挫败的β-化物消除. 由电友金属离子对催化的alpha-chloronorbornene选择性烯化
Aswini K Dash1, Tryg R Jensen, Charlotte L Stern
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, USA.
Journal of the American Chemical Society
|September 30, 2004
概括
新的单位聚合催化剂有效地用α-chloro-norbornene对芳香分子进行基化. 这些催化剂区域选择性地产生具有高周转频率的外-1-chloro-2-arylnorbornane产品.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 有机合成 有机合成
背景情况:
- 单位聚合催化剂可以精确控制聚合物结构.
- 金属和相关复合物是有机转化中的多功能催化剂.
- 金属基复合物的激活与非协调的 counterions 产生高度电友的物种.
研究的目的:
- 为了研究新型单位聚合催化剂的催化活性,用于芳香化.
- 探索化反应的区域选择性和立体选择性.
- 阐明反应机制并确定关键中间体.
主要方法:
- 在Cp*MMe(3), (CGC) MMe(2) 和Cp(2) ZrMe(2) 前体 (M = Ti, Zr) 的催化剂在现场生成.
- 使用Ph(3)C(+)B(C(6)F(5))(4)(-) 或孤立的离子对复合物的激活.
- 芳香分子 (,) 与α-chloronorbornene的反应.
- 使用NMR,GC-MS和元素分析对产品的表征.
- 通过二维NMR和X射线晶体学进行立体化学分析.
主要成果:
- 催化剂区域选择性地提供高产量的exo-1-chloro-2-arylnorbornane产品.
- 用标记的产品是使用化芳溶剂合成的.
- 观察到高周转频率超过120小时 (-1).
- 亚里尔组的立体化学证实为异物.
- 机制可能涉及金属电友的参与.
结论:
- 新型单位催化剂对芳香化合物的区域选择性化有效.
- 反应过程具有很高的外立体选择性.
- 催化系统显示出高效率和有机合成进一步发展的潜力.
相关概念视频
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