作为Pd催化氨基化反应的高度活性催化剂:使用基酸盐的交叉合反应和使用基化的初级氨基的高度选择性单化
Brett P Fors1, Donald A Watson, Mark R Biscoe
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|September 19, 2008
概括
一种新型的二甲基单胺联体BrettPhos能够使用甲基酸进行高效的C-N交叉合反应. 这种催化剂系统可以在低催化剂负载下实现氨酸和氨酸,甚至甲基胺的选择性单化.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 有机金属化学 有机金属化学
背景情况:
- 在有机合成中,C-N交叉合反应是基本的.
- 开发用于选择性氨基结的高效催化剂仍然是一个挑战.
- 与其他电友相比,基甲基酸是不那么有反应性的合伙伴.
研究的目的:
- 报告一种新的催化剂系统,该系统基于C-N交叉合的二甲基单胺联体 (BrettPhos).
- 为了证明化酸作为合伙伴在C-N键形成中的实用性.
- 为了实现初级阿利法胺和阿尼林的高度选择性单化.
主要方法:
- 布雷特斯配体的合成和表征.
- 使用布雷特的催化C-N交叉合反应.
- 对反应动力学和选择性的研究.
- 氧化添加复合物的结构分析.
主要成果:
- 基于BrettPhos的催化剂系统在C-N交叉合中表现出极好的反应性.
- 甲酸被成功地用作电友性合作伙伴.
- 实现了对原始阿利法胺和阿尼林单化的高选择性.
- 完成了第一个报告的甲基胺单化.
- 观察到低催化剂负载和快速反应时间.
结论:
- 布雷特是催化C-N交叉合反应的高效连接体.
- 催化剂系统扩大了C-N键形成反应的范围,包括基酸.
- 该联体使具有挑战性的氨基基底的选择性单化成为可能.
- 了解氧化添加复合体为催化剂的高反应性提供了机械的洞察力.
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