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1.
采用量子化学计算方法研究了H2O2 氧化N2 生成N2O 和H2O 的机理.结果发现, H2O2 氧化N2 先通过1 个四元环过渡态形成中间体H2N2O2 分子,H2N2O2 再通过一个五元环过渡态形成N2O和H2O.根据计算得到的每步反应的活化能,得知H2O2 氧化N2 生成中间体H2N2O2 分子是整个反应的控制步骤.  相似文献   

2.
郭勇  陈庆云 《化学学报》2001,59(10):1722-1729
二氟二碘甲烷(CF2I2,1)与乙烯基乙醚和Na2S2O4在DMSO和乙醇的混合溶剂中反应得3,3-二氟-3-碘丙醛的乙缩醛[ICF2CH2CH(OEt)2](3).3在锌粉的作用下发生偶联反应生成二缩醛[(EtO)2CHCH2CF2CF2CH2CH(OEt)2](5)。缩醛3或5与烯醇硅醚在SnCl4作用下发生交叉偶联反应。3在锌粉或保险粉的引下与烯醇硅醚发生加成反应。3和5分别转化成硫缩醛ICF2CH2CH(SR)2(13),(RS)2CHCH2CF2CF2CH2CH(SR)2(14)或O,S-缩醛。13消HI得1,1-二氟乙烯衍生物。  相似文献   

3.
杂元素冠醚研究 Ⅶ.多硒杂冠醚及其钯配合物的合成   总被引:2,自引:0,他引:2  
李卫平  刘秀芳  徐汉生 《化学学报》1994,52(11):1082-1087
在碱性条件下,1,2-二硒杂环戊烷被硼氢化钠还原成双硒负离子,然后和二醇的二对甲苯磺酸酯或二氯化物缩合成环,得到六个二硒杂冠醚(2a,3a,4a,5a,6a,7a)和七个四硒杂冠醚(2b,3b,4b,5b,6b,7b,8b).同时,通过5a,5b与二氯化钯反应,合成了两个钯配合物,并讨论了其配位特征  相似文献   

4.
钾镁氯化物(硫酸盐)与脲、水体系的溶度研究   总被引:7,自引:0,他引:7  
报导了KCl-MgCl2-CO(NH2)2-H2O和K2SO4-MgSO4-CO(NH2)2-H2O两个四元体系在25℃时的溶度及其饱和溶液的折光率、密度,相应的溶度图和组成-折光率、组成-密度图.前一体系中形成3个三元化合物:MgCl2·4CO(NH2)2·2H2O、MgCl2·CO(NH2)2·4H2O和KCl·MgCl2·6H2O溶度盐份图由9支共饱线、4个四元无变点组成.四元体系的水量图、性质-组成图有类似的变化.后一体系中有2个异成份溶解化合物MgSO4·CO(NH2)2·2H2O和K2SO4·MgSO4·6H2O形成,溶度等温图由7支双饱溶度线、3个四元无变点组成.对两个体系相图的相似性和差异点进行了讨论.  相似文献   

5.
郭勇  陈庆云 《化学学报》2001,59(10):1730-1734
在四醋酸铅的催化下,二氟二碘甲烷(CF2I2,1)与四氟乙烯加成生成1,3-二碘六氟丙烷(ICF2CF2CF2I,3).3与烯烃、炔烃和丙二酸二乙酯阴离子发生电子转移反应。  相似文献   

6.
对若干线型Mo一Fe一S簇合物[Cl2FeS2MoS2FeCl2][-2](1)、[S2MoS2FeCl2]^2^-(2)、[S2MoS2Fe(SPh)2][2-](3)、[S2MoS2FeS2Fe(SPh)2][3-](4)、[S2MoS2FeS2MoS2][3-](5)、Cl2FeS2FeCl2][2-](6)、[(PhS)2FeS2Fe(SPh)2][2-](7)的红外光谱进行了研究。通过比较它们的特征频率、结构参数和金属原子的氧化态,对νMo-St、νMo-SbνFe-Sb、νFe-SPh、νFe-Cl进行了归属。并对δS-Mo-S的归属作了初步探讨。文中讨论了MoS2Fe单元中Mo原子对νFe-Sb的影响, 通过振动频率与结构关系的研究揭示其内在联系及规律性。对两条途径的亲电诱导效应进行了讨论, 并提出一个能定性标志Fe→Mo电荷迁移大小的有用参数Δν值。  相似文献   

7.
Ten polymeric silver(I) double salts containing embedded acetylenediide: [(Ag2C2)2(AgCF3CO2)9(L1)3] (1), [(Ag2C2)2(AgCF3CO2)10(L2)3]H2O (2), [(Ag2C2)(AgCF3CO2)4(L3)(H2O)]0.75 H2O (3), [(Ag2C2)(1.5)(AgCF3CO2)7(L4)2] (4), [(Ag2C2)(AgCF3CO2)7(L5)2(H2O)] (5), [(Ag2C2) (AgC2F5CO2)7(L1)3(H2O)] (6), [(Ag2C2)(AgCF3CO2)7(L1)3(H2O)]2 H2O (7), [(Ag2C2)(AgC2F5CO2)6(L3)2] (8), [(Ag2C2)2(AgC2F5CO2)12(L4)2(H2O)4]H2O (9), and [(Ag2C2)(AgCF3CO2)6(L3)2(H2O)]H2O (10) have been isolated by varying the types of betaines, the perfluorocarboxylate ligands employed, and the reaction conditions. Single-crystal X-ray analysis has shown that 1-4 all have a columnar structure composed of fused silver(I) double cages, with C2(2-) species embedded in its stem and an exterior coat comprising anionic and zwitterionic carboxylates. For 5 and 6, single silver(I) cages are linked into a beaded chain through both types of carboxylate ligands. In 7, two different coordination modes of L1 connect the silver(I) polyhedra into a chain. For 8, the mu(2)-O,O' coordination mode of L3 connects the silver(I) double cages into a chain. Compound 9 exhibits a two-dimensional architecture generated from the cross-linkage of double cages by C2F5CO2-, L4, and [Ag2(C2F5CO2)2] units. Similar to 9, 10 is also a two-dimensional structure, which is formed by connecting the chains of linked double cages through [Ag2(CF3CO2)2] bridging.  相似文献   

8.
In the quest for low-molecular-weight metal sulfur complexes that bind nitrogenase-relevant small molecules and can serve as model complexes for nitrogenase, compounds with the [Ru(PiPr(3))('N(2)Me(2)S(2)')] fragment were found ('N(2)Me(2)S(2)'(2-)=1,2-ethanediamine-N,N'-dimethyl-N,N'-bis(2-benzenethiolate)(2-)). This fragment enabled the synthesis of a first series of chiral metal sulfur complexes, [Ru(L)(PiPr(3))('N(2)Me(2)S(2)')] with L=N(2), N(2)H(2), N(2)H(4), and NH(3), that meet the biological constraint of forming under mild conditions. The reaction of [Ru(NCCH(3))(PiPr(3))('N(2)Me(2)S(2)')] (1) with NH(3) gave the ammonia complex [Ru(NH(3))(PiPr(3))('N(2)Me(2)S(2)')] (4), which readily exchanged NH(3) for N(2) to yield the mononuclear dinitrogen complex [Ru(N(2))(PiPr(3))('N(2)Me(2)S(2)')] (2) in almost quantitative yield. Complex 2, obtained by this new efficient synthesis, was the starting material for the synthesis of dinuclear (R,R)- and (S,S)-[micro-N(2)[Ru(PiPr(3))('N(2)Me(2)S(2)')](2)] ((R,R)-/(S,S)-3). (Both 2 and 3 have been reported previously.) The as-yet inexplicable behavior of complex 3 to form also the R,S isomer in solution has been revealed by DFT calculations and (2)D NMR spectroscopy studies. The reaction of 1 or 2 with anhydrous hydrazine yielded the hydrazine complex [Ru(N(2)H(4))(PiPr(3))('N(2)Me(2)S(2)')] (6), which is a highly reactive intermediate. Disproportionation of 6 resulted in the formation of mononuclear diazene complexes, the ammonia complex 4, and finally the dinuclear diazene complex [micro-N(2)H(2)[Ru(PiPr(3))('N(2)Me(2)S(2)')](2)] (5). Dinuclear complex 5 could also be obtained directly in an independent synthesis from 1 and N(2)H(2), which was generated in situ by acidolysis of K(2)N(2)(CO(2))(2). Treatment of 6 with CH(2)Cl(2), however, formed a chloromethylated diazene species [[Ru(PiPr(3))('N(2)Me(2)S(2)')]-micro-N(2)H(2)[Ru(Cl)('N(2)Me(2)S(2)CH(2)Cl')]] (9) ('N(2)Me(2)S(2)CH(2)Cl'(2-) =1,2-ethanediamine-N,N'-dimethyl-N-(2-benzenethiolate)(1-)-N'-(2-benzenechloromethylthioether)(1-)]. The molecular structures of 4, 5, and 9 were determined by X-ray crystal structure analysis, and the labile N(2)H(4) complex 6 was characterized by NMR spectroscopy.  相似文献   

9.
硫化合物与H2O2在非催化反应中的非线性行为   总被引:3,自引:0,他引:3  
硫化学反应中的非线性是近年来非线性化学研究的热点之一,我们注意到CU(11催化剂存在时H202氧化KSCN山、N。。S。0开]出现振荡或复杂振荡现象,但这两个反应的机理研究尚处在不成熟或模糊阶段*‘1,由于K盯N、*。。a0。和优(*H小氧化过程有多种价态的变化,Cu(11)催化  相似文献   

10.
中心为氨基、末端为硝基的苯乙炔树枝状分子的合成   总被引:1,自引:0,他引:1  
将固定相合成与“收敛/发散”方法相结合,合成了第一、二代苯乙炔树枝状分子.通过Heck-Cassar-Sonogashira-Hagihara偶联反应,将其中心和末端分别修饰上供电子的氨基和拉电子的硝基,得到第一、二代中心为氨基、末端为硝基的苯乙炔树枝状分子NH2-G1-(NO2)2和NH2-G2-(NO2)4.用傅里叶变换红外光谱跟踪了整个固定相合成过程.苯乙炔树枝状分子的紫外-可见吸收光谱呈现出规律性变化.  相似文献   

11.
四氯化钛-锌粉还原环化δ-酮腈是合成环戊酮的一种简便方法。在同样条件下, 由4-甲基-4-乙酰基庚二腈得到1,5-二甲基双环-[3.3.0]-2,8-辛二酮。  相似文献   

12.
用MnSO4·H2O,KSCN,六次甲基四胺(HMTA)制备出超分子化合物[Mn(NCS)2(H2O)2(HMTA)2][Mn(NCS)2(H2O)4](H2O)2,并测定了其晶体结构。该化合物由[Mn(NCS)2(H2O)2(HMTA)2],[Mn(NCS)2(H2O)4]和H2O三部分组成,每一个HMTA配体中仅有一个N原子与Mn原子配位,剩余的3个N分别与[Mn(NCS)2(H2O)4]中的H2O及结晶H2O之间形成氢键。[Mn(NCS)2(H2O)2(HMTA)2]和[Mn(NCS)2(H2O)4]之间通过N…H—O氢键边接成无限延伸的线性长链,链与链、以及链和结晶H2O之间通过七种形式的氢键构成三维结构的超分子。用Z-扫描法测定该化合物在DMF溶液中的三阶非线性光学性质,发现它具有自聚焦效应,三阶非线性折射系数n2=9.52×10^-9m^2·W^-1,非线性极化率χ^(3)=3.41×10^-12esu.  相似文献   

13.
离子型有机锡化合物的合成及其生物活性   总被引:2,自引:1,他引:1  
钟桂云  孙丽娟 《应用化学》2011,28(4):387-393
利用有机锡卤化物与有机酸在有机胺存在下反应合成了一系列离子型有机锡化合物,分子通式为[HNR3][(PhCH2)3Sn(μ2-SCH2COO)Cl]、[HNR3][Ph3Sn)3(O2CCH2CO2)2]·CH3CH2OH和[HNR3] [MeCy2ClSnO2CCH2CO2SnClCy2Me]。化合物的体外抗肿瘤、杀菌和杀螨活性测试结果表明,部分化合物具有很好的生物活性。[HNR3][(Ph3Sn)3(O2CCH2CO2)2]·CH3CH2OH和[HNR3] [MeCy2ClSnO2CCH2CO2SnClCy2Me]配合物对人肺癌细胞株A-549、结肠癌细胞株HCT-8和肝癌细胞株Bel-7402的抑制率约为90%,[HNR3][MeCy2ClSnO2CCH2CO2SnClCy2Me]配合物对小麦赤霉、番茄早疫、芦笋茎枯、苹果轮纹、花生褐斑的杀死率都为100%,配合物[HNR3] [MeCy2ClSnO2CCH2CO2SnClCy2Me]的杀螨活性致死率大于90%。  相似文献   

14.
继过去20多年过渡金属原子簇化学的飞速发展,大量含μ_2-S桥的双核或多核过渡金属簇合物相继被合成出来.虽然对含弱端基配体桥硫簇合物的电子结构和成键特征用各种量子化学方法进行了较为广泛的研究,但对含强端基配体桥硫异金属簇合物的电子结构方面的研究尚少.为系统地总结桥硫簇合物的成键规律,本文用MAD—SCC—EHMO法计算了6个端基配体为NO或CO的异金属桥硫簇合物的电子结构,并系统地分析其成键特征。  相似文献   

15.
全氟烷基碘的加成反应一直活跃在氟化学中,即使近来也依然受到注意,这是因为由它们出发可做许多有用的中间体,其中氟烷基取代的醇可做织物表面处理剂,氟烷基取代的环氧化合物可做润滑剂。我们曾用引发剂,使ψ—碘代全氟烷基磺酰氟与多键类化合物在较温和条件下进行加成。黄维垣教授等用NaHCO_3—K_3[Fe(CN)_6]引发Cl(CF_2)_(4.6)I与烯丙醇顺利加成。  相似文献   

16.
Reaction of [RhCl(PPh3)2]2 with parahydrogen revealed that the binuclear dihydride [Rh(H)2(PPh3)2mu-Cl)2Rh(PPh3)2] and the tetrahydride complex [Rh(H)2(PPh3)2(mu-Cl)]2 are readily formed. While magnetisation transfer from free H2 into both the hydride resonances of the tetrahydride and [Rh(H)2Cl(PPh3)3] is observable, neither transfer into [Rh(H)2(PPh3)2(mu-Cl)2Rh(PPh3)2] nor transfer between the two binuclear complexes is seen. Consequently [Rh(H)2(PPh3)2(mu-Cl)]2 and [Rh(H)2(PPh3)2(mu-Cl)2Rh(PPh3)2] are not connected on the NMR timescale by simple elimination or addition of H2. The rapid exchange of free H2 into the tetrahydride proceeds via reversible halide bridge rupture and the formation of [Rh(H)2(PPh3)2(mu-Cl)RhCl(H)2(PPh3)2]. When these reactions are examined in CD2Cl2, the formation of the solvent complex [Rh(H)2(PPh3)2(mu-Cl)2Rh(CD2Cl2)(PPh3)] and the deactivation products [Rh(Cl)(H)PPh3)2(mu-Cl)(mu-H)Rh(Cl)(H)PPh3)2] and [Rh(Cl)(H)(CD2Cl2)(PPh3)(mu-Cl)(mu-H)Rh(Cl)(H)PPh3)2] is indicated. In the presence of an alkene and parahydrogen, signals corresponding to binuclear complexes of the type [Rh(H)2(PPh3)2(mu-Cl)(2)(Rh)(PPh3)(alkene)] are detected. These complexes undergo intramolecular hydride interchange in a process that is independent of the concentration of styrene and catalyst and involves halide bridge rupture, followed by rotation about the remaining Rh-Cl bridge, and bridge re-establishment. This process is facilitated by electron rich alkenes. Magnetisation transfer from the hydride ligands of these complexes into the alkyl group of the hydrogenation product is also observed. Hydrogenation is proposed to proceed via binuclear complex fragmentation and trapping of the resultant intermediate [RhCl(H)2PPh3)2] by the alkene. Studies on a number of other binuclear dihydride complexes including [(H)(Cl)Rh(PMe3)2(mu-H)(mu-Cl)Rh(CO)(PMe3)], [(H)2Rh(PMe3)2(mu-Cl)2Rh(CO)(PMe3)] and [HRh(PMe3)2(mu-H)(mu-Cl)2Rh(CO)(PMe3)] reveal that such species are able to play a similar role in hydrogenation catalysis. When the analogous iodide complexes [RhIPPh3)2]2 and [RhI(PPh3)3] are examined, [Rh(H)2(PPh3)2(mu-I)2Rh(PPh3)2], [Rh(H)2(PPh3)2(mu-I)]2 and [Rh(H)2I(PPh3)3] are observed in addition to the corresponding binuclear alkene-dihydride products. The higher initial activity of these precursors is offset by the formation of the trirhodium phosphide bridged deactivation product, [[(H)(PPh3)Rh(mu-H)(mu-I)(mu-PPh2)Rh(H)(PPh3)](mu-I)2Rh(H)2PPh3)2]  相似文献   

17.
含有亚硫酸四氟乙二醇酯(1)的四氟乙烷磺内酯(2)与H(CF_2)_4CH_2OH和三乙胺反应可获得草酸酯(CO_2CH_2CF_2CF_2—CF_2CF_2H)_2(3)。化合物(3)生成的机理解释为由于1的破环,生成了SOF_2和(COF)_2,后者进一步与H(CF_2)_4CH_2OH反应生成3。 3与二乙胺反应生成Et_2NCOCO_2CH_2(CF_2)_4H(4)。3和4皆为新化合物。  相似文献   

18.
刘旭锋  肖勋文  刘幸海 《结构化学》2011,30(10):1437-1441
Reaction of [(μ-SCH2)2NPh]Fe2(CO)6 with Ph2PCH2PPh2 in the presence of Me3NO·2H2O gave the title complex [(μ-SCH2)2NPh]Fe2(CO)5(Ph2PCH2PPh2)(1)in 78% yield.The new complex 1 was characterized by elemental analysis,spectroscopy and X-ray crys-tallography.It crystallizes in triclinic,space group P1 with a = 10.832(2),b = 12.003(2),c = 15.579(3),V = 1785.6(6)3,Z = 2,C32H26Fe2NO5PS2,Mr = 819.40,Dc = 1.524 g/cm3,μ(MoKα)= 1.064 mm-1,F(000)= 840,T = 113(2)K,the final R = 0.0543 and wR = 0.1218 for 6203 observed reflections(I > 2σ(I)).The Ph2PCH2PPh2 ligand resides in an axial position of the square-pyramidal coordination sphere of the Fe atom and trans to the benzene ring in order to reduce the steric repulsion between Ph2PCH2PPh2 and the benzene ring.  相似文献   

19.
胡昌明  陆亨尧 《化学学报》1987,45(2):201-203
研究了以CFCl2CF2CF=CF2(1)和CFCl2CF=CFCF2(2)为原料与三氯化铝的反应.结果获得重排产品CCl2=CF2CF2CF3(3).结果支持了从1到3的分子间重排反应的机理.在激烈条件下,3进一步与氯化铝反应得到CCl2=CFCCl2CF3(4),CCl2=CClCCl2CF3(5),CCl2=CClCCl2CClF(6),CCl2=CClCCl2CFCCl2(7)和CCl2=CClCCl2CCl3(8).由分离所得产品的结构可推断化合物3中氟原子被氯原子取代的稳定性按以下次序:CF3->CF=>=-CF2CF=.反应条件对产品得率的影响也被讨论了.  相似文献   

20.
在超声分子束条件下,由423、420、412.2和408.4nm的电离激光使OCS分子通过[3+1]共振增强多光子电离(REMPI)制备出OCS+(X2Π)离子后,在260-325nm范围内扫描解离激光获得了OCS+离子经由A2Π3/2←X2Π3/2(000)和A2Π1/2←X2Π1/2(000,001)跃迁的分质量光解离谱(母体离子OCS+的凹陷谱和碎片离子S+的增强谱).其中A2Π1/2←X2Π1/2(001)跃迁的光解离谱是首次观察到.由A2Π3/2←X2Π3/2(000)光解离谱得到了A2Π3/2电子态的光谱常数T0=31411.3cm-1,ν1=814.3cm-1;由A2Π1/2←X2Π1/2(000)光解离谱得到了A2Π1/2电子态的光谱常数ν1=816cm-1,ν2=(380.4±2.8)cm-1,ν3=(2052.7±5.1)cm-1,而从A2Π1/2←X2Π1/2(001)光解离谱拟合出的A2Π1/2电子态的ν1(786.4cm-1)稍有不同,表明在A2Π1/2←X2Π1/2(001)跃迁中X2П1/2电子态的C-O键振动(ν3)激发影响了A2Π1/2电子态C-S键的振动(ν1).实验结果表明:在A2Π1/2←X2Π1/2(000,001)跃迁的光解离谱中能够显著观察到属于A2Π电子态的ν2弯曲振动模激发的谱峰,例如A2Π1/2(020,120,021,…),而在A2П3/2(υ1υ2υ3)←X2Π3/2(000)跃迁的光解离谱中几乎没有观察到属于ν2弯曲振动模激发的谱峰.这种弯曲振动激发和A2П电子态的旋轨分裂分量(Ω)的相关性可以通过A2Π电子态的Fermi共振和Renner-Teller效应来解释.  相似文献   

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