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1.
(R)—四氢噻唑—2—硫酮—4—羧酸的合成及其晶体结构   总被引:3,自引:3,他引:3  
由L-半胱氨酸盐酸盐与二硫化碳在NaOH及CuSO4.H2O存在下反应得到(R)-四氢噻唑-2-硫酮-4-羧酸,「α」^20D-87.5°,产率66%。用X射线衍射法测得其晶体结构,属正交晶系,Pz1z1z1空间群,晶体学参数:α=0.5029(2)nm,b=0.77499(5)nm,c=1.6300(5)nm,V=0.6350(5)nm^3,Z=4。用分子轨道方法研究了该化合物的电子结构,得到其  相似文献   

2.
铜(Ⅱ)和锌(Ⅱ)分别在0.1mol/LKH2PO4-Na2HPO4缓冲溶液(pH6.5)和0.25mol/LNH4Cl溶液中,与氟哌酸形成良好的络合吸附波,峰电位分别为-0.26V和-1.28V(vs.SCE),络合比分别为1:3和1:2,峰电流与铜(Ⅱ)和锌(Ⅱ)的浓度均在4.0×10^-7~5.0×10^-6nol/L范围内呈线性关系,检测限分别为7.0×10^-8和5.0×10^-8mol  相似文献   

3.
本文报道了一个灵敏度高,选择性好的测定痕量钍的新光度分析法。在聚乙烯醇存在下,钍钼杂多酸和丁基罗丹明B形成离子缔合物,其适宜条件为CHClO4=1.3MOL/L,CMoO^2-4=6.8×10^-4mol/L,CBRB=2.7×10^-5mol/L,PVA0.08%。  相似文献   

4.
硼掺杂多晶金刚石薄膜电极的电化学特性   总被引:1,自引:0,他引:1  
朱建中  许春芳 《分析化学》1995,23(7):824-827
用循环伏安法和恒电位法研究了硼掺杂多晶金刚石薄膜电极(DFE)的若干电化学特性。电极面积4×4mm^2。在0.1mol/L KCl,NaNO3,NaOH和KH2PO4+Na2HPO4(pH=6.86)电解质溶液中电势窗口均为-500 ̄+800mV;而在0.1mol/L HCl和H2SO4溶液中电势窗口为-200 ̄+1100mV.K3Fe(CN)6的氧化峰电位为+500mV,与Pt电极测量相同;校正  相似文献   

5.
范鸿章  林俊兰 《分析化学》1995,23(4):419-422
TPPC在0.08mol/LCH3COONa和0.4mol/LCH3COOH(NaAc-HAc下同)底液条件下,在电位-1.57V附近产生一尖锐的导数波,峰高在3.7×10^-6-5.6×10^-5mol/L范围内呈线性关系,同时,讨论了极谱波的性质及电极反应机理。  相似文献   

6.
宋俊峰  高雅芳 《分析化学》1995,23(4):438-441
本报道一种测定哌仑西平的单扫描示波极谱法,在0.1mol/LNH4Cl-NH3.H2O(pH8.0±0.1)缓冲液中,哌仑西平有一极谱还原波,其峰电位为-1.51V(vs.SCE),其一阶导数峰高与哌仑西闰浓度在6.6×10^-7-4.6×10^-6mol/L(r=0.9981)和6.6×10^-6-1.6×10^-5mol/L(r=0.9991)范围内有线性关系,检测限为3.4×10-7mol  相似文献   

7.
硼氢化钠还原法制备四羰基钴钠及羰基化反应   总被引:4,自引:1,他引:4  
李光兴  蔡晓江 《合成化学》1995,3(3):263-266
在常温压下,用NaBH4作还原剂,由CO与CoCl2反应制备Na[Co(CO)4],其最佳的原料配比为NaBH4:CoCl2=2.5:1,反应温度为0-5℃,反应时间为2h。产物经IR光谱鉴定,在1893cm^-1处有一强吸收峰,此峰为[Co(CO)4]^-络合物离子中M-CO的特征吸收峰。  相似文献   

8.
氧氟沙星的单扫描示波极谱分析   总被引:8,自引:0,他引:8  
张淑敏  赫春香 《分析化学》1997,25(10):1177-1180
报道了一种灵敏的氧氟沙星测定方法-一阶导数单扫示波极谱分析,同时研究了它的极谱波性质和电极反应机理,在pH6.0的KH2PO4-Na2HPO4(PBS)底液中,氧氟沙星产生一个灵敏的还原峰,Ep=-1.55V(vs.SCE),其导数峰高与浓度在1.0×10^-5~4.6×10^-7mol/L范围内呈良好的线性关系,相关系数r=0.9996,检测下限为2.4×10^-7mol/L,可用于氧氟沙星片剂  相似文献   

9.
陈邦林  陈克 《应用化学》1995,12(1):13-17
合成了4种锰(Ⅲ)-苯甲酰丙酮缩乙二胺-有机碱配合物:Mn(bzacen)LClO4.(L为哌嗪,吡啶,γ-甲基吡啶和乙腈)。测定了配合物[Mn(bzacen)(CH3CN)ClO4]的结构,晶体属正交晶系。空间群Pnma。晶胞参数:a=0.9077(1),b=1.5563(1)nm,c=1.7205(2)nm,V=2.4305nm^3,Z=4,Dc=1.48g/cm^3,Dm=1.49g/cm^  相似文献   

10.
四氢糠基环戊二烯稀土氯化物的合成及表征   总被引:1,自引:0,他引:1  
报道了四氢糖基环戊烯基稀土氯化物的合成,用元素分析,红外光谱,质谱和核磁共振谱表征这类化合物的组成为(C4H7COH2C5H4)2LnC1(Ln=Nd,Gd,Dy,Er),测定了(C4H7OCH2C5H4)2DyCl的晶体结构属正交晶系,P2,2121空间群,晶胞参数:α=1.1809(3)nm,b=1.2149(4)nm,c=1.3377(5)nm,z=4,Dc=1.72g/cm^3,R=0.0  相似文献   

11.
锌锡双金属掺杂MCM-41的合成及表征   总被引:3,自引:0,他引:3  
以硅酸钠为硅源, 锡酸钠,硝酸锌为金属源,十六烷基三甲基溴化铵为模板剂,采用直接水热合成法合成出了锌锡双金属同时掺杂的介孔MCM-41。通过ICP﹑XRD、TG-DTA﹑FTIR﹑HRTEM以及BET等技术对材料的结构和性质进行了表征。结果表明,合成的材料具有典型的六方介孔结构,比表面高,孔分布窄,热稳定性较高,且锌锡可能进入介孔MCM-41骨架中。该材料对苯酚羟基化反应具有良好的催化性能,双金属修饰MCM-41催化活性明显优于单组分掺杂。  相似文献   

12.
The hydrothermal reaction of the tricarboxylate ligand 5‐(carboxymethoxy)isophthalic acid (H3L) with ZnII, CdII, and SnII salts in the presence of the bisbenzoimidazole coligand 1, 3‐bis(benzimidazol‐2‐yl)‐2‐oxapropane (bbop) afforded the coordination polymers, [Zn(HL)(bbop)]n ( 1 ), [Cd(HL)(bbop)]n ( 2 ), and {[H2(bbop)][Sn2L2]}n ( 3 ). The complexes were characterized by elemental analyses, IR spectroscopy, single‐crystal X‐ray diffraction analyses, thermogravimetric analyses, and fluorescence properties. The structures of complexes 1 and 2 are constructed by 1D chains and show strong blue luminescence emission. The structure of complex 3 is a 2D anionic dilayer, and shows a vase‐like porous structure occupied by the bulky [H2(bbop)]2+ cation, which is an uncommon structural feature in transition metal coordination polymers. The three complexes are further connected by hydrogen bonds to form 3D supramolecular architectures.  相似文献   

13.
The three new ternary phases Na16Zn13.54Sn13.46(5) (I), Na22Zn20Sn19(1) (II), and Na34Zn66Sn38(1) (III) were obtained by direct fusion of the pure elements and characterized by single crystal X-ray diffraction experiments: I, Ibam, Z=8, a=27.401(1), b=16.100(1), c=18.431(1) Å, R1/wR2 (all data)=0.051/0.088; II, Pnma, Z=4, a=16.403(1), b=15.598(1), c=22.655(6) Å, R1/wR2 (all data)=0.038/0.071; III, Rm, Z=3, a=16.956(1), c=36.861(1) Å, R1/wR2 (all data)=0.045/0.092. The structures consist of complex 3D cluster networks made of Zn and Sn atoms with the common motif of Kagomé nets of icosahedra. Additionally to the new heteroatomic {Zn12−xSnx} icosahedra that are omnipresent, triangular units, cages, and pairs of triply fused icosahedra fill the cavities of the Kagomé nets in compounds I, II, and III, respectively. Whereas I crystallizes in a new structure type, II and III have structural analogs in trielide chemistry. All three compounds closely approach the electron numbers expected for valence compounds according to the extended 8-N rule. The concept of achieving an isovalent situation to triel elements by combination of electron poorer and richer elements and the readily mixing of Zn and Sn allow the formation of icosahedral and triangular clusters without the participation of a group 13 element.  相似文献   

14.
Although the addition of crotyl or prenyl organometallic reagents has certainly found application in organic synthesis, the use of other non-symmetric allylic organometallic reagents has not received much attention. In part this is due to potential problems in controlling the regioselectivity of the addition products. We have noted that the tin and zinc reagents derived from 2-bromomethylcyclohexenone afford the complementary α and γ addition products, respectively. These conditions work for the reaction with a range of aldehydes, affording the products in good to modest yield.  相似文献   

15.
Synthesis and Solid State Structure of the Coordination Polymer {Zn[Sn(CH2SMe)4]0.5Cl2}n The tin compounds Sn(CH2SMe)4 and Sn(CH2PPh2)4 are accessible from reaction of SnCl4 with LiCH2SMe and LiCH2PPh2, respectively. X‐ray quality crystals of Sn(CH2PPh2)4 (tetragonal, ) are obtained from a benzene solution at 4 °C. The lithium methanide [Li(PMDTA)CH2PPh2], which was a starting material in the synthesis of Sn(CH2PPh2)4 crystallized from a mixture of diethyl ether and pentane at ?20 °C in the monoclinic space group P21/c. The coordination polymer {Zn[Sn(CH2SMe)4]0.5Cl2}n was synthesized from Sn(CH2SMe)4 and ZnCl2 in benzene. The solid state structure of this coordination polymer reveals that {Zn[Sn(CH2SMe)4]0.5Cl2}n possesses an infinite [Zn‐SMe‐CH2‐Sn‐CH2‐SMe‐]‐chain as its backbone (monoclinic P21/c).  相似文献   

16.
17.
In this work, three heavy metals (Cu(II), Pb(II) and Zn(II)) in wide potential window were simultaneously detected on tin film/gold nanoparticles/gold microelectrode (Sn/GNPs/gold microelectrode) by the method of square wave stripping voltammetry. The Sn/GNPs/gold microelectrode was fabricated by in situ plating of a Sn film on a gold nanoparticles (GNPs) modified gold microelectrode. The influence of hydrogen overflow on stripping of Zn(II) on the gold microelectrode was reduced by modification of GNPs, which made the stripping potential of target metals shift positively. The interference of sulfhydryl groups was reduced and the selectivity of the microelectrode was improved due to the addition of Sn in the detection solution. After accumulation at ?1.4 V for 300 s in acetate buffer solution (0.1 mol L?1, pH 4.5), the Sn/GNPs/gold microelectrode revealed a good linear behavior in the examined concentration ranges from 5 to 500 µg L?1 for Cu(II) and Pb(II), and from 10 to 500 µg L?1 for Zn(II), with a limit of detection of 2 µg L?1 for Cu(II), 3 µg L?1 for Pb(II) and 5 µg L?1 for Zn(II) (S/N=3). When compared with a Sb/GNPs/gold microelectrode and a Bi/GNPs/gold microelectrode, the Sn/GNPs/gold microelectrode showed the best stripping performance to Cu(II), Pb(II) and Zn(II). As a new type of environment‐friendly electrode, the Sn/GNPs/gold microelectrode has potential applications for detection of heavy metals.  相似文献   

18.
Four organic–inorganic crystals, [(HL1)2(ZnCl4)]·H2O (1) (L1?=?2-methylquinoline), [(HL1)2(CuCl4)] (2), [(HL2)2SnCl6] (3) (L2?=?6-bromobenzo[d]thiazol-2-amine), and [(HL3)FeCl4] (4) (L3?=?5,7-dimethyl-1,8-naphthyridine-2-amine), derived from N-containing aromatic Brønsted bases and metal(II) chlorides (zinc(II) chloride, copper(II) chloride dihydrate, tin(II) chloride dihydrate, and iron(III) chloride hexahydrate) were prepared at room temperature and characterized by IR, X-ray structure analysis, elemental analysis, and TG analysis. The crystals are built up by perchlorometallates (Zn, Cu, Sn, and Fe) associated with organic cations through multiple non-covalent associations. X-ray diffraction analysis reveals that 1 and 2 have 3-D network structures built from hydrogen bonds between the cations and chlorometallates. Water molecules play an important role in structure extension in 1. Anhydrous 3 and 4 produced from 2-aminoheterocyclic derivatives display 2-D sheet structures. Arrangements of anions and cations are dominated by shape and size of cations, and also by the different structures of the chlorometallates as well as non-bonding interactions in the crystal structures. Except for 1, the other compounds are thermally stable below 240°C.  相似文献   

19.
Crystal Structure of (NH4)3SnF7: A Double Salt According to (NH4)3[SnF6]F and not (NH4)4SnF8 (NH4)3SnF7 is obtained as colourless single crystals from the reaction of NH4HF2 with tin powder at 300°C. The crystal structure (cubic, Pm3m, Z = 1, a = 602.5(1) pm at 293 K; a = 598.0(1) pm at 100 K) contains [SnF6]2? octahedra and lonesome F? ions surrounded by NH4+ cations only; it may be considered as a derivative of the Cu3Au-type of structure according to Cu3[Au]□ ?(NH4)3[SnF6]F. The F? ions of the [SnF6]2? octahedra with their Sn4+ centre in the origin of the unit cell at m3m are disordered in different ways at 293 and 100 K, respectively.  相似文献   

20.
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