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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
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遥远的基组切换选择性:四环环形螺旋醇的二聚异合成
Jun Zhu1, Yong Liang, Lijia Wang
1State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China.
Journal of the American Chemical Society
|April 29, 2014
概括
用四元立体中心合成复杂分子是具有挑战性的. 这项研究引入了一种催化反应,以产生四环螺旋,通过基和计算分析控制立体化学.
科学领域:
- 有机合成 有机合成
- 立体选择性合成 立体选择性合成
- 催化剂是一种催化剂.
背景情况:
- 在复杂有机分子的合成中实现立体控制,特别是那些含有全碳四元立体中心的分子,在合成化学中构成了重大障碍.
- 四级立体中心在许多天然产品和药品中普遍存在,使其高效的构造成为一个关键目标.
研究的目的:
- 开发一种新型的合成方法来构建四环环-合螺旋胺骨.
- 为了在这些复杂的螺旋胺结构的cis-和trans-异构体的形成中实现高的二聚体选择性.
- 阐明在报道的取消反应中立体控制的机械起源.
主要方法:
- 铜 (II) 催化在捐赠体-接受体环烯和醇之间发生的分子内 [3 + 2] 无效反应.
- 在循环前体上远程基的系统变化,以影响二选择性.
- 密度函数理论 (DFT) 计算,以调查调整立体化学结果的过渡状态和非共价相互作用.
主要成果:
- 成功合成了四环环旋旋-合的高效率的螺旋林支架.
- 通过修改环烯的替代剂,有能力选择性地产生cis或trans-diastereomers.
- DFT计算显示,有吸引力的雌激素-烯相互作用有利于转异构体形成,而固体排斥有利于异构体形成.
结论:
- 开发的Cu(II) 催化无效化为复杂的螺旋胺结构提供了一条多功能途径.
- 立体化学结果可以通过循环基质的合理设计进行调整,以计算洞察为指导.
- 这项工作为具有具有挑战性的四级立体中心的分子的立体选择性合成提供了有价值的策略.
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