不同质地催化C=C键的不对称化,由表面绑定的性修饰剂指导
David J Watson1, R J Bennie Ram John Jesudason, Simon K Beaumont
1Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom.
Journal of the American Chemical Society
|September 17, 2009
概括
这项研究引入了奇拉硫化物连接物用于异质的enantioselective催化化异相,达到多达100周转. 配体设计,特别是替代剂散量,显著影响了对纳米颗粒的不对称诱导.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
背景情况:
- 在有机合成中,C=C键的不对称化是至关重要的,通常使用的是均的有机金属催化剂.
- 开发异构的催化剂来进行化,是一个巨大的挑战,需要对表面反应进行控制.
研究的目的:
- 为了实现异质的enantioselective催化化,使用在拉纳米颗粒上固定的奇拉连接物.
- 为了研究联结体结构对异对称诱导在异的化作用的影响.
主要方法:
- 合成六种具有 pyrrolidine 和硫化物功能的奇拉硫化物联体.
- 在异质催化过程中将连接器连接到纳米颗粒.
- 使用高分辨率X射线光电谱学 (XPS) 进行表征.
- 在异子化中对催化性能的评估.
主要成果:
- 首次成功地实现了异质的enantioselective催化化异.
- 配体吸附仅在纳米颗粒上得到证实,而不是在碳支上.
- 对抗选择性营业额的数字达到大约100个.
- 不对称的诱导与连接体结构有显著的变化;较大的基团导致较高的反体过量.
结论:
- 化硫化联体可以有效地调解化在纳米颗粒上的异质选择性化.
- 在被替代体体积影响的表面上的联体分散对于不对称的诱导至关重要.
- 连接体刚性和抗自我组装单层形成的阻力是改进的性修饰剂的关键设计原则.
相关概念视频
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