通过素桥接Pt (I) -Pt (I) 复合体轻松激活二
Piero Mastrorilli1, Mario Latronico, Vito Gallo
1Dipartimento di Ingegneria delle Acque e di Chimica del Politecnico di Bari, Via Orabona 4, I-70125 Bari, Italy. p.mastrorilli@poliba.it
Journal of the American Chemical Society
|March 13, 2010
概括
这项研究揭示了一种新的 (((I) 复合物,通过独特的异解途径可逆地结合. 该研究详细介绍了添加和随后异构化的机制,并提供了对介导的H2激活的见解.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
背景情况:
- 复合物在催化过程中至关重要.
- 了解H2激活机制是开发新催化过程的关键.
- 双核复合体表现出独特的反应性.
研究的目的:
- 为了研究可逆添加H2到一个phosphinito-bridged Pt(I) 复合体.
- 阐明H2激活和随后的异构化反应的机制.
- 探索DFT计算和NMR光谱在理解这些过程中的作用.
主要方法:
- 复合物的合成和表征.
- 在环境条件下进行可逆H2添加实验.
- 密度函数理论 (DFT) 的计算.
- 核磁共振 (NMR) 光谱学.核磁共振 (NMR) 光谱学.
主要成果:
- Pt(I) 复合体 (1) 可逆添加 H2 形成一个 cis-二化物复合体 (2).
- 复合物2异构化为一个更稳定的转二化物异构体 (3).
- DFT计算揭示了一种异质H2分裂路径,涉及酸氧和一个可变的中间体 (D).
- 一个非经典的二复合物 (4) 被确定为脱和交换过程中的中间体.
- 2到3的异构化通过一种涉及Pt-Pt键和桥裂变的分子内机制进行.
结论:
- 氨酸桥接Pt(I) 复合体通过异溶性通路表现出容易和可逆的H2激活.
- 该研究提供了对H2添加,异构化和二核系统中的脱的详细机制理解.
- 这项工作为金属复合体对H2激活的基本知识做出了贡献,并对催化产生了影响.
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