区域选择性非对称的C(60) 通过催化剂进行四环聚合
Masakazu Nambo1, Atsushi Wakamiya, Shigehiro Yamaguchi
1Department of Chemistry, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan.
Journal of the American Chemical Society
|November 19, 2009
概括
一个新的催化反应使得C(60) 富勒烯的选择性四聚合,产生具有高区域选择性的四聚合富勒烯. 这种方法可以精确地控制完整的功能.
科学领域:
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
背景情况:
- 富勒,如C 60),是具有独特电子和结构性质的碳基.
- 富勒的功能化对于为各种应用量身定制它们的特性至关重要.
- 催化反应是有机合成中的多功能工具,可以构建复杂的分子.
研究的目的:
- 建立一个催化四聚化方法,用于C(60) 富勒伦.
- 为了实现富勒烯的选择性和区域选择性功能化.
- 调查观察到的选择性背后的机制.
主要方法:
- 在有催化剂 (PdCl2[P(OPh) 3) 2) 的情况下,用化和属处理C(60).
- 在50°C的1,2-二二中进行反应.
- 涉及反应中间体和区域选择性分析的机制研究.
主要成果:
- 这种反应成功地产生了四聚合富勒,产量高达74%.
- 对应显示出几乎完全的区域选择性,表明对加法模式的精确控制.
- 机理学研究表明,一种途径涉及通过 bis ((pi-allyl) palladium中间体连续的核性/电性化.
结论:
- 已经开发出一种新的Pd催化C(60) 的四聚化,为功能化的富勒伦提供了选择性途径.
- 高的区域选择性归因于固体和电子因素的组合,这些因素影响了结合的步骤.
- 这种方法为复杂烯衍生物的受控合成提供了一种有价值的方法.
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