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1.
The hydrothermal reaction of 1,2-dicyanobenzene with NaN3 in the presence of CuCl2, 2,2′-bipyridine and H2O affords a novel dinuclear copper(II)-ditetrazolate, [Cu(bpy)- (pdtz)]2 (Hpdtz = 5,5′-1,2-phenylene-ditetrazole, bpy = 2,2′-bipyridine). The pdtz ligand is generated in situ through Sharpless 2 3 cycloaddition reaction. Its crystal structure was deter- mined by single-crystal X-ray diffraction method. The crystal crystallizes in the monoclinic system, space group P21/n with a = 8.2096(16), b = 18.580(4), c = 11.838(2) , β = 103.12(3)o, V = 1758.5(6) 3, Z = 2, Mr = 863.83, Dc = 1.631 g/cm3, F(000) = 876 and μ = 1.272 mm-1. In this novel dinuclear structure, the pdtz ligand adopts a peculiar μ2-η1,η2 coordination mode.  相似文献   
2.
The first successful attempt to construct 3D supramolecular frameworks with high-nuclear 3d-4f heterometallic clusters as a node is reported. The self-assembly of Ln3+, Cu2+ and amino acid in solution leads to the formation of two polymers, 35-nuclear complex [Sm6Cu29] 1 with a primitive cubic net-like structure and 36-nuclear complex [Nd6Cu30] 2 with a face-centred cubic network type structure. Glycine and L-proline, respectively, were used as ligands. It should be noted that 2 has a chiral framework. X-ray structure analyses show that 1 crystallizes in the triclinic P1 space group (a=19.6451(8), b=20.4682(8), c=20.7046(8) A, alpha=89.453(1), beta=66.290(1), gamma=68.572(1) degrees, V=7003.0(5) A3 and Z=1) and 2 belongs to the cubic P2(1)3 space group (a=b=c=32.4341(3) A, V=34 119.7(5) A3 and Z=4). Both complexes utilize Ln6Cu24 octahedral clusters as nodes and trans-Cu(amino acid)2 groups as bridges. Electrical conductivity measurements reveal that both polymers behave as semiconductors.  相似文献   
3.
芳香环状低聚物组分分布与单体结构关系的研究   总被引:1,自引:0,他引:1  
根据Jacoson-Stockmayer(J-S)环化理论,应用基质辅助激光解吸离子化飞行时间质谱(MAIDL-TOFMS),对一系列芳香环状低聚物组分分布进行分析,研究了芳香环状低聚物的组分分布与单体结构的关系,结果表明,在芳香聚酯、聚膦酸酯及芳香聚醚环状低聚物系列中,Incn与Inn呈良好的线性关系,符合J-S理论分布,在环状聚酯及聚膦酸酯系列中,低聚物的组分分布受双酚单体的中心键角影响,单体的中心键角在100°~120°之间,其中心键角愈小,γ值愈大,而在聚醚系列中,在固定一种单体的前提下,环化物的组分分布受另一单体键角的影响与环状聚酯和聚膦酸酯相一致.  相似文献   
4.
A new mixed-valence cyanide-bridged complex, Br3Fe(μ-NC)RuBr(dppm)2(dppm = bis(diphenylphosphino)methane), was obtained through the reaction between trans-(dppm)2ClRuCN and FeBr3. Its crystal structure was characterized. Electronic absorption spectra indicate the existence of metal-to-metal charge transfer(MMCT) and this complex is Class Ⅱ mixed valence complexes according to the classification of Robin and Day. Magnetic analysis shows it is paramagnetic.  相似文献   
5.
以单分散SiO2为模板,通过简单的一步煅烧法制备具有分级孔结构的g-C3N4。与体相g-C3N4相比,分级孔结构的g-C3N4不仅可见光吸收性能和比表面积得到提高,而且更有利于光生电子-空穴的分离。此外,具有分级孔结构的g-C3N4具有明显增强的可见光驱动的光催化产氢活性,当SiO2和二氰二胺质量比为1∶1时,制备所得g-C3N4(C3N4-2)产氢速率几乎是体相g-C3N4的18倍。  相似文献   
6.
The hydrothermal reaction of 1,2-dicyanobenzene with NaN3 in the presence of Cd(NO3)2 affords a novel 2D cadmium tetrazolyl-benzoate,{Cd(tzbz)(H2O)}n (H2tzbz is 2-(5-tetrazolyl)-benzoate). The tzbz ligand is generated in situ through the 2+3 Sharpless cycloaddition reaction and hydrolyzation. Its crystal structure was determined by single-crystal X-ray diffraction method. The crystal crystallizes in the orthorhombic system,space group Pbca with a=9.6659(19),b=7.6366(15),c=25.964(5) ,V=1916.5(7) 3,Z=8,Mr=318.57,Dc= 2.208 g/cm3,F(000)=1232 and μ=2.276 mm-1. The Cd(Ⅱ) atom is coordinated by four tzbz ligands and one water molecule to form a severely distorted pentangle bipyramid. While each tzbz ligand connects to four Cd(Ⅱ) atoms in a μ4-η1,η2,η1,η1,η1 coordination mode to construct a 2D architecture of the title complex. Additionally,the title complex exhibits strong fluorescence at room temperature in the solid state.  相似文献   
7.
1 INTRODUCTION Amino acids (AA) are some of the most important biological ligands, and metal ions are known to par- ticipate in a variety of biological reactions, therefore, research on the coordination behavior of metal-ami- no acid complexes is one of the most essential ele- ments of chemical biology[1, 2]. For over three deca- des their structures have been of considerable inte- rest and importance in coordination chemistry[2, 3]. Studies of these relatively simple complexes may en- ha…  相似文献   
8.
Treatment of resorcin[4]arene tetracarboxylic acid 1 with triethylamine in the presence of Co(CH3COO)2·4H2O and 4,4'-bipyridine gave a co-crystallization 14-·4Et3NH+(C32H20O164-·4Et3NH+,Mr=1069.27) from ethanol and water.The compound was structurally determined by single-crystal X-ray diffraction.The crystal belongs to monoclinic,space group P21/n,with a=8.1763(18),b=12.913(3),c=28.724(7) ,β=97.574(4)o,V=3006.3(12) 3,Z=2,Dc=1.181 g/cm3,F(000)=1152,Rint=0.0275,T=293(2) K,μ=0.086 mm-1,the final R=0.0634 and wR=0.1752 for 5082 observed reflections with Ⅰ 2σ(Ⅰ).The co-crystallization is very stable at room temperature.Possibly,a network of N-H···O(=C) plays an important role in the structure.Meanwhile,the compound emits a weak cyan luminescence with peak maximum band at 458 nm.  相似文献   
9.
A new tri-nuclear mixed metal thiolate complex [Ag(PPh3)2]2[Ni(edtO2)2] 1 has been synthesized and structurally characterized by single-crystal diffraction.The molecule has a crystallographic inversion centre occupied in the central Ni(II) atom and the two silver(I) atoms are related by the inversion centre.The unique structural feature is that one of thiolates of each edt ligand has been oxidized to sulfinate from the precursor [Ni(edt)2]2-to the neutral linear trinuclear complex.The crystal structure belongs to the monoclinic system,space group P21/n with a = 13.581(11),b = 12.239(9),c = 22.316(17) ,β = 103.08(2)o,V = 3613(5) 3,Z = 2,Mr = 1571.87,Dc = 1.445 g/cm3,μ = 1.046 mm-1,F(000) = 1604,T = 293(2) K,the final R = 0.0652 and wR = 0.1499 for 6776 observed reflections with I > 2σ(I).  相似文献   
10.
Wu HP  Huang CC  Cheng TL  Tseng WL 《Talanta》2008,76(2):347-352
A sensor for detecting cysteine (Cys) in a solution of fluorosurfactant (FSN)-capped gold nanoparticles (AuNPs) has been developed. Under acidic conditions, FSN-capped AuNPs are aggregated in the presence of homocysteine (HCys) and Cys but not in the presence of cysteinylglycine, glutathione, and gamma-glutamycysteine. When adding NaOH to a solution of HCys, the five-membered ring transition state is formed through intramolecular hydrogen abstraction. By contrast, it is difficult for Cys to form a four-membered ring transition state after Cys has been pretreated with NaOH. As a result, the HCys-induced aggregation of the FSN-capped AuNPs is suppressed because the five-membered ring transition state exhibits relatively larger steric hindrance and has stronger interaction with the FSN molecules. Thus, we can discriminate between Cys and HCys on the basis of different aggregation kinetics. Under the optimum condition, the selectivity of the probe for Cys in aqueous solutions is remarkably high over the other aminthiols. Note that HCys and Cys have very similar structure and pK(a) value. We have validated the applicability of our method through the analyses of Cys in urine samples. It is believed that this approach has great potential for the detection of Cys in biological samples.  相似文献   
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