通过自组装的催化剂催化的芳香性化物添加高度反选择性
Xingshu Li1, Gui Lu, Wai Him Kwok
1Open Laboratory of Chirotechnology of the Institute of Molecular Technology for Drug Discovery and Synthesis and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong.
Journal of the American Chemical Society
|October 24, 2002
概括
一种新型的催化剂结合了BINOL和另一种连接物与异氧化物,有效地促进了对芳香性化物的对抗选择性基添加,达到99%以上的对抗选择性.
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:
- 对药品和精细化学品而言,酶选择性合成至关重要.
- 基试剂为碳-碳键形成提供了多功能构建块.
- 开发高效的催化剂用于不对称的化仍然是一个重大挑战.
研究的目的:
- 开发一种高度选择性催化剂,用于将基试剂添加到芳香性化物中.
- 在不对称的化中研究BINOL衍生系统的催化性能.
主要方法:
- 从BINOL (另一种配体) 和异氧化物 (Ti(OiPr) 4) 制备一种性催化剂.
- 在催化剂的存在下,芳香性化物与酸试剂的反应.
- 使用奇拉色谱学分析异构选择性.
主要成果:
- 开发的催化剂表现出异常高的反选择性,超过99% ee.
- 催化系统对基添加到一系列芳香性化物来说非常有效.
- 对于观察到的高反选择性来说,BINOL和二次配体与Ti ((OiPr) 4的组合是至关重要的.
结论:
- 一种用于不对称基化的一种新且高效的性催化剂已经成功开发出来.
- 这种催化系统代表了对抗选择性碳-碳键形成的重大进步.
- 该方法提供了一条实用的途径,可以从芳香性化物中提取出基醇.
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