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1.
具有五元环结构的偶氮化合物4,4-二甲基-4,5-二氢-3H-吡咯(N2C5H10),与Fe3(CO)12在甲苯中加热回流反应,生成双铁六羰基配合物Fe2(N2C5H10)(CO)6(1).反应中N=N双键被还原,配体以(N2C5H102-的形式与FeIFeI配位,形成具有蝶形结构的34e-化合物.研究了在脱羰基试剂Me3NO存在条件下,1和单齿膦配体PR3反应生成Fe2(N2C5H10)-(CO)5(PR3)(PR3=PPh3,2a;PCy3,2b)单取代配合物.光照条件下,化合物1中的CO配体还可以被双齿膦配体dppe[dppe=1,2-C2H4(PPh22]和dppbz[dppbz=1,2-C6H4(PPh22]取代,生成产物的类型和膦配体的夹角相关.与夹角较大的dppe反应,生成桥连产物Fe2(N2C5H10)(CO)4μ-dppe)(3a);而与刚性较大的dppbz反应时,Fe2(NR)2的蝶形结构打开呈四元环;其中一个Fe上的CO被取代,dppbz与该Fe中心螯合,生成具有桥连CO的化合物Fe2(N2C5H10)(μ-CO)(CO)4κ2-dppbz)(3b).合成具有FeI-CO-FeI结构的羰基化合物,一直是模拟[FeFe]氢化酶活性中心还原态结构Fe2(SR)2μ-CO)-(CO)5-xLx的重要挑战.该类Fe2(NR)2(CO)6-x(PR3x化合物的合成,能为探索模拟[FeFe]氢化酶活性中心结构提供新的途径和思路.以上化合物均通过核磁[31P(1H)NMR]、红外光谱(IR)、元素分析及X射线单晶结构衍射等表征.  相似文献   

2.
本文用13C NMR法系统研究了溶液中顺式二氯二氨合铂与胸苷、胞苷、鸟苷和5'-腺嘌呤单核苷酸的作用,确定了不同条件下形成配合物的组成及其分子申铂原子与配体的成键方式。在中性介质中顺铂分别与胸苷、胞苷作用,生成N3配位的顺-[Pt(NH3)2(ThyH-1)2]和顺-[Pt(NH3)2(Cyt)2]2+;与鸟苷随摩尔比不同相应生成顺-[Pt(NH3)2(N2-Guo)2]2+和[Pt(NH3)2(N2,N1-GuoH-1)]nn+,当pH=3和摩尔比为1时,尚有微量[Pt(NH3)2(N7,O(C6)Guo)]2+生成;在中性介质中顺铂与5'-AMP亦随摩尔比不同,生成顺-[Pt(NH3)2(N7-5'-AMP)2]2-或兼生成顺-[Pt(NH3)2(N7,N1-5'-AMP)]n。根据所得结果讨论了顺铂抗癌作用机制,提出了顺铂可能与DNA同一链上相邻二个鸟嘌呤基上的N7N1键合形成链内交联的新机制。  相似文献   

3.
分子磁体的设计与合成一直是当今物理和化学的热门研究课题. 受分子磁体启发, 通过引入叠氮磁耦合基团以及长链棒状配体4,4'-二咪唑联苯(L), 我们构筑了三个磁性化合物[Co2(N3)4(L)2.5](1), [Ni2(N3)3(NO3)(L)2.5](2)和[Mn2(N3)4(L)2.5](3). 结构分析显示, 这是三个同构化合物, 展现了一种基于线性叠氮四核单元的二维层网络. 有意义的是, 这种线性叠氮四核单元还未曾被人报道. 磁性研究表明, 三个化合物都是铁磁耦合, 这是由于EO-叠氮所导致的. 通过拟合实验数据, 我们得到了三个化合物的磁耦合常数, 进一步验证了上面磁构相关性的讨论.  相似文献   

4.
Thiolate-bridged hetero-bimetallic complexes [Cp*M(Me CN)N2S2Fe Cl][PF6](2, M = Ru; 3, M = Co, Cp*= η5-C5Me5, N2S2= N,N’-dimethyl-3,6-diazanonane-1,8-dithiolate) were prepared by self-assembly of dimer [N2S2Fe]2 with mononuclear precursor [Cp*Ru(MeCN)3][PF6] or [Cp*Co(Me CN)3][PF6]2 in the presence of CHCl3 as a...  相似文献   

5.
凡一明  程骏  高亚飞  施敏  邓亮 《化学学报》2018,76(6):445-452
研究了氮上取代基为1-金刚烷基的苯基硼桥联三氮杂环卡宾配体在铁促进的氮气活化转化反应中的应用.通过苯基硼桥联三氮杂环卡宾亚铁氯化物[PhB(AdIm)3FeCl](1)在氮气氛下与KC8反应合成了一价铁分子氮配合物[PhB(AdIm)3Fe(N2)](2).进一步通过2与KC8和18-C-6的反应合成了零价铁分子氮配合物[K(18-C-6)(THF)]-[PhB(AdIm)3Fe(N2)](4).这些配合物均通过核磁共振、紫外吸收光谱、红外光谱、元素分析等表征,其中配合物2和4的结构经单晶X射线衍射表征确定.配合物2和4的N-N伸缩振动频率分别为1928和1807 cm-1,均为同价态铁末端分子氮配合物最低值.在过量KC8和Me3SiCl存在下,配合物1,2和4均可催化N2的还原硅基化反应,生成N(SiMe33.催化体系的TON可达87.  相似文献   

6.
对LiNd(PO3)4晶体分别在N2气和空气下进行了TG和DTA热分析研究,给出TG和DTA曲线,讨论了LNP晶体在N2气和空气下不同的热分解机理.得到分解产物分别为Nd4(P2O7)3和NdP2O7.  相似文献   

7.
张俊峰  甘欣  傅文甫 《化学学报》2007,65(11):1071-1075
通过亲核取代反应, 在2,2'-联苯二酚氧基环氯磷腈母体N3P3(O2C12H8)2Cl2 (1)和N3P3(O2C12H8)Cl4 (2)上引入2-醛基吡啶与对胺基苯酚形成的席夫碱侧基, 合成了两种新型环磷腈化合物N3P3(O2C12H8)2(p-O-Ph-N=C-Py)2 (3)和N3P3(O2C12H8)(p-O-Ph-N=C-Py)4 (4), 这些化合物是一类能形成配合物的多齿配体. 通过元素分析, IR, 1H NMR, 31P NMR和TOFMS确定其结构, 研究了它们的吸收光谱和荧光光谱. H和Cu离子对其光谱性质的影响研究表明两种化合物的吸收和荧光光谱对H和Cu离子异常敏感, 因而在作为这些阳离子的荧光探针方面具有应用前景.  相似文献   

8.
A mild,efficient and eco-friendly process for the electrophilic nitration is described using N2O5 as a green nitrating agent in the presence of rare earth metal triflates[RE(OTf)3]under mild conditions.  相似文献   

9.
采用超声法一步合成了SiO2包覆金属-有机骨架[Zn6(OH)3(BTC)3(H2O)3] ·7H2O(Zn-MOF, BTC=1,3,5-均苯三羧酸根)纳米晶, 在N2保护下, 热解Zn-MOF@SiO2获得了ZnO/C/SNTs复合物, 进而与布洛芬(HIBU)反应合成药物组装体Zn(IBU)2/C/SNTs. 通过透射电子显微镜(TEM)、 傅里叶变换红外光谱仪(FTIR)、 高分辨透射电子显微镜(HRTEM)和X射线衍射仪(XRD)对样品的结构和形貌进行表征. 结果显示, Zn-MOF@SiO2呈棒状, 具有清晰的核/壳结构, 形貌单一, 分散性良好. 煅烧后SNTs结构稳定, 形貌基本不变. 载药实验表明, 药物组装体的载药量为752 mg/g, 并具有良好的pH响应性能.  相似文献   

10.
不同整比性VO2纳米粉体的合成   总被引:1,自引:0,他引:1  
以V2O5,HCl,N2H4·2HCl和NH4HCO3为原料合成了紫红色多晶(NH4)5[(VO)6(CO3)4(OH)9]·10H2O(I),产率80%~95%.在N2气流中对前体I进行了TG/DTG和DTA热分析.研究了前体I在N2-空气气流中热解时氧分压(po2)和反应温度对产物VO2整比性的影响.结果表明,在500℃条件下,VOx中的x值与po2呈正比关系,在po2=30.3Pa条件下,在450~520℃区间,产物为缺氧VO2;在t<450℃和t>520℃时,产物为富氧VO2.在合适的条件下,成功地合成了从VO1.927到VO2.080之间不同整比性的VO2粉体.产物组成均匀,其XRD谱未观察到非VO2的杂质峰.VO2粉体颗粒的平均粒径为20nm,粒度分布均匀并呈球形.  相似文献   

11.
A structural study of odd-numbered n-alkane (Cn) binary mixtures (C21 : C23) was carried out on powder samples using a Guinier-de Wolff camera with increasing concentration of n-C23 at 293 K.

Despite the reports in the literature, these molecular alloys do not form an orthorhombic continuous homogeneous solid solution to C21 from C23 at “low temperature”. Instead, as already observed in two even-numbered Cn systems, X-ray diffraction results show the existence of seven solid solutions as the molar concentration of C23 increases: four terminal solid solutions, denoted β0(C210(C23), isostructural with the “low temperature” phase of pure C21 and C23 (Pbcm), β′0(C21) and β′0(C23), identical to the phase β′0 which appears in pure C23 above the δ transition, and three orthorhombic intermediate solid solutions, designated β″1, β′1 and β″2.

On the basis of powder X-ray photographs, the phases β″1 and β″2 (C21 : C23) are indistinguishable, and they are isostructural with the intermediate solid solution β″ of the even-numbered Cn binary systems (C22 : C24) and (C24 : C26). The phase β′1(C21 : C23) is also isostructural with the two indistinguishable intermediate solid solutions β′1 and β′2 of the molecular alloys (C22 : C24) and (24 : C26).

From this study and our other laboratory results, the sequences of appearance of the solid solutions and the structural identities between these phases are established at “low temperature” for all the binary molecular alloys of consecutive Cn (odd-odd, even-even or odd-even: 19 < n < 27) when increasing the solute concentration.  相似文献   


12.
杯芳烃钕配合物均相体系催化丁二烯聚合   总被引:6,自引:0,他引:6  
应用新型配体杯芳烃钕配合物与三异丁基铝以及添加Al(i-Bu)2Cl为第三组分构成二元、三元均相催化体系催化丁二烯聚合.研究结果表明,对于杯[6,8]芳烃钕(C[n]NdxCly)/Al(i-Bu)3/汽油体系,当n(Al)/n(Nd)=40~100,50℃时具有中等催化聚合活性,所制得聚丁二烯的粘均分子量为1×105~2×105,顺-1,4结构含量为89%左右,添加适量Al(i-Bu)2Cl能提高催化活性.杯芳烃钕(C[n]Nd)构成的三元体系在n(Al)/n(Nd)=30,n(Cl)/n(Nd)=1~3时不同杯芳烃的活性次序为:C6>C4>C8  相似文献   

13.
Interaction between binary surfactant mixtures containing anionic surfactants viz. sodium dodecyl sulphates (NaDS) and magnesium dodecyl sulphates (Mg(DS)2) and a nonionic surfactants viz. dodecyl dodecapolyethylene glycol ether (C12E12) and dodecyl pentadecapolyethylene glycol ether (C12E15) in water at different mole fractions (0–1) were studied by surface tension, viscometry and dynamic light scattering (DLS) methods. The composition of mixed micelles and the interaction parameter, β evaluated from the CMC data obtained by surface tension for different systems using Rubingh's theory were discussed. Activity coefficient (f1 and f2) of metal dodecyl sulphates (MDS)/C12Em (m = 12, 15) mixed surfactant systems were evaluated, which shows extent of ideality of individual surfactant in mixed system. The estimated interaction parameter indicates an overall attractive interaction in the mixed micelles, which is predominant for NaDS as compared to Mg(DS)2. Counter ion valency has specific effect on the mixed micelles, as Mg(DS)2 has less interaction with nonionic surfactants in comparison to NaDS due to strong condensation of counter ion. The stability factors for mixed micelles were also discussed by Maeda's approach, which was justified on the basis of steric factor due to difference in head group of nonionic surfactant. DLS measurements and viscosity data reveals the synergism in mixed micelles, showing typical viscosity trends and linearity in sizes were observed.  相似文献   

14.
The coordinatively unsaturated uranium(IV) complex U[N(C6H5)2]4 has been prepared via the stoichiometric reaction of diphenylamine with [(Me3Si)2N]2 H2. U[N(C6H5)2]4 coordinates Lewis bases such as Et2O, THF, pyridine or (EtO)3PO, based on electronic absorption spectroscopy and 1H NMR studies. Exchange between U[N(C6H5)2]4 and U[N(C6H5)2]4(L), where L is THF or pyridine, is rapid on the NMR time-scale between 307 and 323 K. Measurement of equilibrium constants for L = THF provides ΔH and ΔS values of −60 kJ mol−1 and −1.8 × 102 J K−1 mol−1, respectively. U[N(C6H5)2]4 coordinates and binds (EtO)3PO much more tightly (Keq = & > 104 M−1) than THF or pyridine with the exchange rate between U[N(C6H5)2]4 and U[N(C6H5)2]4[OP(OEt)3] being close to the NMR time-scale.  相似文献   

15.
The synergic extraction of uranyl thiocyanate with binary system of 1-phenyl-3-methy1~4-benzoylpyrazolone-5 (PMBP)and tributyl phosphate(TBP)or tetraphenylarsonium chloride [(C6H5)4AsCl] and ternary system of PMBP-TBP-(C6H5 )4AsCl was studied.There was an obvious synergic effect of uranium (VI)from thiocyanate medium in binary and ternary systems.The formation of a ternary extracted complex,(C6H5)4AsUO2.(NCS)A2 TBP,was confirmed by the slope method.A method was first proposed for the calculation of the equilibrium constant of ternary synergic reaction.  相似文献   

16.
Three novel compounds, [Co(en)3]2[Zr2(C2O4)7]·2H20(HNU-2, en=ethylenediamine), [Co(NH3)6]· [Ce(CzO4)3(H2O)]·H2O(HNU-3) and [Co(dien)2][Gd(C2On)3]·0.75H2O(HNU-4, dien=dethylenetriamine) were hydro- thermal synthesized based on the templates of [Co(en)3]C13, [C0(NH3)6]C13 and [Co(dien)2]C13, respectively. The Zr4+ Ce3+ and Gd3+ cations are all coordinated by four oxalates to form [M(C2O4)n(H2O)n]m (M=Zr, Ce or Gd; n=0 or 1; m=4 or 5), which are similar to [In(C2O4)4]5- in NKB-1, and can be regarded as 4-connected building units. The [M(C2O4)a(H2O)n]m units are connected via sharing the bis-bidentate bridging oxalate ligands to form binuclears in HNU-2 and 1D "zigzag" chains in HNU-3 and HNU-4. cular building units to design 3D open frameworks with It is suggested that these compounds could be used as mole- zeolite topologies.  相似文献   

17.
A series of chromium(III) complexes [Cr(bipy)(HC2O4)2]Cl·3H2O (1), [Cr(phen)(HC2O4)2]Cl·3H2O (2), [Cr(phen)2(C2O4)]ClO4 (3), [Cr2(bipy)4(C2O4)](SO4)·(bipy)0.5·H2O (4) and [Mn(phen)2(H2O)2]2[Cr(phen)(C2O4)2]3ClO4·14H2O (5) were synthesized (bipy=4,4′-bipyridine, phen=1,10-phenanthroline), while the crystal structures of 1 and 3–5 have been determined by X-ray analysis. 1 and 3 are mononuclear complexes, 4 contains binuclear chromium(III) ions and 5 is a 3D supromolecule formed by complicated hydrogen bonding. 1–3 are potential molecular bricks of chromium(III) building blocks for synthesis heterometallic complexes. When we use these molecular bricks as ligands to react with other metal salts, unexpected complexes 4 and 5 are isolated in water solution. The synthesis conditions and reaction results are also discussed.  相似文献   

18.
A study has been carried out of the catalytic activity of the systems formed by [HRh{P(OPh)3}4] or [HRh(CO){P(OPh)3}3] with the modifying ligands P(OPh)3, PPh3, diphos and Cp2Zr(CH2PPh2)2 in hydroformylation of hex-1-ene (at p = 5 bar). The best results were obtained with the system [HRh{P(OPh)3}4]+Cp2Zr(CH2PPh2)2 (75–85% yeild of aldehydes).  相似文献   

19.
The biphasic hydroformylation reaction of oct-1-ene, has been investigated by using the water-soluble dinuclear complex [Rh2(μ-StBu)2(CO)2(TPPTS)2] as precursor. Addition of ethanol as a cosolvent dramatically improved the yields but the good regioselectivity in linear aldehyde observed for neat oct-1-ene—water systems (97%) decreased to 83% (for 22% ethanol w/w). It is shown that the dinuclear framework cannot be maintained, that the mononuclear complex [RhH(CO)(TPPTS)3] is formed, and that thiol and significant amounts of [Rh2(μ-StBu)2(CO)4] move into the organic phase. This reaction from the dinuclear species requires the simultaneous presence of water and carbon monoxide. Introduction of the water-soluble thiol HS(CH2)3NMe2 in the bridging positions affords the complex [Rh2(μ-S(CH 2)3NHMe2)2(CO)2(TPPTS)2]Cl2 which can be kept in the aqueous hase but has a low level of catalytic activity.  相似文献   

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