关于纳扎罗夫循环/瓦格纳-梅尔维恩重排序序的实验和理论研究
David Lebœuf1, Vincent Gandon, Jennifer Ciesielski
1Department of Chemistry, University of Rochester, Rochester, New York 14627, USA.
Journal of the American Chemical Society
|April 5, 2012
概括
一个新的铜 (II) 中介反应序列有效地从二维尼尔基中合成高度功能化的环二烯. 这种方法可以创建立体中心,并且可以通过使用特定的铜复合体来优化高 diastereoselectivity.
科学领域:
- 有机化学 有机化学
- 合成方法论 合成方法论
- 催化剂是一种催化剂.
背景情况:
- 环丁是有价值的合成中间体.
- 目前用于合成环丁的方法在范围和立体控制方面存在局限性.
- 纳扎罗夫和瓦格纳-梅尔维恩重组是重要的碳-碳键形成反应.
研究的目的:
- 开发一种化学选择性铜 (II) 介导的重排序序,用于合成高度功能化的环丁.
- 为了研究这种反应的基质范围,局限性和立体化学结果.
- 阐明反应机制,包括铜的作用 (II) 和潜在的异构化.
主要方法:
- 化学选择性铜 (II) 介导的纳扎罗夫/瓦格纳-梅尔韦恩二维尼尔基的重新排列.
- 基质结构的系统变化,以确定范围和限制.
- 使用Cu (II) - 比索克萨林复合物来控制立体化学.
- 密度函数理论 (DFT) 计算以建模反应机制.
主要成果:
- 反应序列成功生成高度功能化的环烯.
- 连续的[1,2]-shifts的选择性取决于迁徙能力或硬质体质量.
- 该方法允许创建邻近的立体中心,包括相邻的四级中心.
- 子部分的E/Z异构化可以在循环化之前发生,从而产生二聚体混合物.
- (II) - 比索克萨林复合物防止异体化,并产生高的异体选择性.
- DFT的计算支持所提出的反应路径和立体化学观测.
结论:
- 已经建立了一个强大而通用的铜 (II) 介导合成路径到功能化的环丁.
- 这种反应对立体化学有很好的控制,特别是在使用性铜复合物时.
- 这种方法为构建具有多个立体中心的复杂分子架构提供了强大的工具.
相关概念视频
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