内部分子附近挫败的酸/酸路易斯对的碳化反应
Muhammad Sajid1, Arunlibertsen Lawzer, Weishi Dong
1Organisch-Chemisches Institut, Westfälische Wilhelms-Universität , Corrensstraße 40, 48149 Münster, Germany.
Journal of the American Chemical Society
|October 24, 2013
概括
内部分子丧的易斯对 (FLP) 与一氧化碳发生反应. 根据条件,FLP形成异环碳基或碳基,表现出独特的反应性.
科学领域:
- 有机金属化学 有机金属化学
- 主群 化学 化学
- 催化剂是一种催化剂.
背景情况:
- 丧的易斯对 (FLP) 是易斯的酸对,不能形成经典的 adduct.
- 内分子FLP在同一分子中包含易斯酸和基部分.
- FLP与一氧化碳 (CO) 等小分子的反应性是研究的一个关键领域.
研究的目的:
- 研究分子内FLP对一氧化碳的合作添加.
- 探索反应条件 (溶液与矩阵,温度) 对FLP-CO adduct形成的影响.
- 为了研究从其化产品中获得的FLP的气相行为.
主要方法:
- 内分子FLP的合成和表征 (Mes2PCH2CH2B ((C6F5) 2) 和一种基于norbornane的FLP).
- 在不同的条件下,FLP与一氧化碳的反应 (溶液在-35°C,矩阵在25K).
- 密度函数理论 (DFT) 计算以研究反应机制和能量学.
主要成果:
- 内分子FLP Mes2PCH2CH2B(C6F5)2 协同添加CO,形成一个五个成员的异环碳烯化合物.
- 一个基于norbornane的分子内FLP会在溶液中产生一个五个成员的异环FLP-carbonyl化合物.
- 在矩阵隔离条件下,相同的FLP在没有素参与的情况下选择性地形成碳.
- DFT研究表明,在溶液中形成一种基酸zwitterion的exergonic形成,这种溶液在气相中倾向于失去H2.
结论:
- 内部分子FLP对一氧化碳表现出不同的反应性,根据反应环境形成不同的异环或碳酸产物.
- 内部分子FLP的近距离和框架显著影响CO激活通路.
- 从FLP衍生的物种的稳定性和行为在溶液和气相之间可以显著不同.
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