混合La-Li异金属复合物用于三级尼特罗阿尔多尔分辨率
Shin-ya Tosaki1, Keiichi Hara, Vijay Gnanadesikan
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
研究人员使用-异金属复合体开发了三级醇的动态分辨率. 这种方法有效地通过反-醇反应产生具有高反体过量的奇拉性醇.
科学领域:
- 有机化学 有机化学
- 不对称的合成方法
- 催化剂是一种催化剂.
背景情况:
- 三级醇是有价值的合成中间体.
- 它们的enantioselective合成的高效方法至关重要.
- 动力分辨率提供了一条途径,从racemic混合物中获得奇拉化合物.
研究的目的:
- 为了开发一个动态分辨率的racemic三级醇.
- 为了确定最佳的催化剂,以提高回复-尼特罗阿尔多尔反应的选择性.
- 为了实现高反体过剩 (ee) 和产品的回收产量.
主要方法:
- 使用混合的BINOL/双兰- (La-Li) 异金属复合物.
- 研究了种族三级酸的逆酸反应.
- 在2/1的比例中使用特定的La-Li3-(1a) 3 (LLB 2a) 和La-Li3-(1b) 3 (LLB* 2b) 复合体.
主要成果:
- 在动态分辨率中实现了高的enantioselectivity.
- 获得了具有80-97% ee. 的奇拉三级醇.
- 报告的回收率在30%-47%之间.
结论:
- 混合La-Li异金属复合物是三级醇的动力分解的有效催化剂.
- 描述的方法提供了一条可行的途径,以致于获得基丰富的基醇.
- 优化的催化剂混合物提高了反二醇反应的选择性和产量.
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