不受保护的英多尔的同质Pd催化不对称化:范围和机制研究
Ying Duan1, Lu Li, Mu-Wang Chen
1State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences , Dalian 116023, China.
一种新的催化非对称化方法有效地从无保护的高选择性醇中产生奇拉性印度林. 这一突破使生物活性化合物的简单合成成为可能,并为催化过程提供了机理性的见解.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 不对称的合成方法
背景情况:
- 印度是制药和天然产品中至关重要的构建模块.
- 对象不对称的化是具有挑战性的,特别是对于未受保护的基板.
- 开发高效的催化系统用于合性印度林合成是非常理想的.
研究的目的:
- 开发一种高效的催化不对称化无保护的.
- 为了合成具有奇拉性印度林核的生物活性产品.
- 用实验和计算方法阐明反应机制.
主要方法:
- 使用强烈的布伦斯特德酸激活剂,用催化不对称化.
- 同位素标记研究和ESI-HRMS用于识别反应中间体.
- 通过NMR光谱学观察活跃的催化物种.
- 密度函数理论 (DFT) 计算用于机械研究.
主要成果:
- 在化各种未受保护的内醇中达到高的反抗选择性 (高达98% ee).
- 证明了生物相关的合性印度衍生物的容易合成.
- 鉴定出伊米尼盐作为关键中间体,并观察到活性Pd-H物种.
- 提出了一种循序渐进的外球和离子化机制,其中涉及一个双功能Pd催化剂.
结论:
- 开发的方法提供了一条有效的途径,以奇拉的Indolines.
- 反应通过一种独特的离子化机制进行,这种机制由强大的布伦斯特酸和极性溶剂促进.
- 催化剂的双功能性质和结合相互作用对于高反选择性至关重要.
- 该工艺对氧气,酸和水具有耐受性,提高了其实际适用性.
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