Department of Advanced Materials Chemistry, Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan.
Dalton Trans. 2018 Jun 19;47(24):8003-8012. doi: 10.1039/c8dt01295d.
In this work, three different types of acetylacetonato-based pincer-type nickel(ii) complexes (2) were prepared. Complex 2a possessed the tridentate ONN ligand, which was constructed by the condensation reaction of acetylacetone with N,N-diethylethylenediamine. Complex 2b contained the PPh2 donor group in contrast to the NEt2 group in 2a, i.e., an ONP ligand framework. Complex 2c was composed of the NNN ligand, which was prepared by the reaction of 4-((2,4,6-trimethylphenyl)amino)pent-3-en-2-one with N,N-diethylethylenediamine. In addition to X-ray diffraction analysis, these complexes were characterized spectroscopically. Their catalytic activity for a cross-coupling reaction of aryl halides with aryl Grignard reagents was also evaluated. Among these complexes, 2b acted as an effective catalyst for the cross-coupling reaction using aryl chlorides as electrophiles. The electronic properties of these Ni(ii) complexes were investigated by cyclic voltammetry and density functional theory calculations.
在这项工作中，制备了三种不同类型的基于乙酰丙酮的钳式镍（ii）配合物（2）。配合物 2a 具有三齿 ONN 配体，它是由乙酰丙酮与 N,N-二乙基亚乙基二胺的缩合反应构建的。与 2a 中的 NEt2 基团相比，配合物 2b 含有 PPh2 供体基团，即 ONP 配体骨架。配合物 2c 由 NNN 配体组成，它是由 4-((2,4,6-三甲基苯基)氨基)戊-3-烯-2-酮与 N,N-二乙基亚乙基二胺反应制备的。除了 X 射线衍射分析外，还对这些配合物进行了光谱表征。还评估了它们对芳基卤化物与芳基格氏试剂的交叉偶联反应的催化活性。在这些配合物中，2b 作为使用芳基氯作为亲电试剂的交叉偶联反应的有效催化剂。通过循环伏安法和密度泛函理论计算研究了这些 Ni(ii)配合物的电子性质。
