具有环扩展NHC和它们的和复合体的新型皮里丁二碳二烯钉联体
Evangelos Papangelis1, Katrin Pelzer2, Christophe Gourlaouen3
1Inorganic Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771, Athens, Greece.
Chemistry, an Asian journal
|April 15, 2024
概括
采用四胺翅膀尖的新链体被合成并协调到和. 这些复合物在乙烯寡合和聚合过程中表现出中度的催化活性.
科学领域:
- 有机金属化学 有机金属化学
- 协调化学 协调化学
- 催化剂是一种催化剂.
背景情况:
- 开发新的子配体对于推进协调化学和催化是至关重要的.
- N - 异环碳素 (NHC) 器联体的固体和电子特性影响金属中心协调和反应性.
- 了解合体中的结构-活性关系是设计高效催化剂的关键.
研究的目的:
- 通过使用新的CNC连接物合成和表征 (II) 和 (III) 的新复合物.
- 研究这些新型复合物的协调几何,电子特性和催化活性.
- 探索连接体结构对金属中心性能和催化性能的影响.
主要方法:
- 从其前体中生成CNC联体的现场生成.
- 通过与金属前体的反应合成 (II) 和 (III) 具复合体.
- 使用光谱方法和X射线晶体学进行表征 (由几何学讨论暗示).
- 计算研究分析协调几何学和电子性质.
- 使用MAO联合催化剂进行乙烯氧化和聚合的催化试验.
主要成果:
- 通过CNC连接物成功合成了Ni (II) 和Cr (III) 具复合物.
- (II) 复合体表现出四面体扭曲的正方形平面几何和单元基态,归因于连接体的硬性约束.
- 计算分析显示,几何和单元-三元能量依赖于N替代物大小,与伊米达佐林-2-伊利丁类同类相反.
- 可能通过从CrII前体的氧化而形成的CrIII复合物.
- 尼 (II) /MAO和Cr (III) /MAO系统都表现出适度的乙烯氧化和聚合的催化活性.
结论:
- 这种新型的CNC子连接物有效地协调到Ni (II) 和Cr (III) 金属中心.
- 带结构显著影响金属复合物的协调几何学和电子性质.
- 合成的器复合体显示出作为氨酸转换的催化剂的潜力.
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