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61.
Two octacyanometallate-based NiII–MIV [M?=?Mo(1), W(2)] bimetallic assemblies chelated with tetradentate macrocyclic ligands have been synthesized by slow diffusion and characterized structurally. In both complexes, M and Ni centers acting as linker and connector, respectively, are connected by M–CN–Ni–NC–M linkages to form a 3-D diamond-type topological network. Magnetic behaviors of both complexes show a very weak antiferromagnetic interaction between NiII ions mediated by the diamagnetic [M(CN)8]4? bridges.  相似文献   
62.
Two new discrete Btz-bridged pentanuclear metal complexes, [HDMF][NaHg4(Btz)6I4] (1) and [Zn5(Btz)6(L)3(Ac)]?·?0.5MeOH?·?0.5H2O (2) (Btz?=?deprotonated benzotriazole, L?=?p-aminobenzoate, HDMF?=?protonated DMF, and Ac?=?acetate), were synthesized using three-layered diffusion and natural evaporation methods, respectively. In 1, the pentanuclear anion [NaHg4(Btz)6I4]? is composed of a tetrahedral arrangement of four four-coordinate Hg(II) ions centered on the six-coordinate Na(I), and thereby forming a rare Btz-bridged hetero-metal complex. Compound 2 is a neutral pentanuclear homo-metal complex, consisting of a tetrahedral arrangement of four five-coordinate Zn(II) ions centered on the fifth six-coordinate Zn(II). The thermal stabilities and solid-state photoluminescence of the two complexes have been investigated.  相似文献   
63.
The crystal structure of the title complex was determined by single-crystal X-ray diffraction methods. The unit cell contains two independent molecules, A and B. B is a mononuclear Cu(II) complex with square-planar coordination geometry formed by two benzimidazole molecules and two hydroxylbenzoate anions. A is a dimer of B, formed by bridging hydroxybenzoate, and copper assumes square-pyramidal geometry. Aromatic π–π stacking is observed between parallel benzimidazole rings of neighboring A molecules. IR spectra of the compound are assigned in line with the crystal structure.  相似文献   
64.
Reaction of FeCl3 with one equivalent of acac (acac = pentane-2,4-dionate) and KTpMe2 (TpMe2 = hydrotris(3,5-dimethyl-pyrazol-1-yl)borate) yielded TpMe2Fe(acac)Cl (3), which upon reaction with methanolic solution of sodium azide resulted in the formation of a six coordinate compound TpMe2Fe(acac)N3 (4) with a single azide. When the reaction of FeCl3 and KTpMe2 was performed with two equivalents of sodium azide and one equivalent of 3,5-dimethylpyrazole (PzMe2H), a six coordinate cis azide compound [TpMe2Fe(PzMe2H)(N3)2] (5) was obtained. These compounds were characterized by spectroscopic methods and single crystal X-ray crystallography. Electrochemical studies of 5 show that it can be irreversibly reduced at relatively lower potential than 4. The photolysis of 5 was performed at 77 K at different wavelengths (480, 419, and 330 nm) showing that 5 was photoreduced to a high-spin Fe(II) species instead of photooxidized to Fe(V).  相似文献   
65.
The title complex has been synthesized and characterized by elemental and thermal analysis, IR and electronic spectroscopy, conductivity studies and X-ray crystallography. In the crystal, the complex has two-fold symmetry and the copper atom adopts square pyramidal coordination. Bond valences for Cu were computed. Cu–O(propionate) bonds are slightly stronger than the Cu–N bonds, and the Cu–O(water) bond is distinctly weaker. Molecules are linked by O–H···O hydrogen bonds to form infinite hydrogen-bonded chains along the y axis.  相似文献   
66.
Styrene–norbornene (S‐N) copolymerizations were carried out using β‐diketiminato nickel complexes CH{C(CF3)NAr}2NiBr (Ar = 2,6‐iPr2C6H3, 1 ; Ar = 2,6‐Me2C6H3, 2 ) in the presence of methylaluminoxane. The influence of the comonomer feed content and polymerization temperature on the conversion and composition of the copolymers with the catalytic system was investigated. An increase in the feed ratio of S/N led to an increase in the incorporated styrene content of the resulting copolymer. NMR characterization of the copolymers generated with the catalytic systems showed that the random S‐N copolymers are produced. Differential scanning calorimetric determination of the copolymers shows higher Tg values than polystyrene, and gel permeation chromatographic measurements have shown that the copolymers possess rather narrow molecular weight distributions, suggesting that the copolymerization take place at a single active site. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
67.
A path-integral Monte Carlo algorithm for the simulation of electrons solvated in polar liquids is briefly outlined, and results are presented for the electron solvated in liquid water.  相似文献   
68.
研究了二乙氨基环硫丙烷在三氟化硼-四氢呋喃络合物(RF3·THF)催化下的聚合反应.与使用BF3·Et2O作催化剂时聚合物沉淀析出的情况不同,在BF3·THF催化下,可得到均相粘性聚合物,而且部分四氢呋喃参与了共聚合反应.通过改变催化剂和溶剂的用量以及单体的加料方式制得了一系列组成和分子量不同的共聚物,用元素分析、核磁、红外、分子量测定等测试手段对聚合物进行了表征,还讨论了聚合反应的机理.  相似文献   
69.
将二茂铁甲酰丙酮与异菸肼缩合,生成金属有机多齿新配体,该配体(FCR)与闭式-十二氢十二硼酸稀土化合物反应,得到分子式为[Ln(FcR)2]2(B12H12)3·XH2O(Ln=La,Nd,Eu,Gd,Dy,Ho,Er,TmandLu)的9个配位化合物,经元素分析、红外光谱、紫外光谱对其组成、结构进行了表征,通过TG-DTA研究了它们的热行为.  相似文献   
70.
1,1’-联-2-萘酚硼烷的辛可宁和麻黄碱衍生物的合成单自兴,孙杰,段标,杨洗,赵德杰(武汉大学化学系,武汉,430072)关键词1,1’-联-2-萘酚,硼烷,辛可宁,麻黄碱,硼烷配合物,合成中国法分类号O627·31l,l’一联一2一条酚在大环化学...  相似文献   
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