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站点选择性C-H和可切换的C-H/C-H 功能由缺电子Cp*CF3IrIII催化剂和光敏剂启用
Yuki Hirata1,2, Shunsuke Kimura2, Kosuke Higashida2
1Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo, Japan.
Angewandte Chemie (International ed. in English)
|December 16, 2024
概括
研究人员通过通过光诱导的E/Z异构化控制指导组定向,实现了选择性C(sp3) -H键功能化. 这扩大了C ((sp3) -H的功能范围,并使可切换的双C-H功能化策略成为可能.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 摄影化学的使用
背景情况:
- 选择性C-H键功能化在有机合成中至关重要.
- 引导群体辅助的CH激活通常面临着与竞争中的反应部位的挑战.
- 氧胺乙烯是多功能定向组,但它们在选择性C ((sp3) -H功能化中的应用需要精确的控制.
研究的目的:
- 制定一个战略,以选择性地址的C(sp3) -H债券功能化,而不是更具反应性的C(sp2) -H债券.
- 为了控制定向组的方向,利用氧化的光诱导E/Z异构化.
- 扩大氧化乙烯在 (((III) -催化C ((sp3) -H功能化的范围.
主要方法:
- 采用光诱导的E/Z同质化氧化以控制定向组的方向.
- 使用缺电子的Cp*CF3Ir(III) 催化剂进行C-H激活.
- 研究可切换的C-H激活序列,以实现连续的双重功能.
主要成果:
- 通过控制定向组几何学,在存在C-sp2-H键的情况下实现了选择性C-sp3-H功能化.
- 通过E/Z异构化和催化,扩大了C(sp3) -H功能化中氧化的基质范围.
- 演示可切换的C-H激活顺序,使相继的C-sp3) -H/C-sp2) -H和C-sp2) -H/C-sp3) -H双重功能成为可能.
结论:
- 氧化的光诱导E/Z异构化提供了一个强大的工具,用于控制C-H功能化的位点选择性.
- 开发的策略允许通过顺序和可切换的双C-H功能来构建复杂的分子.
- 这项工作为合成功能密集的有机结构提供了新的可能性.
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