酸促进基基烯的形成:与烯酸三元化催化相关的循环外中间体
Aaron Sattler1, David G VanderVelde, Jay A Labinger
1Arnold and Mabel Beckman Laboratories of Chemical Synthesis, California Institute of Technology , Pasadena, California 91125, United States.
Journal of the American Chemical Society
|July 10, 2014
概括
为乙烯和α-olefin三元化合成了两种新型的氧胺前催化剂. 一种预催化剂有效地产生1-hexene和C15烯酸,而另一种则表现出复杂的反应性,但仍然可以实现烯酸三元化.
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.
- 聚合物科学 聚合物科学
背景情况:
- 乙烯和α-olefin的三元化是生产有价值化学品的关键反应.
- 开发高效和选择性的前催化剂是推动烯酸转化技术发展的关键.
- 基于的复合物为催化烯寡合化提供了有前途的途径.
研究的目的:
- 为了合成和表征新的氧胺预催化剂.
- 研究这些前催化剂在乙烯和α-olefin三元化中的催化活性.
- 阐明激活机制和反应途径,包括循环外反应.
主要方法:
- 使用X射线衍射的前催化剂的合成和结构特征.
- 用三五甲 (BC6F5) 3) 激活预催化剂.
- 光谱分析 (NMR) 用于在低温下监测反应中间体和机制.
- 在乙烯和1-三元化中的催化性能评估.
主要成果:
- 两种新的氧胺预催化剂 (FI) Ti (CH2SiMe3) 2Me和 (FI) Ti (CH2CMe3) 2Me已成功合成和表征.
- (FI) Ti ((CH2SiMe3) 2Me与B ((C6F5) 3) 激活,有效地将乙烯三聚化为1-hexene和1-pentene,成为C15的olefins.
- 烯类型 (FI) Ti ((CH2CMe3) 2Me 具有复杂的低温反应性,包括α-消除和分子内转化,但仍然是烯三聚化有效的前催化剂.
结论:
- 合成的氧胺复合物代表了乙烯和α-olefin三元化有效的前催化剂.
- 该研究揭示了不同的激活途径和中间物种,取决于连接体替代剂.
- 尽管循环之外的途径,neopentyl预催化剂表现出强大的催化活性,突出显示了这些系统的多功能性.
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