3,3'-Bis(trisarylsilyl) 替代的双甲酸稀土金属催化剂用于不对称的胺化
Denis V Gribkov1, Kai C Hultzsch, Frank Hampel
1Institut für Organische Chemie, Friedrich-Alexander Universität Erlangen-Nürnberg, Henkestrasse 42, D-91054 Erlangen, Germany.
新的奇拉稀土金属复合物有效催化氨基基的不对称胺化/循环化反应,实现高产率和高达95%的异能选择性. 这些催化剂还使性氨基的动态分辨率能够具有出色的二选择性.
科学领域:
- 有机金属化学 有机金属化学
- 不对称的催化剂.
- 稀土金属复合体 稀土金属复合体
背景情况:
- 在有机化学中,开发高效和选择性催化剂用于不对称合成至关重要.
- 化双甲酸是设计立体选择性催化剂的有价值的支架.
- 稀土金属为催化应用提供独特的易斯酸度和协调特性.
研究的目的:
- 为了合成新型的性3,3'-bis(trisarylsilyl) 替代的双甲酸稀土金属复合物.
- 评估这些复杂物在不对称的胺化/循环化反应中的催化活性.
- 研究这些催化剂在性氨基基的动态分辨率中的应用.
主要方法:
- 通过连接物交换反应合成奇拉稀土金属复合物.
- 使用合成的催化剂,对各种氨基的不对称胺化/循环化.
- 嵌合式α替代氨基基的动态分辨率.
- 确定反应动力学和激活参数.
- 结晶学分析用于绝对配置的确定.
主要成果:
- 成功合成了新型的奇拉双甲酸稀土金属复合物.
- 这些复合物在不对称的胺化/循环化中表现出高的催化活性,周转频率高达840小时-1和酶选择性高达95% ee.
- 在奇拉氨基烯的动态分辨率中,获得了优异的二元选择性 (7: 1 至 ≥50: 1).
- 激活参数表明,循环化反应具有高度组织的过渡状态.
- 催化剂 (R) -4a在抗马尔科夫尼科夫添加n-propylamine到styrene的过程中表现出活性.
结论:
- 基拉尔3,3'-bis(trisarylsilyl) 替代的双甲酸稀土金属复合物是不对称的胺化/循环化和动态分辨率的高效催化剂.
- 连接体和金属中心的固态和电子特性可以调整,以控制催化活性和选择性.
- 这些发现有助于开发用于酶选择性合成的先进催化系统.
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