催化C-C σ-键的不对称失能,由环应变的酸盐复合物实现
Hong-Cheng Shen1, Mihai V Popescu2, Ze-Shu Wang1
1School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, U.K.
Journal of the American Chemical Society
|July 20, 2023
概括
这项研究引入了一种催化方法,用于使用双环[1.1.0]丁 (BCB) 复合物的C-C键的非对称功能化. 这种新型反应产生具有独特的抗添加二选择性的.
科学领域:
- 有机化学
- 催化剂
- 合成方法
背景情况:
- 有机化合物是有机合成和药物发现中的关键中间体.
- 基酸盐的反选择性1,2-金属酸盐重组提供了一条通往有价值的奇拉试剂的途径.
- 在合成化学中,C-C键的不对称功能化仍然是一个重大挑战.
研究的目的:
- 开发一种新的催化不对称的1,2-金属酸诱导的双环[1.1.0] (BCB) 酸复合体.
- 为了实现C-C西格玛键的不对称功能化,包括脱碳和碳化.
- 合成富含的三维1,1,3-三替代循环产品.
主要方法:
- 催化不对称的1,2-金属酸诱导的重组.
- 在双环[1.1.0] (BCB) 复合物中利用应变释放.
- 使用实验数据和密度函数理论 (DFT) 计算来获得机械洞察力.
主要成果:
- 一个成功的C-C西格玛键的不对称功能.
- 获取各种1,1,3替代的酸产品,其中含有酸.
- 通过*anti*-addition获得的*trans* diastereoisomers的观察,与之前的*syn*-addition路径形成对比.
结论:
- 开发的协议提供了一种新且高效的合成复杂的奇拉环结构的方法.
- 观察到的*反*添加二重选择性归因于BCB酸复合物和早期过渡状态的高核友性.
- 这项工作扩大了不对称的功能化范围,并为进一步的合成应用提供了有价值的基石.
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