催化不对称的α-Iminol重排:新的合平台
Xin Zhang1, Richard J Staples, Arnold L Rheingold
1Department of Chemistry, Michigan State University , East Lansing, Michigan 48824, United States.
Journal of the American Chemical Society
|September 24, 2014
概括
研究人员发现了一种新的基于的性催化剂,用于将α-基胺转化为α-氨基基. 这种高度选性催化剂在各种基质上实现了优异的产量和余 (ee).
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:
- 将α-基因胺重新排列为α-氨基基是有机合成中至关重要的转化.
- 为这种反应开发高效的性催化剂,特别是那些涉及1,2-碳转移的催化剂,仍然是一个重大挑战.
研究的目的:
- 确定第一个能够通过1,2碳转移调解α-基因胺到α-氨基基子的不对称重新排列的性催化剂.
- 选多样化的非对称催化剂库,以找到最有效的这种转换.
主要方法:
- 对19种不同的不对称催化剂进行选,包括VAPOL,VANOL及其衍生物.
- 使用X射线衍射的最有效催化剂的详细描述.
主要成果:
- 瓦波尔 (VAPOL),瓦诺尔 (VANOL) 和7,7'~t) Bu2VANOL的酸盐复合物表现出显著的催化活性,达到高达88%的反体过量 (ee).
- 作为最佳催化剂,VANOL的复合物出现了,在大多数基质中产生了97~99%的EE.
- X射线衍射分析显示,催化剂是一种同质复合体,含有三个VANOL配体和两个质子化N-甲基伊米达.
结论:
- 一种基于的新且高效的性催化剂已经开发出来,用于对α-hydroxy imines进行非对称的重新排列.
- 这种催化剂显著促进了具有高反选择性的α-氨基的合成,为有机化学家提供了宝贵的工具.
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