Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
Dalton Trans. 2011 Dec 28;40(48):12856-65. doi: 10.1039/c1dt11079a. Epub 2011 Oct 24.
The 2-(N-alkylcarboxamide)-6-iminopyridine ligands (L1-L7) can bind as either mono-anionic tridentate N^N^N ligands on reaction with PdCl(2)(CH(3)CN)(2), to form complexes LPdCl (C1-C7), or as neutral tridentate N^N^O ligands with NiCl(2)·6H(2)O, to produce complexes LNiCl(2) (C8-C14). All metal complexes were characterized by IR spectroscopy and elemental analysis, and in the case of the palladium complexes, by (1)H and (13)C NMR spectroscopy. The crystal structures of C3, C4, C6, C10, and C12 were determined by X-ray crystallography, and revealed a distorted square geometry around the palladium centre, whereas for nickel, a distorted square-pyramidal geometry was adopted. The representative palladium complex (C3) was further reacted with AgBF(4) in acetonitrile affording the salt [L3Pd(CH(3)CN)][BF(4)] (C15) and the structure of this was confirmed by single-crystal X-ray diffraction. By contrast, carrying out the reaction in dichloromethane rather than acetonitrile, in the presence of malononitrile (CNCH(2)CN), resulted in the formation of the bimetallic palladium complex [L3Pd(CNCH(2)CN)PdL3]·2[BF(4)] (C16). Upon activation with diethylaluminium chloride, all the nickel complexes showed high activity for ethylene dimerization. Furthermore, the palladium complexes exhibited good activities in the vinyl-polymerization of norbornene upon activation with MAO.
2-(N-烷酰胺基)-6-亚氨基吡啶配体（L1-L7）与 PdCl2(CH3CN)2 反应时，可以作为单阴离子三齿 N^N^N 配体结合，形成配合物 LPdCl（C1-C7），或者与 NiCl2·6H2O 作为中性三齿 N^N^O 配体结合，生成配合物 LNiCl2（C8-C14）。所有金属配合物均通过红外光谱和元素分析进行了表征，对于钯配合物，还通过 1H 和 13C NMR 光谱进行了表征。C3、C4、C6、C10 和 C12 的晶体结构通过 X 射线晶体学确定，结果表明钯中心周围存在扭曲的正方形几何形状，而对于镍，则采用扭曲的正方形-金字塔几何形状。代表性钯配合物（C3）进一步与 AgBF4 在乙腈中反应，生成盐 [L3Pd(CH3CN)][BF4]（C15），并通过单晶 X 射线衍射证实了其结构。相比之下，在二氯甲烷中而不是在乙腈中进行反应，并且存在丙二腈（CNCH2CN）时，会形成双金属钯配合物 [L3Pd(CNCH2CN)PdL3]·2[BF4]（C16）。用二乙基铝氯化物活化后，所有镍配合物在乙烯二聚反应中均表现出高活性。此外，钯配合物在 MAO 活化下，对降冰片烯的乙烯基聚合表现出良好的活性。
