催化二醇的循环异构化
Barry M Trost1, Michael T Rudd
1Department of Chemistry, Stanford University, Stanford, CA 94305, USA. bmtrost@stanford.edu
Journal of the American Chemical Society
|March 31, 2005
概括
一种新型的循环异构化反应有效地使用催化剂将各种二醇转化为二醇和二醇. 这种方法可以合成五个和六个成员的环,主要的二醇也经历了复杂分子合成的水化循环.
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:
- 二醇是有机合成中的多功能前体.
- 开发有效的催化方法用于二醇转换对于构建复杂的分子架构至关重要.
- 循环异构反应为各种循环化合物提供了途径.
研究的目的:
- 调查各种二醇的循环异构,包括三级,二级和初级的propargylic酒精.
- 使用特定的催化剂探索五和六个环的形成.
- 证明这种方法的合成实用性,特别是对于初级二醇.
主要方法:
- 在循环异构反应中使用一种催化量[CpRu(CH3CN) ]3]PF6.
- 在催化条件下反应三级,二级和初级二醇.
- 分析由此产生的二烯和二烯的结构和立体化学特征.
主要成果:
- 广泛的二醇成功循环异构,形成二和二.
- 该方法允许形成五个和六个成员的环.
- 二级二醇产生单个几何同位素,而初级二醇经历了循环化和水性循环化.
- 实用性在 (+) - α-酸的合成中得到证明.
结论:
- 催化二醇的循环异构化是合成二醇和二醇的有效方法.
- 这种反应可以访问各种循环结构,并控制环形大小和立体化学.
- 对于初级二醇的应用,包括水化循环,扩大了其合成范围,如凯氨酸合成所证明的那样.
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