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1.
用1300-Ⅱ型吸附树脂吸附噻唑偶氮类试剂制取浸渍树脂。研究了树脂对试剂和对金的吸附率及其与溶液pH值的关系,求得浸渍树脂吸附金的平衡速率和吸附容量,并在条件试验基础上拟订了柱操作分离富集微量金的方法,获得了满意的结果。  相似文献   

2.
The triphenyltin(IV) complexes of 4-[((E)-1-{2-hydroxy-5-[(E)-2-(2-carboxyphenyl)-1-diazenyl]phenyl}methylidene)amino]aryls (aryls = 4-CH3, 4-Br, 4-Cl, 4-OCH3) have been synthesized and characterized by 1H-, 13C-, 119Sn-NMR, ESI mass spectrometry, IR and 119mSn Mössbauer spectroscopic techniques in combination with elemental analysis. The crystal structures of a representative carboxylate ligand (aryl = 4-CH3) and three Sn complexes, viz., polymeric (Ph3Sn[O2CC6H4{NN(C6H3-4-OH(C(H)NC6H4X-4))}-o])n (X = Me (1) and Br (2)) and dimeric (Ph3Sn[O2CC6H4{NN(C6H3-4-OH(C(H)NC6H4X-4))}-o])2 (X = OMe (4)) complexes are reported. The coordination environment in each complex is trigonal bipyramidal trans-Ph3SnO2. A single zwitterionic carboxylate ligand bridges adjacent Sn atoms via the carboxylate and phenoxide O atoms.  相似文献   

3.
3-[(E)-Arylmethylidene]-3,9-dihydropyrrolo[2,1-b]quinazolin-1(2H)-ones were prepared by reaction of quinazolyl-2-propionic acid hydrochloride with aromatic aldehydes in acetic anhydride in the presence of Et3N. 3-[(E)-Arylmethylidene]-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazolin-1-ols were formed by reduction of the 3-arylidene derivatives with sodium borohydride in methanol, readily lost water when heated with acids, and were converted into 3-[(E)-arylmethylidene]-3,9-dihydropyrrolo[2,1-b]quinazolines. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 463–467, September–October, 2006.  相似文献   

4.
在氧化铜和溴化铜存在的条件下, 4-[1,2-(2-吡啶基)亚甲硫基]-苯甲酸(L′)经原位消去反应, 形成了一个新的有机配体4-[1,2,2-(2-吡啶基)-(2-吡啶亚甲基)亚甲硫基]-苯甲酸(L), 并与铜形成配位聚合物[Cu2(L)Br2]n(1){L=4-[1,2,2-(2-吡啶基)-(2-吡啶亚甲基)亚甲硫基]-苯甲酸}, 通过红外光谱、元素分析和X射线单晶衍射等手段对其结构进行了表征.  相似文献   

5.
The conformational composition of gaseous MTMNB and the molecular structures of the rotational forms have been studied by electron diffraction at 130C aided by results from ab initio and density functional theory calculations. The conformational potential energy surface has been investigated by using the B3LYP/6-31G(d,p) method. As a result, six minimum-energy conformers have been identified. Geometries of all conformers were optimized using MP2/6-31G(d,p), B3LYP/6-31G(d,p), and B3LYP/cc-pVTZ methods. These calculations resulted in accurate geometries, relative energies, and harmonic vibrational frequencies for all conformers. The B3LYP/cc-pVTZ energies were then used to calculate the Boltzmann distribution of conformers. The best fit of the electron diffraction data to calculated values was obtained for the six conformer model, in agreement with the theoretical predictions. Average parameter values (ra in angstroms, angle α in degrees, and estimated total errors given in parentheses) weighted for the mixture of six conformers are r(C–C) = 1.507(5), r(C–C)ring, av = 1.397(3), r(C–S)av = 1.814(4), r(C–N) = 1.495(4), r(N–O)av = 1.223(3), ∠(C–C–C)ring = 116.0–122.5, ∠ C6–C4–C7 = 118.2(4), ∠ C–C–S = 113.6(6), ∠ C–S–C = 98.5(12), ∠ N–C–C4 = 121.9(3), ∠(O–N–C)av = 116.8(3), ∠ O–N–O = 127.0(4). Torsional angles could not be refined. Theoretical B3LYP/cc-pVTZ torsional angles for the rotation about C–N bond, φCN, were found to be 30.5–36.5 for different conformers. As to internal rotation about C–C and C–S bonds, values of φCC = 68–118 and φCS = 66–71 were obtained for the three most stable conformers with gauche orientation with respect to these bonds. Some conclusions of this work were presented in a short communication in Russ. J. Phys. Chem. 2005, 79, 1701.  相似文献   

6.
Venkatesh G  Singh AK 《Talanta》2005,67(1):187-194
2-{[1-(3,4-Dihydroxyphenyl)methylidene]amino}benzoic acid (DMABA) was loaded on Amberlite XAD-16 (AXAD-16) via azo linker and the resulting resin AXAD-16-DMABA explored for enrichment of Zn(II), Mn(II), Ni(II), Pb(II), Cd(II), Cu(II), Fe(III) and Co(II). The optimum pH values for extraction are 6.5-7.0, 5.0-6.0, 5.5-7.5, 5.0-6.5, 6.5-8.0, 5.5-7.0, 4.0-5.0 and 6.0-7.0, respectively. The sorption capacity was found between 97 and 515 μmol g−1 and the preconcentration factors from 100 to 450. Tolerance limits for foreign species are reported. The kinetics of sorption is fast as t1/2 is ≤5 min. The chelating resin can be reused for 50 cycles of sorption-desorption without any significant change (<1.5%) in the sorption capacity. The limit of detection values (blank +3 s) are 1.12, 1.38, 1.76, 0.67, 0.77, 2.52, 5.92 and 1.08 μg L−1 for Zn(II), Mn(II), Ni(II), Pb(II), Cd(II), Cu(II), Fe(III) and Co(II), respectively. The enrichment on AXAD-16-DMABA coupled with monitoring by flame atomic absorption spectrometry (FAAS) is used to determine all the metal ion ions in river and synthetic water samples, Co in vitamin tablets and Zn in milk samples.  相似文献   

7.
2-(2-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide radical 2 and the 2-[2-(N-alkyl)-pyrid-inium] derivatives (3a and 3b) were synthesized and characterized by elemental analysis, melting points, and spectroscopy. The density functional theory (DFT) was used in order to obtain the structures and electronic properties of the new nitronyl nitroxide radicals. Modified reaction procedures of the intermediates are described with better yield and purity of the final products. The magnetic properties of the compounds 2, 3a, and 3b are predicted for the first time using a simple model of charge transference, in the framework of the molecular orbital calculations. The obtained results show that the substituent at the central carbon atom of the imidazoline is important to determine the spin distribution and consequently the nature of the magnetic interaction.  相似文献   

8.
Reactions of equimolar quantities of potassium 2-{[(2Z)-3-hydroxy-1-methyl-2-butenylidene]amino}acetate, with R n SnX4?n (R: benzyl– and n=2 or 3) in methanol yielded products of compositions LHSn(PhCH2)3 and LSn(PhCH2)2, respectively. The complexes were characterized by microanalysis, IR, NMR (1H, 13C, 119Sn) and 119mSn Mössbauer spectroscopy. A full characterization of the structure of the complex, tribenzyl{2-{[(2Z)-3-hydroxy-1-methyl-2-butenylidene]amino}acetato}tin(IV), was carried out by single crystal X-ray crystallography. The compound exists as centrosymmetric dimers in which two ligand molecules bridge the two tin centres. Each of the tin atoms in the dimeric unit is five coordinate in an approximately trigonal bipyramidal configuration, with carbon atoms in the equatorial positions and oxygen atoms arranged axially.  相似文献   

9.
以对苯二酚和乙醇胺为原料,直接合成2,5-二(2-羟乙氨基)-1,4-苯醌,并对产物进行红外、紫外、质谱及核磁表征.采用正交设计法对实验条件进行优化,乙醇为溶剂,对苯二酚和乙醇胺物质的量比为1∶5,在50℃下,反应2h,最高产率达到72.8%.产物为针状晶体,纯度较高.  相似文献   

10.
This study presents the development of an original electrode, employing 6-methy-4-{[1-(1H-pyrrol-2-yl)methylidene]amino}-3-thioxo-3,4dihydro-1,2,4-triazin-5(2H)-one (PMTO) as a suitable ionophore. Interestingly, the electrode performance provided a very good response for Yb3+ in a wide concentration range (from 1.0 × 10−6 to 1.0 × 10−1 mol L−1) with a detection limit of 4.6 × 10−7 mol L−1 and a slope of 19.5 ± 0.3 mV per decade of Yb3+ concentration. Furthermore, it possessed a fast response time of about 10 s and it functioned in the pH range of 3.3-8.0 with a usage of at least 2 months without observing any deviations. Noticeably, the proposed electrode revealed an excellent selectivity for Yb3+ over a broad variety of alkali, alkaline earth, transition and heavy metal ions. The practical applicability of the electrode was demonstrated by its utilization as an indicator electrode in the potentiometric titration of Yb3+ ions with EDTA and in the determination of F in mouth wash samples. Additionally, it was also applied for the determination of Yb3+ ions in binary mixtures.  相似文献   

11.
A new, simple, rapid, and sensitive spectrophotometric method has been developed for the determination of nitrophenols [picric acid (PA); dinitrophenols (DNP)] in wastewater samples. The method is based on the reaction of nitrophenols with 2-[(E)-2-(4-diethylaminophenyl)-1-ethenyl]-1,3,3-trimethyl-3 H-indolium chloride reagent to form the colored ion associates, which are extracted by organic solvents. The molar absorptivity of the ion associates of PA with the investigated reagent ranges from 8.3×104 to 11.3×104 L mol–1 cm–1, depending on the extractant. Because only PA is extracted in an acidic medium with the investigated reagent, but both PA and DNP are extracted in an alkaline medium, it is possible to determine both substances in a mixture. Appropriate reaction conditions have been established. The absorbance of the colored extracts obeys Beers law in the range of 0.04–4.58 mg L–1 PA, 1.0–18.4 mg L–1 2,4-DNP and 1.2–14.7 mg L–1 2,6-DNP, respectively. The limit of detections, calculated from a blank test (n=10; P=0.95), are 0.05 mg L–1 PA, 0.9 mg L–1 (2,4-DNP), and 1.1 mg L–1 (2,6-DNP), respectively.  相似文献   

12.
1 INTRODUCTION Phthalimide and its derivatives are synthetic mate- rials, which are widely used as important chemical intermediates of biosensors[1] and many drugs such as Citalopran[2], luminal[3], Beta-Lactam[4] and the No. three generation quinolones[5], and they have been identified as active groups of some drugs and chemical luminescence reagents[6, 7]. Tert-butyl 4- [(E)-4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)-1- butenyl] benzoate is an intermediate of a new type of insulin sen…  相似文献   

13.
研究了以2-羟基-4-甲氧基苯甲醛和2-氨基-6-甲基吡啶为原料合成新型席夫碱化合物5-甲氧基-2-[(E)-(6-甲基吡啶-2-亚氨基)甲基]苯酚的方法。当2-羟基-4-甲氧基苯甲醛与2-氨基-6-甲基吡啶摩尔比为1∶1.6,反应时间为6 h,反应温度为75℃时,反应产率最高。采用元素分析、UV-Vis、IR、1H NMR、X-射线单晶衍射等方法进行结构表征。该化合物为单斜晶系,空间群P21/c,a=1.1886(3)nm,b=0.65948(16)nm,c=1.6897(4)nm,β=108.505(3)°,V=1.2560(5)nm3,Dc=1.281 g·cm-3,Z=4,F(000)=512,μ=0.087 mm-1,R1=0.0477,wR2=0.1342。通过π···π堆积和分子内氢键O2-H2···N1、C8-H8A···N2形成较稳定的晶体结构,并具有蓝色荧光。  相似文献   

14.
A method has been developed for the reaction of 2-cyanomethylbenzoic acid with N-methylanthranilic acid to give 2-[(1-methyl-4-oxo-1,4-dihydro-2-quinazolin-2-yl)methyl]benzoic acid, its esters were synthesized. The spectroscopic chracteristics of the isomeric compounds have been studied and compared in solution and in the solid state. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1532–1538, October, 2007.  相似文献   

15.
LI  Guohua  YANG  Hong 《中国化学》2009,27(10):2055-2060
Ten methyl 2‐methoxyimino‐2‐{2‐[(substituted benzylidene)aminooxymethyl]phenyl}acetate and 2‐methoxy‐ imino‐2‐{2‐[(substituted benzylidene)aminooxymethyl]phenyl}‐N‐methylacetamide derivatives were synthesized. Structures of the new compounds were characterized by IR, 1H NMR and GC‐MS data. These compounds at 10 µg/mL were tested in vitro against five pathogenic fungi, namely, Sclerotonia, Botrytis cinerea Pers, Gibberella zeae, Rhizoctorua solani and Pyricularia oryzae. Compounds G5 , G6 , G7 and G8 showed potent antifungal activities against Botrytis cinerea Pers, G7 against Gibberella zeae and G7 , G8 against Rhizoctorua solani, respectively.  相似文献   

16.
在乙醇体系中,由主配体4-[(1,3-二氧代丁基)氨基]苯甲酸(H2L,C11H11NO4)、稀土硝酸盐及辅助配体邻菲啰啉(phen)反应合成了两个系列8个配合物[Ln2(L)3(H2O)4]n(Ln=Sm(1),Eu(2),Tb(3),Dy(4));[Ln2(NO3)2(L)2(phen)2]n(Ln=Sm(5),Eu(6),Tb(7),Dy(8))。用元素分析、红外光谱、摩尔电导、热重分析进行表征,确定了产物的化学组成,推断了相应的结构。测定了室温时固体产物的激发和发射光谱,结果表明:由主辅配体共同配位的三元配合物的发光强度好于无辅助配体参与的二元配合物。测定了三元配合物的荧光寿命,其中铕和铽配合物显示较长的荧光寿命。  相似文献   

17.
1 INTRODUCTION The sulfonylurea herbicides are characterized by broad-spectrum weed control at very low use rates (c.2~75g ai ha-1), good crop selectivity and very low acute and chronic animal toxicity (acute oral LD50 to rat >4000 mg/kg)[1]. They are e…  相似文献   

18.
A series of novel N-[(1-aryl-3-phenyl-pyrazol-4-yl)methylene]-2-(halo-o-hydroxyphenyl)hydrazide derivatives was synthesized and the antibacterial activity of each of them was evaluated. The supposed reaction mechanism of acquiring compounds 3a—3d is that catalytic activity is enhanced by the electron-donating groups of the first phenyl ring while decreased by electron-withdrawing groups of that ring. The result of preliminary bioassay shows that the lowest minimal inhibitory concentration(MIC) of the title compounds against Escherichia coli is 2 μg/mL. MIC values against Monilia albican and Staphlococcus aureus are as low as 4 μg/mL. They will be a series of potential antibacterial compounds against fungi and gram-negative bacteria.  相似文献   

19.
The He1 photoelectron (PE) spectra of both 2(5H) furanone and itstrans-chair-dimeric-compound (t-c-DFN) are reported. The assignment of the PES bands is made on the basis of band shapes, the PES results of the molecules which have the similar atomic groups, and the restricted Hartree-Fock (RHF) calculations for the molecules studied. From the results of both PES experimental and theoretical calculations, it is proved that the ionization potential (IPS) of the HOMO for the dimeric-compound is lower than that of the HOMO for the monomer. And the total energy computed for thet-c-DFN is the lowest in the four possible configurations of dimeric-compounds of 2(5H) furanone. Therefore the synthesis oft-c-DFN is also the easiest. Project supported by the National Natural Science Foundation of China.  相似文献   

20.
Reactions of sodium 5-[(E)-2-(aryl)-1-diazenyl]quinolin-8-olates (LH, where the aryl group is an R-substituted phenyl ring such that for L1H: R = H; L2H: R = 2′-CH3; L3H: R = 3′-CH3; L4H: R = 4′-CH3; L5H: R = 4′-OCH3 and L6H: R = 4′-OC2H5) with Ph3SnCl in a 1:1 molar ratio yielded complexes of composition Ph3SnL. The complexes have been characterized by 1H, 13C, 119Sn NMR, IR and 119mSn Mössbauer spectroscopic techniques in combination with elemental analyses. The crystal structures of Ph3SnL1 · 0.5C6H6 (1), Ph3SnL2 (2), Ph3SnL5 · C6H6 (5) and Ph3SnL6 · 0.5C6H6 (6) were determined. The results of the X-ray studies indicated that the benzene solvated compounds 1, 5 and 6 are distorted square pyramid, with one of the phenyl C atoms in the apex while the ligand arrangement around central Sn atom in 2 is distorted trigonal-bipyramidal, with a phenyl C and the oxinato N atoms in axial positions.  相似文献   

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