易于在Pd.时形成Ar-CF3债券. 从[(Ph3P) 2Pd(CF3) Ph]和[(Xantphos) Pd(CF3) Ph]中减少性消除的结果显著不同
Vladimir V Grushin1, William J Marshall
1Central Research & Development, E. I. DuPont de Nemours and Co., Inc., Experimental Station, Wilmington, DE 19880-0328, USA. vlad.grushin-1@usa.dupont.com
Journal of the American Chemical Society
|September 28, 2006
概括
一种新的催化反应使得在低温下有效地三甲基化烯化合物. 这一突破促进了三甲基化的合成,这在制药和材料科学中至关重要.
科学领域:
- 有机金属化学 有机金属化学
- 化学 的化学
背景情况:
- perfluoroalkyl-aryl 的降解性消除是有机金属化学中的一个关键步骤.
- 开发高效的合成三甲基化的方法是很重要的,因为它们在制药,农业化学和材料科学中的应用.
研究的目的:
- 为了证明第一个易于和高度选择性的 perfluoroalkyl-aryl 从中心的减少性消除.
- 为了研究连接体结构对三甲基拉烯复合物的反应性的影响.
主要方法:
- 合成和表征[(Xantphos) Pd(Ph) CF3]复合物.
- 在不同温度下对[{Xantphos) Pd{Ph) CF3}的热分解的研究.
- 通过cis-chelating配体 (例如,dppe) 稳定类似复合物的比较研究.
- 使用分析技术分析分解产品的分析.
主要成果:
- [{Xantphos) Pd{Ph) CF3]在50-80°C时清洁地分解,产生具有高产率和选择性的三甲基 (CF3Ph).
- 具有刚性cis-chelating连接体 (dppe) 的类似复合体在130-140°C时是不反应的.
- 在酸 (PhI) 的存在下,[{Ph3P}2Pd{Ph}CF3]的分解产生了不同的产物,表明了不同的反应路径.
结论:
- 赞特斯配体促进了易于和选择性的甲基-基-基从拉的减少性消除.
- 连接物设计对于控制三甲基拉复合物的反应性至关重要.
- 这项研究为合成三甲基化烯提供了一个新的,高效的途径.
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