对立的辅助构造在oxazolidinone导向的纳扎罗夫循环中产生相同的扭矩选择性
Bernard L Flynn1, Narasimhulu Manchala, Elizabeth H Krenske
1Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia. bernard.flynn@monash.edu
Journal of the American Chemical Society
|June 14, 2013
概括
在非对称合成中发现了一种用于奇拉性oxazolidinone辅助剂的新机制,该机制是由性菌株而不是共平面性驱动的. 这种途径在像纳扎罗夫循环化这样的反应中提供了精确的立体控制.
科学领域:
- 有机化学 有机化学
- 不对称的合成方法
- 立体化学是一种立体化学.
背景情况:
- 基拉尔oxazolidinone辅助剂通常通过coplanar形状控制立体化学.
- 在选择性反应的基质的辅助块特定面上的替代物.
研究的目的:
- 为了研究一种使用奇拉性oxazolidinone辅助剂的立体控制的替代机制.
- 探索由性应变驱动的非共平面立体导向.
主要方法:
- 计算研究,特别是密度函数理论 (DFT) 的计算 (M06-2X//B3LYP).
- 在一个不对称的纳扎罗夫循环中分析过渡状态.
主要成果:
- 发现了一种由联应变驱动的立体控制机制,它偏离了共平面模型.
- 基拉尔氧利丁提供完整的扭矩选择性和区域选择性控制.
- 确定了两个类似的能量过渡状态构造 (syn和anti),两者都有利于相同的扭矩选择性.
结论:
- 基菌株是一种可行的替代机制,用于对氧利丁介导反应中的立体控制.
- 这种途径对于传统的共平面范式之外的体阻碍基板是有效的.
- 这些发现扩大了对非对称合成中的立体导向的理解.
相关概念视频
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