在Curtin-Hammett控制下运行的立体分离/立体融合路径的催化,非对称迈克尔-阿尔多尔取消
Mitchell T Giordano1, Katelyn M Kitzinger1, Pedro de Jesús Cruz1
1Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States.
Journal of the American Chemical Society
|May 22, 2023
概括
一种新的双功能伊米诺 (BIMP) 催化方法有效合成功能化环醇. 这种多米诺反应产生了五个具有高选择性的立体中心,为复杂分子提供了实用途径.
科学领域:
- 有机化学
- 催化剂
- 立体选择合成
背景情况:
- 在有机合成中,开发有效的催化方法来构建复杂的循环分子至关重要.
- 在单个反应级联中控制多个立体中心仍然是一个重大挑战.
- 以前的立体融合合成通常依赖于结晶驱动的机制.
研究的目的:
- 开发一种用于密集功能化环醇的立体选择性合成的新型催化系统.
- 调查迈克尔/阿尔多尔多米诺反应中立体控制的机制.
- 建立一种具有多个连续立体中心的分子生成的实用和有效方法.
主要方法:
- 使用双功能伊米诺 (BIMP) 催化剂.
- 使用迈克尔/阿尔多尔多米诺反应序列.
- 通过动力学研究和计算分析研究反应机制.
主要成果:
- 实现了多达五个连续立体中心的密集功能化环醇的合成.
- 已证明具有较高的二元选择性 (高达> 20: 1) 和反选择性 (高达> 99: 1).
- 阐明了由柯廷-哈梅特动力学驱动的立体融合循环机制,与由结晶驱动的过程不同.
结论:
- BIMP催化多米诺反应为构建高度功能化的环醇提供了强大而高效的策略.
- 反应通过动态控制的循环,为立体融合提供了一个新的范式.
- 该方法产生分析纯的晶体产品,简化了分离和净化.
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