单原子异质催化剂的体诱导激活用于交叉合反应
Dario Poier1, Oliver Loveday2,3, Marc Eduard Usteri4
1Institute of Chemical Technology, Haute École d'Ingénierie et d'Architecture Fribourg, HES-SO University of Applied Sciences and Arts Western Switzerland, 1700 Fribourg, Switzerland.
干对单原子催化剂 (SAC) 在交叉合反应中至关重要,显著提高了活性. 连接物选择,而不是电子,通过平衡金属中心的可访问性和稳定性来决定性能.
科学领域:
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
- 有机化学 有机化学
背景情况:
- 单原子催化剂 (SAC) 为精细化学合成提供了同质催化剂的可回收替代品.
- 体通常需要SACs,但它们在基于的SACs (Pd-SACs) 中的作用不明.
- 对Pd-SACs的配体的优化在很大程度上被忽视了.
研究的目的:
- 为了研究各种素连接体对单原子催化剂的性能的影响,这些催化剂在Sonogashira-Hagihara (SH) 交叉合反应中支持添加碳 (Pd1@NC).
- 阐明Pd-SACs中控制联结体效应的基本机制.
- 通过合理的连接体设计,为优化Pd-SACs提供见解.
主要方法:
- 利用X射线吸收光谱学 (XAS) 来描述催化剂的电子和结构性质.
- 采用密度函数理论 (DFT) 模拟来合理化实验观测和探索反应机制.
- 在Sonogashira-Hagihara反应中合成并测试了各种联体修饰的Pd-SAC.
主要成果:
- 无干Pd-SACs显示出有限的活性,而干辅助系统显示出显著增强的SH反应性能,活性高达8个数量级.
- 催化剂性能与连接物特性 (如自由连接物体体积和连接物类) 相相关,而不是电子效应.
- 性能是通过在协调和触媒部位对试剂的可访问性时的联结体变形能之间的平衡来确定的.
结论:
- 氨酸配体对于激活Pd-SAC和增强它们在交叉合反应中的催化活性至关重要.
- 配体选择应优先考虑固态因素和协调行为,而不是电子效应,以获得最佳的Pd-SAC性能.
- 这些发现为设计和优化配体修饰的Pd-SACs提供了一个框架,以实现高效的精细化学合成.
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