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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
通过催化剂控制的立体选择性环闭转化合成宏环自然产品
Miao Yu1, Chenbo Wang, Andrew F Kyle
1Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, USA.
Nature
|November 5, 2011
概括
这项研究引入了一种新的基于的环闭转化酶 (RCM) 催化剂,该催化剂精确控制类立体化学. 这一突破使复杂的宏环分子的高度立体选择性合成成为可能,改善了天然产品的合成.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 自然产品的合成自然产品的合成
背景情况:
- 二键的立体化学特征对于许多自然产品的生物活性至关重要.
- 催化环闭转解 (RCM) 是合成大型不和环的关键方法,但往往缺乏立体化学控制.
- 这种缺乏控制在复杂合成中是有问题的,特别是当RCM是后期转换时.
研究的目的:
- 通过催化RCM开发一种实用和通用的方法,用于通过催化RCM对宏环基的高度立体选择性合成.
- 为了应对在RCM反应中控制烯立体化学的挑战.
- 为了证明新方法在合成复杂的自然产品中的实用性.
主要方法:
- 开发和应用一种新的基于的基基催化剂,用于RCM.
- 利用催化剂在宏循环化反应中实现高Z异构体选择性.
- 证明该方法在表皮素C和nadomarin A的立体选择性合成中的有效性.
主要成果:
- 基于的催化剂使得高度立体选择性的RCM能够实现,提供高达97%的Z同位素.
- 催化剂是稳定的空气,并允许产品隔离在高产量和立体选择性.
- 该方法成功地促进了表皮素C和纳卡多马林A的立体选择性合成,克服了以前的局限性.
- 有效的RCM和副产品的重新整合导致了优先循环路径.
结论:
- 通过RCM建立了一个可靠和实用的方法,用于通过RCM进行立体选择性宏环基合成.
- 基于的催化剂在控制烯立体化学方面具有显著的优势,特别是在复杂分子中.
- 这种方法为自然产品合成中的晚期RCM提供了强大的解决方案,提高了效率和立体化学结果.
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