从未激活的终端基和酸来源获得罗利丁的Rh(III) 催化形式 [4+1] 方法
Sumin Lee1, Honghui Lei1, Tomislav Rovis1
1Department of Chemistry , Columbia University , New York , New York 10027 , United States.
Journal of the American Chemical Society
|August 6, 2019
概括
一种新的Rh(III) 催化方法使得使用简单基的pyrrolidines的合成成为可能. 这种 [4+1] 循环添加有效地创建了具有高 diastereoselectivity 的复杂的螺旋-pyrrolidine 结构.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 合成方法论 合成方法论
背景情况:
- 罗利丁是许多天然产品和药品中发现的至关重要的异环基因.
- 在有机合成中,高效和分类选择性合成路径以取代罗利丁,特别是螺旋罗利丁,仍然是一个重大挑战.
研究的目的:
- 开发一种新且高效的正式 [4+1] 循环添加法,用于合成罗利丁.
- 为了从易于获得的原材料中实现螺旋-罗利丁衍生物的二元选择性构造.
主要方法:
- 使用Rh(III) 催化分子间亚齐里丁化,将未被激活的终端基与4碳合作伙伴结合在一起.
- 采用一种酸促进的环膨胀机制来形成罗利丁环.
主要成果:
- 展示了一种快速和多用途的方法,用于构建各种含罗利丁的化合物.
- 实现了螺旋-罗利丁结构的高度二聚体选择性合成.
- 阐明了涉及亚齐里迪纳和随后环膨胀的反应机制.
结论:
- 开发的正式 [4+1] 方法为罗利丁合成提供了一个强大的新策略.
- 这种方法可以有效地访问有价值的螺旋-罗利丁支架,并具有出色的立体控制.
- 机械学的见解为进一步优化和应用这种催化系统铺平了道路.
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