通过不对称的C-C激活来简要合成 (-) - 环拉维因和 (-) -5-epi-环拉维因
Lin Deng1, Mengqing Chen1,2, Guangbin Dong1
1Department of Chemistry , University of Chicago , Chicago , Illinois 60637 , United States.
Journal of the American Chemical Society
|July 7, 2018
概括
这项研究提出了使用C-C激活有效合成 (-) - 循环氨酸. 这种新的Rh催化"切割和"方法在短短10个步骤中实现了高反选择性.
科学领域:
- 有机化学 有机化学
- 合成化学 合成化学
- 催化剂是一种催化剂.
背景情况:
- 自然产品合成对于药物发现和理解生物过程至关重要.
- 开发复杂分子的高效和enantioselective合成路径仍然是有机化学的一个重大挑战.
- C-C激活方法为构建复杂的分子架构提供了强大的工具.
研究的目的:
- 为了证明C-C激活策略的合成实用性.
- 为了实现 (-) - 循环氨酸和 (-) -5-epi - 循环氨酸的对抗选择性总合成.
- 开发一种高效且广泛适用的催化系统,用于复杂的天然产品合成.
主要方法:
- 不对称的Rh催化"切割和"转换在子环丁和烯酸之间.
- 帕拉催化联C-N键合/性化用于环丁构造.
- 对于四位置换的环氨酸形成而进行的灾难选择性环氨酸.
主要成果:
- 在10个步骤中实现了 (-) -cycloclavine和 (-) -5-epi-cycloclavine的总合成,总产量为30%.
- 高度反选择的Rh催化碳酸酶化形成了与印度林融合的三环核.
- 改善了"切割和"反应的催化条件,产生了94-99%的反体过量 (即99%的反体过量). ) 的情况.
结论:
- 开发的C-C激活策略对于合成复杂的自然产品非常有效.
- 该方法允许快速访问具有融合和桥梁环系统的分子.
- 这种方法对合成各种天然产品和候选药物具有前景.
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