迈克尔添加启动的Tandem Mannich循环中的立体选择性切换及其从胺扩展到乙烯基乙烯
Liu-Peng Zhao1, Sheng-Ye Zhang1, Hua-Kui Liu1
1The State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, CAS, University of Chinese Academy of Sciences, 345 Lingling Rd, Shanghai 200032, China.
Journal of the American Chemical Society
|July 4, 2023
概括
一个新的立体反转协议使得四环螺旋的选择性合成成为可能,这对生物活性类具有至关重要的意义. 这种方法促进了复杂分子合成的立体控制,包括.
科学领域:
- 有机化学
- 合成化学
- 医学化学
背景情况:
- 四环螺旋是许多生物活性醇中的核心结构.
- 由于有限的立体选择性控制,这些图案的不同合成具有挑战性.
研究的目的:
- 开发一个简单的立体反转协议来构建四环螺旋.
- 为了达到高立体选择性,进入单烯醇的二态同位素核.
主要方法:
- 迈克尔的加法启动了曼尼赫的双重循环.
- 机理研究包括现场核磁共振,对照实验和DFT计算.
- 对胺和乙烯基乙烯基基底物应用的立体选择性切换策略
主要成果:
- 为四环螺旋醇制造了一种新型的立体逆转方案.
- 反应通过罕见的C-C键裂变进行Mannich/re-Mannich重组.
- N-保护组和易斯酸催化剂的电子特性影响立体反转.
- 顺利的和甲基的总合成.
结论:
- 开发的协议可以轻松访问具有高选择性的二聚体螺旋核.
- 机理性见解使不同醇合成的立体选择性切换策略成为可能.
- 这种方法很实用,适用于复杂的天然产品的总合成.
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