纳扎罗夫反应:电循环和并行运动分辨率的中继策略
Xuelong Qiao1, Jiwei Xu1, Haibing He1
1Shanghai Key Laboratory of Green Chemistry and Chemical Processes, State Key Laboratory of Petroleum Molecular & Process Engineering, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200050, China.
Organic letters
|December 6, 2024
概括
这项研究引入了一个enantioselective光诱导纳扎罗夫反应. 一个合性尿素配体使并行运动分辨率成为可能,在合的三环产物形成中实现了高立体选择性.
科学领域:
- 有机化学 有机化学
- 不对称的合成方法
- 摄影化学的使用.
背景情况:
- 纳扎罗夫反应是合成环丁的重要工具.
- 在光诱导的纳扎罗夫反应中实现抗选择性仍然具有挑战性.
- 结合不同反应类型的中继策略提供了潜在的解决方案.
研究的目的:
- 使用继电器策略开发一种对抗选择性的光诱导纳扎罗夫反应.
- 为了研究平行动力分辨率 (PKR) 诱导反选择性的有效性.
- 合成 cis-6,5,6-fused 三环化合物,具有高反体过量 (ee).
主要方法:
- 一个两步的继电策略,涉及电循环,其次是PKR.
- 使用双功能性性尿素连接体用于去质子化步骤.
- 采用一种性N,N-二甲基氨基基基因组来控制区域选择性.
主要成果:
- 在最初的电循环化步骤中没有观察到酶选择性.
- 在去质子化步骤中的并行动态分辨率 (PKR) 成功诱导了enantioselectivity.
- 区域选择性去质子化产生了 cis-6,5,6-融合的三环类立体异构体,具有高的 ee 和产量.
结论:
- 开发的中继策略对于对抗选择性纳扎罗夫反应是有效的.
- 基拉尔尿素配体对于通过PKR实现高立体控制至关重要.
- 这种方法为复杂的性三环结构提供了可行的途径.
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