选择性C-H激活 haloalkanes 使用三pyrazolylborate复合物的使用
Andrew J Vetter1, Ryan D Rieth, William W Brennessel
1Department of Chemistry, University of Rochester, Rochester, New York 14627, USA.
这项研究探讨了基质如何与复合物反应,揭示了选择性的C-H键激活,并根据的位置影响反应途径. 这些发现影响有机金属化学和催化.
科学领域:
- 有机金属化学 有机金属化学
- 摄影化学的使用.
- 催化剂是一种催化剂.
背景情况:
- 光化学生成的复合物是反应性中间体.
- 化基具有C-H和C-Cl键激活的多种反应性.
研究的目的:
- 研究与[Tp'Rh(CNR) 的基质的C-H键裂解反应.
- 确定替代剂位置对激活通路和产品形成的影响.
- 分析甲激活产品的动力稳定性.
主要方法:
- [Tp'Rh(CNR) ]片段的光化学生成.
- 碎片与各种化 (1-,2-,甲,二甲,甲,甲,1-,1,1-二) 的反应.
- 对反应产物的分析,以确定C-H和C-Cl激活位点,并评估动力稳定性.
主要成果:
- 选择性终端C-H激活观察到与1-和3-烯.
- 2-烯产生了C-H激活和β-化物消除产品的混合物.
- 甲经历了C-H激活,而二甲显示了C-Cl裂变.
- 替代物的接近金属中心显著降低了减少性消除率.
- 有证据表明,用1-chloroalkanes和neopentyl chloride的α-chloro C-H激活产品.
- 循环基质产生的混合物是 diastereomeric 激活产品.
结论:
- [Tp'Rh(CNR) 片段与基质具有多种反应性,有利于C-H激活,但能够进行C-Cl裂变.
- 原子的位置决定了反应路径 (C-H与C-Cl激活,β消除).
- 替代剂影响有机金属中间体的动力稳定性,特别是影响减少性消除率.
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