一个有机金属Cu20纳米集群:合成,表征,在上固定,和"点击"化学
Andrew W Cook1, Zachary R Jones2, Guang Wu1
1Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States.
Journal of the American Chemical Society
|December 7, 2017
概括
原子精确纳米集群 (APNC) 提供了新的催化可能性. 这项研究引入了一种新的铜APNC,在没有预处理的情况下有效催化"点击"反应,并在支持时表现出增强的稳定性.
科学领域:
- 纳米科学和纳米技术
- 有机金属化学
- 催化剂
背景情况:
- 由有机金属连接体保护的原子精确纳米集群 (APNC) 是纳米科学的一个有希望的领域.
- 预计这些APNC可以避免加热等苛刻的激活方法,这可能会导致烧结.
研究的目的:
- 合成一种新的混合价值有机铜APNC.
- 调查其催化活性,特别是对于"点击"反应.
- 探索合成的APNC的稳定性和固定性.
主要方法:
- 在乙烯的存在下通过降低Cu(OAc) 与Ph2SiH2合成铜APNC [Cu20(CCPh) 12 ((OAc) 6].
- 将集群固定在部分脱氧化上.
- 使用Cu K边缘EXAFS光谱进行了表征.
- 在 [3+2] 循环添加反应中对催化活性进行评估.
主要成果:
- 成功合成混合价值有机金属铜APNC [Cu20 ((CCPh) 12 ((OAc)) ] (1),具有独特的四面体[Cu4]2+核心.
- 集群可以在上固定,释放乙烯.
- 在没有预处理的情况下,无支和支集群都是有效的"点击"反应的催化剂.
- EXAFS分析证实了无支持和支持集群之间的结构相似性,并且在催化后没有显著的变化,表明高稳定性.
结论:
- 一种新的,稳定的铜APNC已经合成和特征.
- APNC是一种有效的,不需要预处理的"点击"反应催化剂.
- 固定增强了集群在反应条件下的稳定性,为实际应用铺平了道路.
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