催化N-propargyl酶胺衍生物的循环异构
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
Journal of the American Chemical Society
|May 11, 2006
概括
一个新的催化反应有效地从N-propargyl酶氨酸衍生物中合成六个成员的亚环环. 这种方法采用温和的条件,并为重要的药物和天然产品结构提供了有价值的途径.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 合成方法论 合成方法论
背景情况:
- 在许多天然产品和药品中,单环是关键的结构图案.
- 在药物化学中,高效的合成路径向六个成员的亚循环是非常受欢迎的.
- 目前存在的阿扎环合成方法可能需要恶劣的条件或缺乏广泛的适用性.
研究的目的:
- 开发一种新,温和和高效的催化方法来合成六个成员的环.
- 研究反应机制,包括催化剂,和溶剂的作用.
- 确定这种新方法对于访问有价值的azacycle结构的实用性.
主要方法:
- 开发N-propargyl酶胺衍生物的催化循环异构.
- 反应条件的优化,包括催化剂 ([Rh(C2H2) 2Cl] 2 / P(4-F-C6H4) 3),基 (DABCO) 和溶剂 (DMF).
- 机制研究以阐明反应途径,涉及维尼利丁中间体和质子转移.
主要成果:
- 成功地将N-propargyl酶胺衍生物转化为六个成员的亚环环,产量很好.
- 确定一个有效的催化系统,包括前体,素联体和DABCO基.
- 证明反应通过乙烯中间体和基质介导的质子转移进行,需要近极溶剂.
结论:
- 已经建立了一种新且高效的催化循环异构化,用于六个成员的阿萨基尔合成.
- 反应在温和的条件下进行,为访问复杂的阿扎循环支架提供了一种实用方法.
- 这种方法对合成具有医学意义的化合物和天然产品具有重大潜力.
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