在不对称催化中管理高度协调的基质:用基于的三元催化剂进行催化不对称氨化
Tomoyuki Mashiko1, Naoya Kumagai, Masakatsu Shibasaki
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
Journal of the American Chemical Society
|September 30, 2009
概括
一种新型的/胺基催化剂使得具有高产量和酶选择性,具有高产量和酶选择性的胺基和α-基胺基等具有挑战性的基质的不对称氨基化成为可能. 这一突破为不对称催化剂提供了新的可能性.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 不对称的合成方法
背景情况:
- 催化不对称氨化对于合成性分子至关重要.
- 为具有挑战性的基质开发高效的催化剂仍然是有机合成的关键目标.
研究的目的:
- 开发一种基于/胺的新型催化剂系统,用于不对称的氨基化.
- 为了研究触媒性能和挑战基板的机制.
主要方法:
- 作为催化剂系统使用了酸六酸, (R) - 3a和H-d-Val-O(t) Bu.
- 采用光谱分析,控制实验和机械研究的动力学研究.
- 应用催化剂对顺胺衍生物和N-非替代的α-alkoxycarbonyl amides的不对称氨基化.
主要成果:
- 在1mol%的催化剂负载下,实现了未受保护的苏胺衍生物1的催化不对称氨基化.
- 对于前所未有的N-非替代的α-alkoxycarbonyl amides,证明了有效性,产生高达99%的产量和99%的反体过剩 (ee) 的产品.
- 确定了一个三元复合体,涉及La(NO(3))(3)*6H(2)O/(R)-3a/H-d-Val-O(t) Bu作为可能的活性物种.
结论:
- /胺催化剂系统表现出高的催化性能和反催化控制.
- 在过渡状态下,通过 lanthanum 协调和合作性结合激活基质是反应成功的关键.
- 这种方法扩大了不对称氨基化的范围,以以前无法进入的基质.
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