一个平面的尼克拉斯皮罗潘坦复合物与基于的金属:合成,结构和协同的二激活
Yanping Cai1, Shengjie Jiang1, Thayalan Rajeshkumar2
1Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou215123, P. R. China.
Journal of the American Chemical Society
|August 30, 2022
概括
这项研究揭示了一种新的平面- bis-cyclopropane复合物与联体,挑战了传统的结合理论. 这种复合物通过独特的Mg/Ni合作机制激活,并催化化反应.
科学领域:
- 有机金属化学
- 协调化学
- 催化剂
背景情况:
- 德瓦-查特-肯森模型描述过渡金属-烯酸结合为π-复合物和金属环之间的连续性.
- 教科书规则预测晚期过渡金属乙烯复合物比金属cyclopropanes更有利于π-复合物的形成.
研究的目的:
- 合成和描述一种新型的低旋转过渡金属双乙烯复合物.
- 调查由此产生的异金属复合物的结合性和反应性.
- 探索激活和催化活动的机制.
主要方法:
- 使用基金属连体和基2合成异金属复合物 (LMg) 2Ni ((C2H4) 2).
- 使用X射线衍射和光谱方法进行结构性表征.
- 使用密度函数理论 (DFT) 阐明结合和反应机制的计算研究.
- 用各种不和基质进行化催化实验.
主要成果:
- 形成一个前所未有的平面金属-bis-cyclopropane结构, 确定为一个nickellaspiropentane.
- 在中心观察线性Mg-Ni-Mg连接和平面协调几何.
- 在暴露于H2时转化为四桥复合物 (LMg) 2Ni
- 在不经金属氧化的情况下化一种新的Mg/Ni合作H2激活机制.
- 在温和条件下对各种不和基质的化具有催化活性.
结论:
- 合成的复合物代表了平面金属cyclopropane的一个罕见的例子,挑战了已建立的结合范式.
- 对于H2激活的Mg/Ni合作机制为催化中的金属-合作提供了新的视角.
- 异金属复合物显示出作为化反应的催化剂的显著潜力.
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