,β-基化和碳化合物的1,3-双极循环添加反应.
- 探索水组对循环添加的区域选择性的影响.
- 为了证明由此产生的5-iminoisoxazoles的转化为4-acylisoxazoles.
主要方法:
- 稳定的亚氧化物与α,β-基化的反应.
- 稳定的氧化物与α,β-基碳化合物的反应.
- 在5-iminoisoxazoles的脱水区.
主要成果:
- 氧化与α,β-基尼尔化的循环添加产生了5-iminoisoxazoles.
- 氧化与α,β-基尼尔碳基化合物的循环添加产生了4-基.
- 在与基尼尔化的反应中,由于电子捐赠化组,区域选择性被逆转.
- 5-iminoisoxazoles通过脱水区成功地转化为4-acylisoxazoles.
结论:
- 1,3-双极循环添加反应提供了一个容易通往5-iminoisoxazoles和4-acylisoxazoles的途径.
- 电子捐赠的素组在指导循环添加的区域选择性方面发挥着至关重要的作用.
- 合成的5-iminoisoxazoles可以作为制备4-acylisoxazoles的有价值的中间体.
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