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1.
In order to obtain chromosome preparations from early-developing embryos of Anilocra physodes, a squash technique has been successfully employed. Results gathered after exposure of this material to bis[dimethyltin(IV)chloro]protoporphyrin IX {[(CH3)2SnCl]2 - Protoporphyrin IX} solutions at different exposure times suggest that this chemical complex is capable of producing abnormal metaphase and anaphase figures in proportion to its concentration and not to exposure length. Essentially, all of the chromosome abnormalities are classifiable as chromosome fragments mainly observed at the metaphase stage; chromosome bridges; and large decondensed chromosome regions.  相似文献   

2.
The new rigid bicyclic AMPP((S)-TIAMPP) has been synthesized from the corresponding Ticol and Ph2PCI. The application of (S)-TIAMPP in Rh-catalyzed asymmetric hydrogenation of α-dehydroamino acids derivatives has been examined. Up to 93% ee was obtained.  相似文献   

3.
本文报道了用 PSO+P_(350)二元协同萃淋树脂色层法分离、富集、测定矿石的金。研究了该树脂的吸附性能,其饱和吸附容量为116mg Au/g 树脂。进行了柱上操作,并对树脂吸附金的机理作了探讨。  相似文献   

4.
To develop low-cost and efficient dye-sensitized solar cells (DSSCs), we designed and prepared three homoleptic Cu(I) complexes with asymmetric ligands, M1, M2, and Y3, which have the advantages of heteroleptic-type complexes and compensate for their synthetic challenges. The three copper(I) complexes were characterized by elemental analysis, UV-vis absorption spectroscopy, and electrochemical measurements. Their absorption spectra and orbital energies were evaluated and are discussed in the context of TD-DFT calculations. The complexes have high VOC values (0.48, 0.60, and 0.66 V for M1, M2, and Y3, respectively) which are similar to previously reported copper(I) dyes with symmetric ligands, although their energy conversion efficiencies are relatively low (0.17, 0.64, and 2.66%, respectively).  相似文献   

5.
薛蒙伟  潘兆瑞  石翛然  邵阳 《应用化学》2015,32(10):1127-1133
用扩散法合成了一种新的银配合物—[Ag(mtyaa)]2·5(H2O)(mtyaa=2-(5-甲基-1,3,4-噻二唑)-硫乙酸阴离子),用X射线单晶衍射仪测定了配合物的单晶结构,并对它进行了元素分析、红外光谱、热重、荧光和粉末X射线衍射等表征。 配合物属于三斜晶系,P1ˉ空间群。 晶胞参数为:a=0.8473(4) nm,b=1.0620(5) nm,c=1.2055(6) nm,α=102.321(8)°,β=99.951(9)°,γ=96.298(9)°,V=1.0317(9) nm3,Z=2,Dc=2.203 g/cm3,F(000)=676,R1=0.0670,wR2=0.1558。 在配合物中mtyaa配体采取两种配位模式。 四配位的银离子通过mtyaa的端机氮原子和硫原子桥连形成一个二维结构,此二维结构又通过大量的氢键形成三维网络结构。 本文研究了标题配合物的荧光性能。 荧光测试表明,配合物在350 nm波长的光激发下在467和492 nm出现了两个弱发射峰,在530 nm处出现了一个较宽的发射带。  相似文献   

6.
The complex [(CF3-BINAP(O))Rh(COD)][ClO4]·Et2O(2,CF3-BINAP(O)=2-{bis[3,5-bis(trifluoromethyl)phenyl]phosphino}-2-{bis[3,5-bis(trifluoromethyl)phenyl]phosphinyl}-1,1-binaphthyl, COD=1,5-cyclooctadiene) was obtained directly from the reaction of CF 3-BINAP(O) ligand with [Rh(COD)][ClO4]. Complex 2 has been characterized by single-crystal X-ray diffraction. The crystal adopts space group P21/n with a=19.0727(4), b=15.6275(4), c=22.3039(6), β=112.3570(10)°, V=6148.2(3)3 , Z=4, Dc=1.693 g/cm3 , F(000)=3144, μ(MoKα)=0.500 mm-1 , the final R=0.0947 and wR=0.2501. Structural studies reveal that Rh(I) is coordinated by one oxygen and one phosphorus in the same ligand. Asymmetric hydrogenation of acetami- docinnamic acid with compound 2 was also evaluated.  相似文献   

7.
A fluorescent cobalt(Ⅱ) complex, 1 [Co(H2bibim)2(5-nipa)], for the recognition of cations and small molecules constructed with 5-nitroisophthalic acid (5-H2nipa) and 2,2-biben-zimidazole(H2bibim) has been synthesized by hydrothermal methods and structurally characterized by elemental analysis, IR spectroscopy, PL and single-crystal X-ray diffraction. The cobalt units are six-coordinated by two H2bibim ligands and one 5-nitroisophthalic acid group, which are further connected into a three-dimensional (3D) network by intermolecular hydrogen bonds. Complex 1 exhibits fluorescence and thus has detection capabilities for different cations and small solvent molecules in the solution state at room temperature.  相似文献   

8.
A new chiral multidenate ligand (S,S)-1,7-bis(4-benzyloxazolin-2-yl-methyl)-1,7-diaza-12-crown-4 1 has been synthesized and used as ligand in the copper catalyzed asymmetric cyclopropanation of 1,1-diphenylethylene.  相似文献   

9.
Abstract

A new asymmetric tetradentate Schiff base, bis(5-methoxysalicylidene)-4-methylbenzene-1,2-diamine), H2L, and its Ni(II) complex were prepared and characterized using elemental analyses (CHN), FTIR, UV–Vis, 1H NMR, and 13C{1H} NMR spectroscopic techniques, and crystal structures of both were determined by X-ray crystallography. For both ligand and Ni(II) complex, density functional theory calculations to find geometry parameters, IR frequencies, electronic properties, and natural bond orbital analysis (NBO) were done with M062X method and Def2-TZVP basis set. All calculated data are consistent with the experiments. NBO data for the Ni(II) complex show that the main type of transition in UV-Vis is interligand charge-transfer, which is assigned as π-π*.  相似文献   

10.
合成并通过单晶衍射、元素分析及红外光谱表征了配合物[Cu4(L)2(CH3O)2(CH3OH)4(SO42]SO4·6CH3OH(1)的结构(L为3-乙基-2-乙酰吡嗪双缩水合肼)。单晶衍射结果表明,在配合物1中,每个Cu(II)离子与来自半个腙配体的2个N原子和分别来自配位甲醇、桥联甲氧基及2个不同硫酸根的单齿配位和桥联氧原子配位,形成扭曲的八面体配位构型。4个Cu(II)离子通过对称操作形成理想的平面四核铜簇。此外,荧光光谱表明配合物1与DNA的相互作用强于配体L。  相似文献   

11.
Two novel chiral Br?nsted acids 3b and 3c were prepared without involving the complexity of Suzuki coupling. Catalyst 3c bearing two additional hydroxyl groups at 3 and 3′ positions of axially chiral 1,1‐binaphthalene‐2,2′‐diol phosphoric acid was applied in a model Mannich reaction to afford β‐amino ester in high yield (92%) and enantiomeric excess (91%) at low reacting temperature of ?40°C. In addition, those β‐amino ester derivatives with high yields and excellent enatioselectivities were obtained in the presence of catalyst 3c under the above condition.  相似文献   

12.
吕海燕 《有机化学》2009,29(2):234-238
以四硫富瓦烯(TTF)和氯甲基噻吩为原料, 在碱性条件下合成了一个新的基于TTF大环分子1. 化合物1的结构经元素分析、核磁共振氢谱、质谱和X衍射单晶结构确认. 化合物1属单斜晶系, 空间群P2(1)/n, 晶胞参数: a=0.97220(19) nm, b=1.2366(3) nm, c=1.6051(3) nm, β=95.41(3)°, V=1.9211(7) nm3, Z=2, Dc=1.621g/cm3, F(000)=960, μ=1.032 mm-1, R=0.0333, wR=0.1000 [I>2σ(I)]. 循环伏安结果显示化合物1有两对氧化还原峰, 氧化还原过程不可逆.  相似文献   

13.
The TaCl5/In system was found to be a new reagent for reducing a wide range of structurally diverse sulfoxides to the corresponding sulfides with high yields under mild conditions. This protocol is chemoselective and tolerates several functional groups, such as Br, Cl, OCH3, CHO, and CH = CH2.  相似文献   

14.
丁丹丹  张秀梅  刘结平 《结构化学》2014,33(7):1037-1042
One compound with N-(4-pyridylmethyl)imidazole liand, [Co(pyim)2(N3)2]n 1(pyim = N-(4-pyridylmethyl)imidazole), was synthesized and structurally characterized. Compound 1 crystallizes in triclinic, space group P21/c with a = 8.090(3), b = 16.109(3), c = 8.590(3), B= 117.800(12)o, V = 990.3(5) A3, Z = 2, Mr = 461.37, Dc = 1.547 g/cm3, F(000) = 474, μ = 0.901 mm-1, the final R = 0.0381 and wR = 0.0950 for 1581 observed reflections with I 2A(I). In this compound, the unique Co(Ⅱ) resides at a crystallographic inversion center and exhibits an octahedral coordination geometry. The adjacent Co(Ⅱ) ions are connected by the pyim ligands to form a 2D layer structure. The layers are stacked in an ABAB mode and reinforced by the weak interlayer C–H···N hydrogen bonds and π-π stacking to give a 3D architecture. The thermal property and electrochemical property of compound 1 have also been studied.  相似文献   

15.
D(-)-酒石酸二乙酯(1)分别与2-氨甲基吡啶和4-氨甲基吡啶反应,合成了D(-)-二吡啶甲基酒石酸酰胺2和3.分别以1~3为手性配体与钛酸异丙酯配合,催化过氧化氢异丙苯(CHP)不对称氧化埃索美拉唑前体(Eso-I)合成埃索美拉唑.结果表明,由配体2或3构成的催化体系在埃索美拉唑合成上显示出较高的催化活性和对映选择性.例如,当以2为配体,甲苯为溶剂,在优化的条件下进行反应时,Eso-I的转化率达84.7%,埃索美拉唑的选择性达91.8%,对映体过量值达89.0%.  相似文献   

16.
Fostriecin(CI-920) 11 a potential anticancer agent presently in phase I clinical trials at NCI is a novel phosphate ester produced by Streptomyces pulveraceus. Scheme 1 1 2 3 5 4 Synthesis of C10 epimer of compound 1 had been reported by Just G2. during the determination of its structure. On the basis of Just’s synthesis, a revised retro-asymmetric synthetic route of Fostriecin (scheme 1) was designed here of which compound 3 was synthesized from 5 with C3 in R configuration correspondi…  相似文献   

17.
由(1R,2S)-麻黄碱制得了五个新的手性硼杂(口恶)唑烷1~5,它们催化甲硼烷不对称还原苯乙酮,获得了高产率的具有38.5~72.4%e.e.的R-1-苯基乙醇。讨论了催化剂的结构-活性关系及反应参数(催化剂用量、反应温度)对还原反应对映选择性的影响。  相似文献   

18.
Thermoanalysis study has been carried out on the complex of bis[1-(2-thienyl)-4,4,4-trifluoro-butanedione- 1,3]copper(Ⅱ) and its adducts with pyridine, 2,2′-bipyridine, quinoline and dimethyl sulfoxide in a dynamic ni-trogen atmosphere by simultaneous TG-DTG-DSC technique. The experimental results showed that the decomposi-tion modes of the solvent molecules were various according to the different structures of the complex, in general, the decomposition of them was ahead of the decomposition of the ligand 1-(2-thienyl)-4,4,4-triflurobu- tanedione-1,3. Among them the adduct with 2,2-bipyridine showed a quite unique thermal behavior. Several methods have been jointly used to study the kinetics of all the thermal decomposition stages for title compounds, which showed that the evolution of the solvent molecules was controlled mainly by Rn mechanism (or Am mechanism for 2,2-bipyridine adduct) with lower activation energy; while the release of 1-(2-thienyl)-4,4,4-trifluro-butane- dione-1,3 was gove- rned by D2 or D3 mode with higher activation energy.  相似文献   

19.
Summary: High‐resolution FT‐IR spectroscopy has been used for the first time to characterize the variation of the unit cell dimensions of high‐density polyethylene (HDPE). In combination with the unit cell parameters of HDPE measured at different temperatures by Swan using wide‐angle X‐ray diffraction, the relationship between the rocking band shift (730 cm−1) and the change of the unit cell volume of HDPE has been established.

High‐resolution variable‐temperature FT‐IR spectra of HDPE rocking bands with decreasing temperature.  相似文献   


20.
The organotin(Ⅳ) compound (p-NCC6H4CH2)4Sn was synthesized by the reaction of p-cyanobenzyl chloride with tin. The compound was characterized by elemental analysis, IR, 1H NMR, and the crystal structure was determined by X-ray single crystal diffraction. The crystal belongs to triclinic, space group P1 with a=0.894 1(4) nm, b=0.977 9(4) nm, c=1.796 8(8) nm, V=1.386 9(11) nm3, Z=2, Dc=1.397 Mg·m-3, μ(Mo )=0.948 mm-1, F(000)=588, R1=0.046 9, wR2=0.101 4. The tin atom adopts a distorted tetrahedral coordination geometry. CCDC: 272939.  相似文献   

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