非活性基的分子内氧基化
Zhi Xu1, Yougant Airan1, Martin Tomanik1
1Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States.
Tetrahedron
|June 24, 2024
概括
基二氧化的分子内循环化通常会产生循环. 然而,这项研究表明,双循环系统中的电子无偏主要经历氧基化,这是一个罕见的反应途径.
科学领域:
- 有机化学 有机化学
- 合成化学 合成化学
- 反应机制 反应机制
背景情况:
- 在有机合成中,通过基二乙循环合成的环胺合成是一种成熟的方法.
- 之前试图合成塞斯基特类欧欧尼米诺的尝试涉及在6-oxa-bicyclo[3.2.1]-oct-3-ene框架内对合基二的分子内循环化.
研究的目的:
- 在一个双循环系统中,研究一个基二聚与一个电子无偏向基的分子内循环化.
- 为了探索相关基质观察到的氧基化途径的普遍性.
主要方法:
- 合基二氧化的分子内循环.
- 6-oxa-bicyclo[3.2.1]-oct-3-ene衍生物的合成.
- 使用光谱方法分析反应产品.
- 与更简单的α-diazo β-ketoesters进行竞争实验.
主要成果:
- 内分子循环化只能产生一个氧基化产物,涉及1,2-添加氧和碳到基.
- 氧基化被发现是各种6-oxa-bicyclo[3.2.1]-oct-3-ene基质的一般反应.
- 还观察到,这些氧基化产物在更简单的α-diazo β-ketoesters的循环形成中具有竞争力.
结论:
- 在6-oxa-bicyclo[3.2.1]-oct-3-ene系统内,对于电子无偏的基,氧化化途径比循环化更受青.
- 过渡状态中电荷分离的增加似乎促进了氧基化反应.
- 这一发现扩大了已知的基二氧化的活性,并提供了对反应机制控制的见解.
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