从Si (II) 到Si (IV) 和反向:可逆的内分子碳-碳键激活由一个环形Iminosilylene
Daniel Wendel1, Amelie Porzelt1, Fabian A D Herz1
1WACKER-Chair of Macromolecular Chemistry, ∥WACKER-Institute of Silicon Chemistry, ‡Catalysis Research Center, Technische Universität München , Lichtenbergstraße 4, 85748 Garching bei München, Germany.
Journal of the American Chemical Society
|June 8, 2017
概括
这项研究报告了一种新化合物,可以在Si(II) 和Si(IV) 状态之间进行可逆转变. 这种可逆性使得二氧化碳和等小分子的激活成为可能,
科学领域:
- 有机化学
- 主要组化学
- 催化剂
背景情况:
- 在催化过程中,可逆性至关重要,特别是对于低价值化合物.
- 氧化添加和还原消除的相互作用是主要组化学中的催化循环的关键.
研究的目的:
- 报告一种新型的非循环性 iminosilylsilylene (Si(II)) 在C=C键中进行分子内插入.
- 为了研究由此产生的Si(IV) 化合物的可逆性.
- 探索西莱作为小分子激活的合成对应物的实用性.
主要方法:
- 氨基和其衍生物的合成和表征.
- 紫外线光谱研究热可逆性.
- 密度函数理论 (DFT) 的计算.
- 与小分子 (CO2,C2H4,H2) 的反应.
主要成果:
- 通过分子内C=C插入,合成了一种非循环的iminosilylsilylene (1),并很容易形成一个silepine (2).
- (IV) 丝 (2) 呈现易于回归 (II) 的热转化,通过UV-VIS,DFT和烯-添加物的分离得到证实 (3).
- 西莱 (2) 激活了二氧化碳,形成了第一个单质四坐标碳酸复合物 (4).
- 与乙烯和的反应分别产生了西里 (5) 和Si (IV) 二化物 (6).
结论:
- 报告的化合物表现出可逆的Si (II) /Si (IV) 行为,对于催化应用至关重要.
- 在温和的条件下,西莱可以作为一种多功能合成对应物来激活小分子.
- 这项工作扩大了低价值化学和小分子激活的范围.
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