区域选择性C(sp3) -H玻利化通过sp2-sp3 diboranes中的一个diarylboryl离子替代物(5)
Xiaofeng Mao1, Jie Zhang1, Zuowei Xie2
1Department of Chemistry, The Chinese University of Hong Kong Shatin, N. T. Hong Kong China jiezhang@cuhk.edu.hk.
Chemical science
|November 14, 2025
概括
无过渡金属的C-H功能化是一个关键目标. 这项研究引入了一种新的方法,用于区域选择性C(sp3) -H玻利化,使用diarylboryl离子替代物,使新的合成途径成为可能.
科学领域:
- 合成化学 合成化学
- 有机金属化学 有机金属化学
- 主组化学 主组化学
背景情况:
- 没有过渡金属的C-H功能化是一个重大挑战.
- 由于反应性较低,现有的主要组方法在C ((sp3) -H功能化方面遇到了困难.
- sp2) -H激活比 sp3) -H激活更发达.
研究的目的:
- 开发一种新的没有过渡金属的方法,用于区域选择性C ((sp3) -H玻利化.
- 探索反应性二甲基阳离子替代物在C-H激活中的实用性.
- 扩大主组元素介导的C-H功能化的范围.
主要方法:
- 使用的sp2-sp3 diboranes ((5) 由一个B ((o-tolyl) 2−替代物介导.
- 在基组的α-C(sp3) -H键中实现了选择性插入.
- 使用TMSOTf用于将阳离子中间体转化为中性gem-diborylalkanes.
- 在缺乏α-C(sp3) -H键的基质中研究了β-C(sp3) -H激活.
- 进行竞争实验和DFT计算以确定选择性.
主要成果:
- 在基组的α位置上报告了区域选择性C ((sp3) -H玻利化.
- 产生了一系列的阳离子1,1-二玻里基基物种.
- 已证明成功转化为中性宝石-二甲基.
- 观察到β-C(sp3)-H激活,在特定基质中产生有机盐和烯酸.
- 确立了对α-而不是β-C(sp3)-H激活的明确偏好.
结论:
- 反应性二甲基阳离子替代物是区域选择性C(sp3) -H玻利化的有效试剂.
- 开发的方法扩大了主组元素介导的C-H激活的合成效用.
- DFT计算为观察到的C-H激活选择性提供了机械洞察力.
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