4 + 3 循环加法反应的不对称器官催化
Michael Harmata1, Sunil K Ghosh, Xuechuan Hong
1Department of Chemistry, University of Missouri-Columbia, Columbia, Missouri 65211, USA. harmatam@missouri.edu
Journal of the American Chemical Society
|February 20, 2003
概括
研究人员开发了4 + 3循环添加的不对称有机催化剂. 基拉尔胺和酸催化了该反应,产生了来自西洛克西丁和二烯的基丰富产物.
科学领域:
- 有机化学 有机化学
- 不对称的合成方法
- 机体催化剂是有机催化剂.
背景情况:
- 4 + 3 循环加法反应是有价值的合成工具.
- 开发不对称的变体对于立体选择合成至关重要.
- 器官催化提供了一种无金属的催化方法.
研究的目的:
- 为4+3循环加法反应开发第一个不对称的有机催化方法.
- 为了实现4+3循环添加产品的酶选择性合成.
- 为了利用性二次胺作为催化剂.
主要方法:
- 4-trialkylsilyloxypentadienals与二烯的反应.
- 使用奇拉二次胺和三酸作为催化系统.
- 使用2,5-二甲基作为二烯成分.
主要成果:
- 形成以反聚物丰富的4 + 3循环添加产品.
- 在2,5-二甲基和4-三甲基西基-2,4-五甲基之间反应中,获得了单个二甲基和89%的反体过量.
- 在循环载荷管道上报告了64%的收益率.
结论:
- 证明了第一个成功的4 + 3循环加法反应的非对称器官催化.
- 建立了复杂循环化合物的酶选择性合成的新方法.
- 突出了在循环添加化学中性氨基催化作用的潜力.
相关概念视频
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