不对称的有机催化1,3-二极循环添加亚甲化物与β替代的循环子
Han Zhong1, Xiao-Yi Zhang1, Yong-Mou Yao1
1The Fifth Affiliated Hospital and Key Laboratory of Molecular Target & Clinical Pharmacology, School of Pharmaceutical Sciences, Guangzhou Medical University, Xinzao, Panyu District, Guangzhou 511436, China.
The Journal of organic chemistry
|July 1, 2024
概括
这项研究引入了一种新的方法,用于控制1,3-双极循环添加反应中的立体化学. 它可以合成具有高反选择性和异选择性复杂的合性他衍生物.
科学领域:
- 有机化学 有机化学
- 不对称的合成方法
- 催化剂是一种催化剂.
背景情况:
- 1,3-双极循环添加反应对于形成五个成员的异态循环至关重要.
- 控制这些反应中的立体化学,特别是循环子,仍然是一个挑战.
- 开发高效的催化系统,以进行酶选择性和二聚选择性合成是非常可取的.
研究的目的:
- 开发一种用于对1,3-双极循环添加反应进行异构选择和异构选择控制的方法.
- 合成的四基罗[2,1-a]他氨酸和六基胺[1,2-a]他氨酸-10(8H) -一个衍生物.
- 探索不同添加剂对反应结果和立体控制的影响.
主要方法:
- 使用的甲二甲化物作为1,3-二极体.
- 采用β-置换的循环子作为双极性物.
- 研究了使用基于辛可纳的初级氨基 (C3) 和奇拉尔坎佛硫酸的维尼洛基离子激活.
- 通过较弱的3,5-bis(trifluoromethyl) 酸添加剂探索了内分离胺激活.
主要成果:
- 获得了奇拉四二二[2,1-a]甲衍生物 (3) 的选择性和选择性合成.
- 获得了具有优良立体控制的合性六化[1,2-a]甲-108H) -one衍生物 (4).
- 证明了不同酸性添加剂在指导反应路径和立体化学结果方面的独特作用.
结论:
- 开发了一种用于立体控制的1,3-双极循环添加的多功能催化系统.
- 成功合成了具有高选择性的有价值的合性甲衍生物.
- 强调了催化剂和添加剂选择在实现所需立体化学结果方面的重要性.
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