在低催化剂负载下对螺旋活性和螺旋活性进行酶选择合成
Takeru Saito1, Antonio Navarro2, Huw M L Davies1
1Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States.
Journal of the American Chemical Society
|March 5, 2026
概括
这项研究介绍了一种高效的催化方法,用于从二乳和乳中合成螺旋cyclopropanes. 催化过程实现了优异的产量和立体选择性,即使催化剂负载极低.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 药用化学 医学化学
背景情况:
- 螺旋环化合物在药物化学中具有价值.
- 螺旋cyclopropanes的不对称合成是一个未经探索的领域.
- 过渡金属催化提供了一条通往复杂分子架构的途径.
研究的目的:
- 开发使用α-diazo乳和乳的螺旋cyclopropanes的不对称合成.
- 为了探索催化 [2+1] 循环化反应.
- 研究基质结构和反应条件对立体选择性的影响.
主要方法:
- ((II) 催化剂Rh2 ((S-p-PhTPCP) 4) 用于 [2+1] 循环化.
- 3-diazo δ-lactones和乳糖与各种基质发生反应.
- 进行了反应条件的优化,包括温度和二化合物环大小.
主要成果:
- 轻松合成5-oxa和5-azaspiro[2.5]octanones,获得高达98%的产量.
- 高分离选择性 (高达98% ee) 和分离选择性 (高达11:1 d.r.) 观察到的情况.
- 极低的催化剂负荷 (0.00005mol%) 导致了高的营业额 (1.74万).
- 七个成员的二化合物在低温下产生了增强的立体控制 (>30:1 d.r.,99% ee).
结论:
- 开发的方法提供了有效的医疗相关的螺旋cyclopropane支架的访问.
- 实现的催化剂加载和立体控制是不对称催化剂的重大进步.
- 基质环大小和反应温度是控制立体选择性和防止副作用的关键参数.
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