Li Ji-Kun, Huang Xian-Qiang, Yang Song, Ma Hong-Wei, Chi Ying-Nan, Hu Chang-Wen
Key Laboratory of Cluster Science Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic, School of Chemistry, Beijing Institute of Technology , Beijing 100081, P.R. China.
Inorg Chem. 2015 Feb 16;54(4):1454-61. doi: 10.1021/ic502447b. Epub 2015 Feb 4.
Four alkoxohexavanadate-based Pd-POVs [Pd(dpa)(acac)]2[V6O13(OMe)6] (1), [Pd(dpa)(acac)]2[V6O11(OMe)8] (2), [Pd(dpa)(acac)]2[V6O11(OMe)8]·H2O (3), and [Pd(DMAP)2(acac)]2[V6O11(OMe)8]·H2O (4) (POV = polyoxovanadate; dpa = 2,2'-dipyridine amine; DMAP = 4-dimethylaminopyridine; acac = acetylacetone anion) have been synthesized and fully characterized by single crystal X-ray diffraction and powder X-ray diffraction analyses, Fourier transform infrared spectroscopy, element analyses, and X-ray photoelectron spectroscopy. In 1-4, Pd complexes and hexavanadate anions are assembled through electrostatic interactions. Interestingly, the V6O11(OMe)8 cores in 2 and 3 are a pair of isomers that can be isolated by controlling crystallization temperature. Moreover, to the best of our knowledge, the {V6} core in 3 represents a new octamethoxyhexavanadates cluster. It is notable that compounds 1-4 exhibit excellent heterogeneous catalytic performance in the oxidation of benzyl-alkanes with t-butylhydroperoxide as oxidant. Among them, the catalytic activity of 1 (conv. and selec. up to 99%, respectively) outperforms others and can be reused without losing its activity.
已合成了四种基于烷氧基六钒酸盐的钯 - 多钒酸盐配合物[Pd(dpa)(acac)]2[V6O13(OMe)6] (1)、[Pd(dpa)(acac)]2[V6O11(OMe)8] (2)、[Pd(dpa)(acac)]2[V6O11(OMe)8]·H2O (3) 和 [Pd(DMAP)2(acac)]2[V6O11(OMe)8]·H2O (4)（POV = 多钒酸盐；dpa = 2,2'-联吡啶胺；DMAP = 4-二甲基氨基吡啶；acac = 乙酰丙酮阴离子），并通过单晶X射线衍射和粉末X射线衍射分析、傅里叶变换红外光谱、元素分析和X射线光电子能谱对其进行了全面表征。在1 - 4中，钯配合物和六钒酸盐阴离子通过静电相互作用组装。有趣的是，2和3中的V6O11(OMe)8核是一对异构体，可以通过控制结晶温度来分离。此外，据我们所知，3中的{V6}核代表一种新的八甲氧基六钒酸盐簇。值得注意的是，化合物1 - 4在以叔丁基过氧化氢为氧化剂氧化苄基烷烃的反应中表现出优异的多相催化性能。其中，1的催化活性（转化率和选择性分别高达99%）优于其他化合物，并且可以重复使用而不丧失其活性。
