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131.
A novel heterobimetaUic coordination polymer, {(NH4)2[Cd(H20)Fe(CN)6]}n 1, has been synthesized by using the slow diffusion method and structurally characterized by elemental analysis, 1R spectroscopy and single-crystal X-ray diffraction. The crystal crystallizes in the monoclinic system, space group P21/n, a = 7.4202(16), b = 14.939(3), c = 10.868(2) A and ,8 = 91.660(3)°. For 1, five CN groups of Fe(CN)6]4- are involved in bridging. The polymer displays a 3D open microporous framework with 5-connected uninodal (46.64) topology.  相似文献   
132.
The stereospecific 1,2-migration of boronate complexes is one of the most representative reactions in boron chemistry. This process has been used extensively to develop powerful methods for asymmetric synthesis, with applications spanning from pharmaceuticals to natural products. Typically, 1,2-migration of boronate complexes is driven by displacement of an α-leaving group, oxidation of an α-boryl radical, or electrophilic activation of an alkenyl boronate complex. The aim of this article is to summarize the recent advances in the rapidly expanding field of electrophile-induced stereospecific 1,2-migration of groups from boron to sp2 and sp3 carbon centers. It will be shown that three different conceptual approaches can be utilized to enable the 1,2-migration of boronate complexes: stereospecific Zweifel-type reactions, catalytic conjunctive coupling reactions, and transition metal-free sp2–sp3 couplings. A discussion of the reaction scope, mechanistic insights, and synthetic applications of the work described is also presented.  相似文献   
133.
《中国化学快报》2020,31(11):2960-2964
Three fluorescent BINOL-Si complexes (FS1, FS2 and FS3) were rationally designed and synthesized to detect diethyl chlorophosphate (DCP), a mimic of lethal nerve agents. These three fluorescent probes showed green, yellow and orange fluorescence, respectively. Moreover, the series of fluorescent probes has the characteristics of fast response time (≤ 4 s), low detection limit (0.0097 μmol/L), high sensitivity and naked eye detection. More important, a fiber optic sensor capable of detecting DCP vapor in real time was also prepared for the first time, the lowest detection limits (down to 4.4 ppb) were all lower than that of the IDLH (immediately dangerous to life or health) concentration of Sarin (7.0 ppb).  相似文献   
134.
An electrochemical sensor based on the conducting polymer composite with a palladium complex (Pd(C2H4N2S2)2) was developed for the detection of serotonin and dopamine simultaneously in the breast cancer cell and human plasma samples. The proposed sensor was fabricated using the Pd(C2H4N2S2)2 complex‐anchored poly2,2 : 5,2‐terthiophene‐3‐(p‐benzoic acid) (pTBA) layer on the AuNPs decorated reduced graphene oxide (AuNPs@rGO) substrate, which revealed the enhanced anodic current of the target species. The sensor probe was characterized by electrochemical and surface analysis methods. The experimental parameters affecting the sensor performance were optimized, in terms of AuNPs@rGO concentration, the number of electropolymerization cycle for pTBA, immobilization time of Pd(C2H4N2S2)2, and pH. The dynamic ranges for serotonin and dopamine were obtained from 0.02 to 200 μM, and from 0.1 to 200 μM with the detection limit of 2.5, and 24.0 nM, respectively. The reliability of proposed sensor was evaluated using cancer cell lines for the clinical applications.  相似文献   
135.
Silica-supported polystannazane–copper complex has been prepared and used as a catalyst for the oxidation of methanol. The results showed that the catalyst could catalyze the oxidation of methanol to formaldehyde at a high yield and selectivity at 30°C and under 1 atm mild conditions. The N/Cu mole ratio in the complex, temperature and the amount of NaOH additive had much influence on the catalytic activity. The complex was stable during the reaction and could be used repeatedly.  相似文献   
136.
A new class of paramagnetic macromolecular magnetic resonance imaging contrast agents has been developed. Eight new polyamide ligands were synthesized by copolymerization of ethylenediaminetetraacetic acid dianhydride or diethylenetriaminepentaacetic acid dianhydride and diamine monomers. Their gadolinium(III), manganese(II) and iron(III) complexes were also synthesized. All polyamide ligands and metal complexes were characterized by 1H nuclear magnetic resonance, infrared spectra and elemental analyses. Relaxivity studies showed that the polyamide paramagnetic metal complexes had obviously higher relaxation effectiveness as compared to corresponding simple monomeric paramagnetic metal complexes.  相似文献   
137.
The epoxidation of styrene to styrene oxide at higher than 96% yield has been achieved by the catalysis by poly-(vinylbenzyl)acetylacetonate complexes of cobalt(II) or manganese(II) in the presence of isobutyraldehyde under an atmospheric pressure of molecular oxygen at room temperature. The kind of aldehyde and aldehyde/styrene molar ratio greatly influenced the reaction. The catalyst could be recycled, but after recycling for five times, the yield of styrene oxide decreased from 96.0% to 84.6%.  相似文献   
138.
Two new ternary complexes [Zn(3-aba)2(phen)](2.58H2O 1 and {[Cd(3-aba)- (phen)2]·(NO3)·(1.5H2O)}n 2 (3-aba = 3-aminobenzoic acid anion, phen = 1,10-phenanthroline) were synthesized and characterized by elemental analysis, IR, UV spectrum and X-ray diffraction. Complex 1 crystallizes in the rhombohedral system, space group R with a = 3.5733(3), b = 3.5733(3), c = 1.1231(2) nm, V = 12.419(3) nm3, C26H25.17N4O6.58Zn, Mr = 564.37, Z = 18, F(000) = 5253, μ = 0.937 mm-1, Dc = 1.358 g/cm3, R = 0.0668 and wR = 0.1690 for 2424 observed reflections (I > 2σ(I)). Complex 2 belongs to the tetragonal system, space group P4/ncc with a = 2.88451(10), b = 2.88451(10), c = 1.55571(11) nm, V = 12.9441(11) nm3, C31H25CdN6O6.50, Mr = 697.97, Z = 16, F(000) = 5648, μ = 0.727 mm-1, Dc = 1.433 g/cm3, R = 0.0607 and wR = 0.1742 for 3468 observed reflections (I > 2σ(I)). Complex 1 displays a mononuclear structure. The carboxylate group of 3-aminobenzoic acid anion coordinates to Zn(Ⅱ) in a chelating bidentate mode, and the nitrogen atom of the ligand does not involve in coordination. Complex 2 exhibits a one-dimensional chain structure with 3-aminobenzoic acid anion coordinating to Cd(Ⅱ) in a μ2-bridging mode through its nitrogen atom and one of its oxygen atoms.  相似文献   
139.
三功能合一的含铽高聚物的光谱性质研究   总被引:1,自引:1,他引:0  
制备了一种新型的可平衡电荷(空穴与电子)传输的含铽高聚物。用红外光谱、飞行时间二次离子质谱、紫外光谱研究了其光谱性质,确认这种高聚物含有咔唑、铽络合物、噁二唑单元。用荧光光谱研究了不同状态下高聚物的荧光性质,来自共轭基团的荧光出现“荧光猝灭”。在紫外光照射下,高聚物可发出具有铽离子特征发射的纯绿光。  相似文献   
140.
分别采用514 nm绿光、488 nm蓝光和390 nm紫外光作为敏化光,633 nm红光作为记录光,详细研究了敏化光波长对氧化(Fe,Ni):LiNbO3晶体全息记录性能的影响.结果表明:随着敏化光波长的逐渐减小,氧化(Fe,Ni):LiNbO3晶体的非挥发全息记录性能逐渐优化,390 nm紫外光是这三种敏化光中最优的敏化光.考虑敏化光的吸收,为了在双中心全息记录中获得最优的性能,应当选择合适波长的敏化光:一方面短波长敏化光能有效地敏化深中心;另一方面短波长敏化光的吸收太强(如对光折变效应无用的基质吸收),不能沿厚度方向有效地敏化晶体,所以实际上需折衷考虑,并从理论上给予了解释.  相似文献   
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