- 对称的迪尼克尔催化剂对抗选择性 [4 + 1] - 循环添加剂
Michael J Behlen1, Christopher Uyeda1
1Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States.
Journal of the American Chemical Society
|September 25, 2020
概括
迪尼克尔催化剂使不对称的 [4 + 1] 环添加成为可能,产生具有高Z-选择性的甲基烯cyclopentenes. 这种方法是立体融合的,允许混合E/Z-dienes以实现高效的合成.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 不对称的合成方法
背景情况:
- 酶选择性循环添加对于合成性分子至关重要.
- 为复杂的有机转化开发高效的催化剂仍然是一个关键的挑战.
研究的目的:
- 开发用于反选择性分子间 [4 + 1] - 循环添加的新型二基催化剂.
- 为了研究反应与E/Z-diene混合物的立体融合性质.
- 用计算方法阐明不对称感应的机制.
主要方法:
- 作为催化剂,使用了迪尼克尔纳夫提里丁-比斯 (Oxazoline) 复合物.
- 在vinylidene等价物和1,3-dienes之间进行了分子间的 [4 + 1] - 循环添加.
- 分析产品的立体化学和酶选择性 (ee值).
- 用密度函数理论 (DFT) 来进行机械学研究.
主要成果:
- 在甲基烯cyclopentenes的形成中达到高的enantioselectivity.
- 证明了对外环烯的高Z选择性.
- 观察到对E-和Z-二烯的立体融合反应途径.
- 确定可以使用E/Z-diene混合物,产生具有一致立体化学和ee的产品.
结论:
- 迪尼克尔催化剂有效地促进了反选择性 [4 + 1] 循环添加.
- 反应的立体融合性质简化了基质要求.
- DFT建模为催化剂的不对称感应机制提供了洞察力.
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