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1.
A simple and efficient catalytic system for Na2PdCl4 catalyzing the Suzuki‐Miyaura reaction of dibromobenzene and arylboronic acid has been developed by using 2N2O‐salen as a ligand in H2O/EtOH (V:V=4:1) at 100°C. Using this method, the reactions of substrates containing sterically demanding ortho substituents (e.g. dibromobenzene and/or arylboronic acids) proceeded efficiently, with the corresponding terphenyl derivatives being produced in moderate to excellent yields. Furthermore, this method offers interesting features for the multi‐gram scale synthesis of terphenyl compound.  相似文献   

2.
A concise route to access 5H‐imidazo[2,1‐a]isoindole heterofused compounds by copper(I)‐catalyzed intramolecular coupling of non‐activated aryl bromides with azoles is reported. With CuI as catalyst, 1,10‐phenanthroline as ligand, and K3PO4 as base, the reactions of 1‐(2‐bromobenzyl)‐1H‐imidazoles in DMF/o‐xylene (1:1, V:V) at 145°C afford the corresponding substituted 5H‐imidazo[2,1‐a]isoindoles in high yields via intramolecular C‐arylation.  相似文献   

3.
A simple and rapid RP‐HPLC‐DAD method was developed and validated for simultaneous determination of the dopamine antagonists haloperidol, its diazepane analog, and the dopamine agonist bromocriptine in rat plasma, to perform pharmacokinetic drug‐interaction studies. Samples were prepared for analysis by acetonitrile (22.0 μg/mL) plasma protein precipitation with droperidol as an internal standard, followed by a double‐step liquid‐liquid extraction with hexane : chloroform (70:30) prior to C‐18 separation. Isocratic elution was achieved using a 0.1% (v/v) trifluoroacetic acid in deionized water, methanol and acetonitrile (45/27.5/27.5, v/v/v). Triple‐wavelength diode‐array detection at the λmax of 245 nm for haloperidol, 254 nm for the diazepane analog and droperidol, and 240 nm for bromocriptine was carried out. The LLOQ of DAL, HAL, and BCT were 45.0, 56.1, and 150 ng/mL, respectively. In rats, the estimated pharmacokinetic parameters (i.e., t1/2, CL, and Vss) of HAL when administered with DAL and BCT were t1/2 = 16.4 min, Vss = 0.541 L/kg for HAL, t1/2 = 28.0 min, Vss = 2.00 L/kg for DAL, and t1/2 = 24.0 min, Vss = 0.106 L/kg for BCT. The PK parameters for HAL differed significantly from those previously reported, which may be an indication of a drug‐drug interaction. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

4.
The combination of N‐heterocyclic and multicarboxylate ligands is a good choice for the construction of metal–organic frameworks. In the title coordination polymer, poly[bis{μ2‐1‐[(1H‐benzimidazol‐2‐yl)methyl]‐1H‐tetrazole‐κ2N3:N4}(μ4‐butanedioato‐κ4O1:O1′:O4:O4′)(μ2‐butanedioato‐κ2O1:O4)dicadmium], [Cd(C4H4O4)(C9H8N6)]n, each CdII ion exhibits an irregular octahedral CdO4N2 coordination geometry and is coordinated by four O atoms from three carboxylate groups of three succinate (butanedioate) ligands and two N atoms from two 1‐[(1H‐benzimidazol‐2‐yl)methyl]‐1H‐tetrazole (bimt) ligands. CdII ions are connected by two kinds of crystallographically independent succinate ligands to generate a two‐dimensional layered structure with bimt ligands located on each side of the layer. Adjacent layers are further connected by hydrogen bonding, leading to a three‐dimensional supramolecular architecture in the solid state. Thermogravimetric analysis of the title polymer shows that it is stable up to 529 K and then loses weight from 529 to 918 K, corresponding to the decomposition of the bimt ligands and succinate groups. The polymer exhibits a strong fluorescence emission in the solid state at room temperature.  相似文献   

5.
Five mixed‐metal mixed‐valence Mo/V polyoxoanions, templated by the pyramidal SeO32? heteroanion have been isolated: K10[MoVI12VV10O58(SeO3)8]?18 H2O ( 1 ), K7[MoVI11VV5VIV2O52(SeO3)]?31 H2O ( 2 ), (NH4)7K3[MoVI11VV5VIV2O52(SeO3)(MoV6VV‐ O22)]?40 H2O ( 3 ), (NH4)19K3[MoVI20VV12VIV4O99(SeO3)10]?36 H2O ( 4 ) and [Na3(H2O)5{Mo18?xVxO52(SeO3)} {Mo9?yVyO24(SeO3)4}] ( 5 ). All five compounds were characterised by single‐crystal X‐ray structure analysis, TGA, UV/Vis and FT‐IR spectroscopy, redox titrations, and elemental and flame atomic absorption spectroscopy (FAAS) analysis. X‐ray studies revealed two novel coordination modes for the selenite anion in compounds 1 and 4 showing η,μ and μ,μ coordination motifs. Compounds 1 and 2 were characterised in solution by using high‐resolution ESI‐MS. The ESI‐MS spectra of these compounds revealed characteristic patterns showing distribution envelopes corresponding to 2? and 3? anionic charge states. Also, the isolation of these compounds shows that it may be possible to direct the self‐assembly process of the mixed‐metal systems by controlling the interplay between the cation “shrink‐wrapping” effect, the non‐conventional geometry of the selenite anion and fine adjustment of the experimental variables. Also a detailed IR spectroscopic analysis unveiled a simple way to identify the type of coordination mode of the selenite anions present in POM‐based architectures.  相似文献   

6.
The new monomer N′‐(β‐methacryloyloxyethyl)‐2‐pyrimidyl‐(p‐benzyloxy‐ carbonyl)aminobenzenesulfonamide (MPBAS) (M1) is synthesized using sulfadiazine as parent compound. It could be homopolymerized and copolymerized with N‐phenyl maleimide (NPMI) (M2) by radical mechanism using AIBN as initiator at 60 °C in dimethylformamide. The new monomer MPBAS and polymers were identified by IR, element analysis and 1H NMR in detail. The monomer reactivity ratios in copolymerization were determined by YBR method, and r1 (MPBAS) = 2.39 ± 0.05, r2 (NPMI) = 0.33 ± 0.02. In the presence of ammonium formate, benzyloxycarbonyl groups could be broken fluently from MPBAS segments of copolymer by catalytic transfer hydrogenation, and the copolymer with sulfadiazine side groups are recovered. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2548–2554, 2000  相似文献   

7.
For the purpose of developing poly(3‐hexylthiophene) (P3HT) based copolymers with deep‐lying highest occupied molecular orbital (HOMO) levels for polymer solar cells with high open‐circuit voltage (Voc), we report a combined approach of random incorporation of 3‐cyanothiophene (CNT) and 3‐(2‐ethylhexyl)thiophene (EHT) units into the P3HT backbone. This strategy is designed to overcome CNT content limitations in recently reported P3HT‐CNT copolymers, where incorporation of more than 15% of CNT into the polymer backbone leads to impaired polymer solubility and raises the HOMO level. This new approach allows incorporation of a larger CNT content, reaching even lower‐lying HOMO levels. Importantly, a very low HOMO level of ?5.78 eV was obtained, representing one of the lowest HOMO values for exclusively thiophene‐based polymers. Lower HOMO levels result in higher Voc and higher power conversion efficiencies (PCE) compared to the previously reported P3HT‐CNT copolymers containing only 3‐hexylthiophene and CNT units. As a result, solar cells based on P3HT‐CNT‐EHT(15:15) , which contains 70% of P3HT, 15% of CNT and 15% of EHT, yield a Voc of 0.83 V in blends with PC61BM while preserving high fill factor (FF) and high short‐circuit current density (Jsc), resulting in 3.6% PCE. Additionally, we explored the effect of polymer number‐average molecular weight (Mn) on the optoelectronic properties and solar cell performance for the example of P3HT‐CNT‐EHT(15:15). The organic photovoltaic (OPV) performance improves with polymer Mn increasing from 3.4 to 6.7 to 9.6 kDa and then it declines as Mn further increases to 9.9 and to 16.2 kDa. The molecular weight study highlights the importance of not only the solar cell optimization, but also the significance of individual polymer properties optimization, in order to fully explore the potential of any given polymer in OPVs. The broader ramification of this study lies in potential application of these high band gap copolymers with low‐lying HOMO level in the development of ternary blend photovoltaics as well as tandem OPV. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1526–1536  相似文献   

8.
Amantadine (AMA) is an anti‐viral drug used in apiculture to protect honeybee against the sacbrood virus (Morator aetatulae). This study described a reliable high‐performance liquid chromatographic (HPLC) method for analyzing AMA in honey using a solid‐phase extraction (SPE) cartridge (Plexa PCX) for purification, 4‐fluoro‐7‐nitro‐2,1,3‐benzoxadiazole (NBD‐F) as a pre‐column derivatization agent, and fluorometric detection (λex=470 nm, λem=530 nm). The chromatographic separation was performed on an XDB C18 column (150×4.6 mm i.d.) using 0.1% trifluoroacetic acid/acetonitrile (35:65,V/V) as the mobile phase at a flow rate of 1.0 mL·min−1 with a run time of 20 min. Under these optimal conditions, a linear relationship was observed in the range of 0.025–1.0 µg· mL−1 with a good correlation coefficient (0.998) and low limit of detection (0.0080 µg·g−1), the recoveries were all above 90%, and the intra‐day and inter‐day precision (RSD) ranged from 3.4%–5.1%.  相似文献   

9.
The new spectrophotometric assay method for the quantification of peroxidase activity uses 4‐amino‐5‐hydroxynaphthalene‐2,7‐disulfonicacid monosodium salt (AHNDSA) as chromogenic co‐substrate. The method is based on hydroxylation of AHNDSA in presence of H2O2/peroxidase forming quinone, having λmax = 460 nm in the acetate buffer (pH = 4.0) at 30 °C. The linearity of H2O2 by kinetic method was 10–332 µM and for peroxidase by kinetic and fixed time methods were 1.18–18.92 and 1.18–9.46 nM, respectively. Catalytic efficiency and catalytic power for peroxidase assay were 7.965 × 104 M?1min?1 and 3.76 × 10?4 min?1, respectively. From the plot of d(1/Ao) vs d(1/Vo) and d(1/Ho) vs d(1/Vo), the apparent Michaelis‐Menten constants for H2O2 and AHNDSA were K = 68 and K = 275 µM, respectively. The method was tested with some plant extracts and also compared with guaiacol/peroxidase system. Except Boerhavia diffusa, all other tested plant samples showed highest peroxidase activity. The proposed method is a rapid and convenient method to determine peroxidase activity by spectrophotometer. This method for the first time reports peroxidase activity in Lantana camara and Oplismenus compositus plants. Kinetic results showed that AHNDSA/peroxidase system can be better hydrogen donor for peroxidase assay than guaiacol system.  相似文献   

10.
Single crystals of {[Cu(TO)2(H2O)2](NO3)2}n (TO: 1, 2, 4‐triazol‐5‐one) were grown by slow evaporation from aqueous solution. It crystallizes in the orthorhombic space group Pbca, with a = 7.082(1), b = 10.285(1), c = 17.911(3)Å, V = 1304.6(3)Å3, Z = 4. The CuII distorted octahedra are bridged by bidentate TO ligands into infinite 2‐D interlaced rhombic grid‐like network planes, {[Cu(TO)2(H2O)2]2+}n. Hydrogen bonds, electrostatic interactions, and weak van der Waals' forces assemble these planes and the NO3 anions to a layered structure. The title compound decomposes at 153.4 °C to the final products, Cu(CN)2 and CuO.  相似文献   

11.
The electronic states of halide ions are modeled by a one‐dimensional Hamiltonian with a potential V(x)=−V0e. The two parameters V0 and σ are fixed by requiring V(x) to reproduce the experimentally observed ground‐state ionization potentials of the halide ions concerned. The potentials so generated are shown to support only one bound state in each case. The time‐dependent Fourier grid Hamiltonian method is used to follow the ionization dynamics in monochromatic light of fairly high intensities. The total Hamiltonian, in the most general case, reads H(t)=P/2mV0e−ϵ0s(t)ex sin(ωt). For pulsed fields [s(t)=sin2t/tp)], the computed ionization rate constants are seen to increase with increase in the peak intensity (ϵ0) of the electric field of light. The possibility of additional transient bound states being generated at the high intensities of light and its possible consequences on the observed ionization rates are explored. The environmental effects on the dynamics are sought to be modeled by allowing the well depth (V0) to fluctuate randomly [V0(t)=V0VR(t); R(t) randomly fluctuates between +1 and −1 with time, ΔV is fixed]. The ionization rate constants (kϵ) are shown to be significantly affected by fluctuations in V0 and pass through a well‐defined minimum in each case for a certain specified frequency of fluctuation. An alternative model potential V(x)=−V0e−σx is also shown to yield similar results. ©1999 John Wiley & Sons, Inc. Int J Quant Chem 73: 469–478, 1999  相似文献   

12.
The crystalline structure of mangiferin (=2‐β‐D ‐glucopyranosyl‐1,3,6,7‐tetrahydroxy‐9H‐xanthen‐9‐one; 1 ), a biologically active xanthenone C‐glycoside, isolated from the stem bark of Mangifera indica (Anacardiaceae), was unambiguously determined by single‐crystal X‐ray diffraction (XRD). The crystal structure is summarized as follows: triclinic, P1, a=7.6575(5), b=11.2094(8), c=11.8749(8) Å, α=79.967(5), β=87.988(4), γ=72.164(4)°, V=955.3(1) Å3, and Z=2. The structure also shows two molecules in the asymmetric unit cell and five crystallization H2O molecules. The packing is stabilized by several intermolecular H‐bonds involving either the two symmetry‐independent mangiferin molecules 1a and 1b , or the H2O ones.  相似文献   

13.
A new three‐dimensional open‐framework cobalt‐zinc phosphite [Co(H2O)4Zn(HPO3)2]·H2O ( 1 ), has been prepared under hydrothermal conditions and characterized by single‐crystal X‐ray diffraction, XRD, IR and SQUID magnetometer. The compound crystallizes in the triclinic space group with a = 7.552(5), b = 7.671(5), c = 9.443(5) Å, α = 88.538(5)°, β = 89.109(5)°, γ = 87.056(5)°, V = 546.1(6) Å3, Z = 2. The structure of 1 consists of corner‐shared (cs) four‐membered‐ring chains formed by alternating ZnO4 tetrahedra and HPO3 pseudopyramids, which are further linked through CoO2(H2O)4 octahedra giving rise to a three‐dimensional (3‐D) neutral open‐framework with intersecting 12‐ and 16‐MR channels. The synthesis of system required the presence of L‐histidine which is not incorporated into the structure of the product. It is noteworthy that compound 1 represents the only known example of purely inorganic open‐framework cobalt‐zinc phosphite.  相似文献   

14.
In tandem : Employing a molecular dyad and a cobalt‐based electrolyte gives a threefold‐increase in open‐circuit voltage (VOC) for a p‐type NiO device (VOC=0.35 V), and a fourfold better energy conversion efficiency. Incorporating these improvements in a TiO2/NiO tandem dye‐sensitized solar cell (TDSC), results in a TDSC with a VOC=0.91 V (see figure; CB=conductance band, VB= valence band).

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15.
The polyoxometalate compound [CuPTCP(H2O)2.5]2[SiW12O40] · 10.5H2O ( 1 ) was synthesized under hydrothermal conditions using 2‐phenyl‐1H‐1,3,7,8‐tetraazacyclopenta[l]phenanthrene (PTCP) and Keggin‐type silicotungstic acid (H4SiW12O4) as neutral ligands. Compound 1 was characterized by single‐crystal X‐ray diffraction, elemental analysis, as well as IR and UV/Vis spectroscopy. It crystallizes in the orthorhombic space group Cmcm with a = 15.490(8) nm, b = 25.263(8) nm, c = 20.988(8) nm, α = 90°, β = 90°, γ = 90°, V = 8213(6) nm3, Z = 2. Compared with the ligand PTCP, the fluorescent spectra of compound 1 are different. Furthermore, the Rhodamine B (RhB) photodegration process by compound 1 as catalyst was studied. It could be shown that the DR% of compound 1 is more than twice that of pure silicotungstic acid.  相似文献   

16.
The crystal structures of an unexpected carbon dioxide inserted carbamidiphenylthiophosphinic anhydride and l‐[(4‐nitrophenyl) sulfonyl]‐trans‐2, 5‐pyrrolidinedicarboxylic acid methyl ester were determined by X‐ray analysis. They crystallized in the space group P21(#4) with a =0.9550(2), b = 0.9401(4), c= 1.2880(2) nm, β= 107.74°, V= 1.1013 (5) nm3, Dcaled= 1.349 g/cm3, Z = 2 and P212121(# 19) with a = 1.4666(2), b = 0.7195(2), c = 1.6339(2) nm, V = 1.7240(7) nm3, Dcaled = 1.434 g/cm3, Z = 4, respectively. Through the investigation of these two crystal structures, the mechanistic insights into this unexpected carbon dioxide insertion in the reaction of trans‐2,5‐disubstituted pyrrolidine with diphenylthiophosphoryl chloride in the presence of potassium carbonate were disclosed.  相似文献   

17.
陈文斌  李牛  项寿鹤 《中国化学》2005,23(3):255-260
本文报道了一种新型三维亚磷酸锌[HO(CH2)2NH3]2•[Zn3(HPO3)4]的合成和晶体结构。在它的结构中,ZnO4和HPO3严格按照顶点连接的方式交替相连。骨架结构存在两个沿着不同方向无限延伸的由ZnO4和HPO3组成的四元环链,在[0 1 0]、[0 4 15]和[0 -4 15]三个方向形成了三个交叉8元环孔道,有机胺阳离子起着平衡电荷和稳定骨架的结构。它的晶体数据为:[HO(CH2)2NH3]2•[Zn3(HPO3)4],M=640.21, 正交晶系, Fdd2空间群, a=2.8528, b=0.8426, c=1.6159nm, Z=8, V=3.884nm3, R1=0.0219, wR2=0.0544。  相似文献   

18.
本文合成了并培养出了七-O-乙酰基—β—乳糖异硫氰酸酯的单晶,用X射线衍射分析了其晶体结构。结果表明,晶体为正交晶系,P212121空间群,a=1.23282(7),b=1.80012(10),c=1.85230(10) nm,α=β=γ=90°,V=4.1107(4) nm3,Z=4。电化学实验观测到单链DNA和双链DNA对该化合物的峰电流均有明显降低作用,表明化合物与DNA发生了静电作用。  相似文献   

19.
The synthesis, characterization, and photophysical and photovoltaic properties of two anthracene‐containing wide‐band‐gap donor and acceptor (D–A) alternating conjugated polymers ( P1 and P2 ) are described. These two polymers absorb in the range of 300–600 nm with a band gap of about 2.12 eV. Polymer solar cells with P1 :PC71BM as the active layer demonstrate a power conversion efficiency (PCE) of 2.23% with a high Voc of 0.96 V, a Jsc of 4.4 mA cm−2, and a comparable fill factor (FF) of 0.53 under simulated solar illumination of AM 1.5 G (100 mW cm−2). In addition, P2 :PC71BM blend‐based solar cells exhibit a PCE of 1.42% with a comparable Voc of 0.89 V, a Jsc of 3.0 mA cm−2, and an FF of 0.53.

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20.
Three mononuclear vanadium complexes containing aromatic 1, 2‐diols (catechol and naphthalene‐2, 3‐diol) ligands,[VIVO(cat)2][1, 3‐HPDA]2 · CH3OH ( 1 ), [VIVO(N‐2, 3‐D)2][1, 3‐H2PDA] ( 2 ), and [VVO2(N‐2, 3‐D)(1, 3‐HPDA)] · 1, 3‐PDA ( 3 ) (cat = catechol, N‐2, 3‐D = naphthalene‐2, 3‐diol, 1, 3‐PDA = 1, 3‐propanediamine) were synthesized and characterized by X‐ray diffraction, IR and UV/Vis spectroscopy, and cyclovoltammetry. X‐ray analysis reveals that the spatial frameworks of complexes 1 – 3 are all constructed by hydrogen bonds donated by [1, 3‐HnPDA]n+ (n = 1, 2) cation, forming distinct chain structures. Complexes 1 and 2 are both in the non‐chiral form of VO(L)2, but 2 crystallizes in the chiral space group (P6522), due to the symmetry element of spiral axis, whereas complex 3 contains both enantiomers of chiral VO2(L1)(L2) units, but crystallizes in the non‐chiral space group (P$\bar{1}$ ). The electrochemical behavior of the three complexes is studied in comparison with that of the free ligands. Complex 1 shows a pair of potentials assigned to the redox behavior of vanadium, while complexes 2 and 3 exhibit no such redox potentials. Pharmaceutical screening of complexes 1 – 3 were carried out against three representative cancer cell lines: A‐549 (lung cancer), Bel‐7402 (liver cancer) and HCT (colonic cancer) by MTT [3‐(4, 5‐dimethylthiazoyl‐2‐yl)‐2, 5‐diphenyltetrazolium bromide] assay. The results show that the vanadium‐catechol complex 1 exhibits more obvious anti‐proliferating effects against the three cell‐lines, whereas the two vanadium‐N‐2, 3‐D complexes 2 and 3 basically display no such effects.  相似文献   

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