基拉尔双循环瓜尼丁催化了人类的反选择性反应
Juan Shen1, Thanh Truc Nguyen, Yong-Peng Goh
1Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543.
Journal of the American Chemical Society
|October 19, 2006
概括
一种新型的性双循环guanidine催化剂有效地促进了anthrones和dienophiles之间的反应. 这种突破性的方法在迪尔斯-阿尔德和迈克尔反应中实现了高产量和酶选择性.
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:
- 人类是有机合成中的多功能构建块.
- 开发用于安特龙功能化的enantioselective催化方法至关重要.
- 基质催化迪尔斯-阿尔德反应往往缺乏高的酶选择性.
研究的目的:
- 为了开发一个高度enantioselective催化剂的反应涉及anthrones.
- 为了探索在不对称催化过程中奇拉双循环guanidines的实用性.
- 调查开发的催化系统的范围和局限性.
主要方法:
- 查合双循环瓜尼丁催化剂对安龙 - 迪诺菲尔反应的检测.
- 优化反应条件,包括溶剂和温度.
- 使用光谱方法 (NMR,MS) 进行反应产物的表征.
- 使用奇拉色谱测定等离子过量 (ee).
主要成果:
- 基拉尔双循环瓜尼丁1显示出优异的催化活性.
- 催化剂有效地调解了迪尔斯-阿尔德和迈克尔反应.
- 对于各种安龙衍生物和二烯类植物,获得了高产量,区域选择性和反选择性.
- 这代表了第一个高度反选择的基质催化Anthrone Diels-Alder反应.
结论:
- 基拉尔双循环guanidine 1 是一个高效的催化剂,用于 enantioselective anthrone 功能化.
- 开发的方法提供了与高立体化学控制有价值的性 adducts的访问.
- 这项工作为利用人类脚手架进行不对称合成开辟了新的途径.
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