在动力控制下催化区域选择性烯酸异构
Xufang Liu1, Wei Zhang1, Yujie Wang1
1Center of Basic Molecular Science (CBMS), Department of Chemistry , Tsinghua University , Beijing 100084 , China.
Journal of the American Chemical Society
|May 22, 2018
概括
这项研究引入了一种新的催化剂,用于区域选择性烯酸异构化,实现对具有挑战性的转换的动力控制. 该NNP-pincer连接体系统能够高选择性地有效的异构化功能化烯酸.
科学领域:
- 有机化学
- 催化剂
- 合成方法
背景情况:
- 氨酸异构对于合成内部氨酸和实现远程功能化至关重要.
- 在通常热力学控制的烯酸异构中实现动力控制仍然是一个重大挑战.
- 开发选择性催化系统对于促进有机合成至关重要.
研究的目的:
- 报告一种新的催化区域选择性烯酸异构反应.
- 使用可调节的NNP-pincer连接体来证明对区域选择性的动力控制.
- 建立一种温和而高效的功能化烯酸异构方法.
主要方法:
- 开发一种以为基础的催化系统,其中包括NNP-pincer连接物.
- 催化剂应用于各种1,1-非替代烯的异构.
- 研究一种选择性单异构化1-基到2-基的新策略.
- 涉及现场生成的Co-H物种的机制研究.
主要成果:
- 在olefin异构化中实现了高运动选择性控制.
- 对于一系列功能化烯来说,已证明出色的产量和区域选择性.
- 成功地应用了该方法来合成用于minfiensine总合成的关键中间体.
- 开发了一种选择性单异构化1-基到2-基的策略.
结论:
- 新型-NNP系统提供了一个强大的工具,用于在动力控制下区域选择性烯酸异构化.
- 催化系统温和,高效,多功能,适用于多种功能化的烯酸.
- 对β-H消除步骤的连接体控制要求选择性,有利于较少阻碍的产品.
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