在dibenz[a,c]anthracene边缘的Pt和Pd1,4位移
1Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA.
Journal of the American Chemical Society
|May 4, 2006
概括
用二[a,c]烯联体加热和复合物会诱导与碳结合的金属发生1,4位移. 这种反应对于来说更快,涉及极性中间体,避免酸性路径.
科学领域:
- 有机金属化学 有机金属化学
- 协调化学 协调化学
- 有机合成 有机合成
背景情况:
- 含有多环芳 (PAH) 的有机金属复合物在催化和材料科学中至关重要.
- 了解这些系统中的联体动力学和金属迁移是控制反应性的关键.
- 和复合物与联体提供可调节的电子和硬质性质.
研究的目的:
- 为了研究含有二[a,c]炭连接体的特定和复合物的热行为.
- 阐明这些有机金属化合物中的金属迁移机制.
- 为了比较与复合物的反应性和稳定性.
主要方法:
- 合成和特征的转 (dibenz[a,c]-9-yl) bis (triethylphosphine) 及其类型.
- 在不同条件下对溶液中的复合物进行热分析.
- 用光谱学研究来监测反应的进展,并识别中间体.
- 标记实验用于探测反应机制.
主要成果:
- 在加热跨异构体时,观察到与碳结合的金属 (或) 的1.4位移.
- 与复合体相比,复合体的观察到的金属转移明显更快.
- 反应通过极性中间体进行,这是溶剂效应所暗示的.
- 在D2O的存在下没有加入,表明中间体不是酸性的.
结论:
- 这项研究表明,在有机金属复合物中,具有二[a,c]甲烯配体的新型热1,4-金属转移.
- 观察到的反应性突出显示了和在这种特定转化过程中的差异.
- 机械学的洞察力表明,涉及极性中间体的非酸性途径与设计新催化系统相关.
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