双酸联体对以前无法获得的5个组成的N-异构体形成和功能化的影响
Erin E Plasek1, Roman G Belli1, Douglas M Kavaguti1
1University of Minnesota, Minneapolis, MN 55455 USA.
Organometallics
|September 8, 2025
概括
研究人员探索了稳定N-heteroarynes,发现与替代剂和短链接剂的特定素连接体使其形成并增强合反应中的反应性.
科学领域:
- 有机金属化学 有机金属化学
- 合成有机化学 合成有机化学
背景情况:
- 5个成员的N-heteroarynes以前被认为是合成难以获得的.
- 最近的进展利用双酸结合中心来稳定这些中间体.
研究的目的:
- 调查辅助素联体对5个成员N-heteroarynes的形成和反应性的影响.
- 为了确定成功的N-heteroaryne合成的最佳连接体结构特征.
主要方法:
- 合成和表征四个双酸联体,具有不同的替代剂和脊柱长度.
- 在催化N-heteroaryne形成中对这些配体的评估.
- 使用2-PyZnBr作为核友性合伙伴的反应性研究.
- 由此产生的-烯复合物的晶体分析.
主要成果:
- 使用基替代剂或连接器长度超过三个碳的配体是无效的.
- 具有一个,两个或三个碳链接物的基素替代剂促进了N-heteroaryne的形成.
- 改变的连接器长度显著提高了合反应中的区域选择性 (高达>20:1比率).
结论:
- 辅助氨酸配体的结构特征极大地控制了稳定5个成员N- heteroarynes的形成和反应性.
- 干骨干的长度在随后的合反应中实现高区域选择性中起着关键作用.
- 结晶学数据支持这样一个假设:Ni-aryne复合物的结构差异会影响区域选择性.
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