高分离选择性铜 (I) - 硫催化1,3-双极循环添加亚甲化物
Silvia Cabrera1, Ramón Gómez Arrayás, Juan C Carretero
1Departamento de Química Orgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain.
Journal of the American Chemical Society
|November 25, 2005
概括
一种新型的合性易斯酸催化剂有效地驱动不对称的1,3-双极循环添加反应. 这种系统可以实现高产量和异常的enantioselectivity为亚甲化物,即使有ketimine衍生基质.
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:
- 亚甲化物是有机合成中使用的多功能1,3-二极体.
- 催化不对称的1,3-双极循环添加对于创建奇拉分子至关重要.
- 开发这些反应的高效和选择性催化剂仍然是一个关键的挑战.
研究的目的:
- 为不对称的1,3-双极循环添加反应开发一种高效的合性易斯酸催化剂.
- 为了研究这种催化系统的范围和局限性,使用各种亚甲和双极基质.
- 报告第一个成功的催化不对称循环加法,使用胺衍生的亚甲.
主要方法:
- 使用Cu(CH3CN) 4ClO4和平面合P,S-连接物Fesulphos.形成一个催化剂系统.
- 催化剂的应用在1,3-双极循环添加亚甲化物中的应用.
- 对反应产物的产量,二重选择性 (内附性) 和反选择性 (ee%) 的分析.
主要成果:
- 这种Cu (I) -Fesulphos催化剂系统证明了作为一种利的易斯酸的高效率.
- 低催化剂负载 (0.5-3mol%) 是有效的,产生良好的产量内附加物.
- 实现了高达>99% ee的异常反选择性.
- 该程序对亚甲和双极组分具有广泛的结构范围.
- 这项研究成功地证明了第一个催化不对称的循环添加与胺衍生的亚甲.
结论:
- (I) - 硫催化剂系统是用于不对称的1,3-双极循环添加的高度有效的合性易斯酸.
- 这种方法提供了一个强大的工具,用于复杂的性分子的enantioselective合成.
- 凯胺衍生的亚甲的证明效用扩大了催化不对称循环添加的适用性.
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