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Polymers [N(PN)4(C6H5)6N?P(C6H5)2(CH2)4P(C6H5)2]x and [N(PN)4(C6H5)6N?P–(C6H5)2C6H4C6H4P(C6H5)2]x have been formed by thermal copolymerization of trans-2,6-diazidohexaphenylcyclophosphonitrile [N3(PN)4(C6H5)6N3] with either 1,4-bis-(diphenylphosphino)butane [(C6H5)2P(CH2)4P(C6H5)2] or 4,4′-bis(diphenylphosphino)-biphenyl [(C6H5)2C6H4C6H4P(C6H5)2]. The maximum molecular weights obtained were about 10,000. A polymer endcapped with triphenyl phosphine was stable to 400°C.  相似文献   

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陈煦  周秀中 《化学学报》1984,42(5):479-486
利用HCl-AlCl_3对硅—苯键的断裂反应合成了1,4-双(烷基氯硅基)丁烷和1-(二甲基氯硅基)-4-(甲基二氯硅基)丁烷,研究了它们与水、氨(胺)、硫化氢及活泼金属(Li,K-Na,Mg)的反应。通过这些反应合成了十一个在环系中含有Si—A—Si(A=O,NR,S)链节的七员杂环化合物和两个在环系中含有Si—Si(或Si—Si—Si)键的六员(或七员)杂环化合物。  相似文献   

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The epoxidation of 1,4-bis(allyloxy)butane (DiBan) with hydrogen peroxide as an oxidant in the presence of o-phosphoric acid and sodium tungstate as an epoxidation catalyst was carried out in an organic solvent/aqueous solution two-phase medium. A few different phase-transfer catalysts were used in the process. The effect of the stirring speed, nature of solvent, the type of PT catalyst and molar ratio of H(2)O(2):DiBan, DiBan:Na(2)WO(4):H(3)PO(4) on the DiBan conversion as the function of time was studied. Based on the experimental results, a pseudo-first-order expression for the reaction rate was applied and most efficient conditions epoxidation were developed.  相似文献   

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The structure of [Cd(Btb)2Br2] (I) (Btb = 1,4-bis(triazol-1-yl)butane) exhibits a two-dimensional (4,4) network through Btb-bridge in which the Cd(II) atom is in a distorted octahedral environment formed by four nitrogen atoms of the triazoles and two trans-Br atoms. The crystals are monoclinic, space group P21/n with a = 7.6778(6), b = 18.2237(8), c = 8.7655(5) Å, β = 113.4534(19)°. The Btb ligand demonstrates the completely anti conformation.  相似文献   

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The chlorometylation of linear and crosslinked polystyrene with 1,4-bis(chloromethoxy) butane was studied, and the behavior of 1,4-bis(chloromethoxy)butane in the presence of chloromethylation catalysts was also established by 1H-NMR spectroscopy.  相似文献   

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A kinetic study of the oxidative addition of RC6H4CN (R = H, m-CN, p-CN) to Ni(DEPB)2 (DEPB = 1,4-bis(diethylphosphino)butane) suggests a template mechanism leading to the fission of one C---CN bond. The reaction products are trans-planar cyano-organonickel(II) complexes, Ni2(μ-DEPB)2(RC6H4)2(CN)2 and Ni(η1- DEPB)(RC6H4)(CN), in equilibrium. through exchange of DEPB.  相似文献   

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以1,4-双(二苯基膦)丁烷为交联剂,以具有四甲基联苯结构的聚芳醚酮为基体材料,分别制备了刚性三苯基膦和柔性三丁基膦修饰的阴离子交联膜材料.交联剂在交联结构形成的过程中转变成季膦盐,在提高膜材料机械稳定性的同时保持离子交换功能基团的含量.研究了2种阴离子交换膜的尺寸稳定性、电导率、机械性能及耐碱稳定性等.研究结果表明,当交联度为20%时,三苯基膦与三丁基膦修饰的阴离子交换膜的拉伸强度分别由未交联时的27和18 MPa提高到45和30 MPa;交联的膜材料在60℃的3 mol/L KOH溶液中浸泡120 h后,三苯基膦修饰的阴离子交换膜的电导率保留率为81%,三丁基膦修饰的阴离子交换膜的电导率保留率为69%,膜的耐碱稳定性均较未交联时有明显提高.交联度相同时,三苯基膦修饰的阴离子交换膜表现出更高的拉伸强度和更好的耐碱稳定性.  相似文献   

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High molecular weight aliphatic poly(carbonate-sulfone) homopolymer (PC-343) and random copolymer (PC-343-10) were synthesized from 1,4-bis(3-hydroxypropylsulfonyl)butane (Diol-343) and a 1/1 molar mixture of Diol-343 and 1,10-decanediol, respectively. As a comparison, an aliphatic polycarbonate homopolymer (PC-10) was prepared from 1,10-decanediol. While PC-10 exhibited a single melting peak during its DSC heating scan, both PC-343 and PC-343-10 exhibited multiple reproducible first-order transitions during DSC heating scans. Both PC-343 and PC-343-10 showed broad reflections in their WAXD diagrams; the crystalline order of PC-343 is higher than that of PC-343-10. Based on the DSC and WAXD results and our discovery on the liquid crystalline behavior of aliphatic poly(carbonate-sulfone)s from 1,3-bis(hydroxypropylsulfonyl)propane, we suggest PC-343 and PC-343-10 are liquid crystalline and the liquid crystalline phase formation is directed by the dipole–dipole interactions between sulfone groups. Films were obtained from these polymers by compression molding and dielectric analyses were conducted on them. One glass transition related dielectric relaxation was observed in PC-343-10. One glass transition related dielectric relaxation and one sub-glass transition related dielectric relaxation were observed in PC-343. The glass transition temperature increases with the increase of sulfone content in the polymers. A dramatic rise in dielectric constant with temperature was observed in PC-343 and PC-343-10 at low frequencies, which is probably due to the sulfone dipole interaction with the electrical field. © 1994 John Wiley & Sons, Inc.  相似文献   

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The synthesis and molecular structure of a new dinuclear copper(Ⅰ) complex [Cu(dppb)(NO 3)] 2 are reported.The compound crystallizes in the monoclinic system,space group P2 1 /n with a=12.830(3),b=10.899(2),c=19.666 (4),β=104.69(3)°,V=2660.1(9)3,Z=4,D c=1.378 g/cm 3,F(000)=1144,the final R=0.0600 and wR=0.0668 for 2951 observed reflections with I > 2σ(Ⅰ).The complex contains a folded Cu 2 P 4 core structure,with two Cu(Ⅰ) atoms being bridged by a pair of dppb ligands to form a 14-membered Cu 2 P 4 C 8 zigzag ring.The ligand sphere of each metal center is completed by a nitrate anion in a chelating fashion.  相似文献   

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X-ray structures have been determined for the olefin-containing complexes RuCl3(BDPH) and RuCl2(CO)(BDPH); BDPH = 1,6-bis(diphenylphosphino)-trans-hex-3-ene. Both compounds crystallise in space group Pbca with eight molecules in unit cells of dimensions RhCl3(BDPH) a 16.109(8), b 20.359(12), c 17.194(4) Å; RuCl2(CO)(BDPH) a 16.279(1), b 20.160(1), c 17.334(1) Å. Least-squares refinement returned residuals, R, of 0.030 and 0.067 respectively. In the ruthenium complex the CO and one Cl ligand are statistically interchanged. Both complexes are characterised by weak metal—olefin bonding and a twisted olefin orientation. The geometries are compared with those in other IrI and IrIII complexes containing the BDPH ligand.  相似文献   

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By adopting “grafting from” manner, polystyrene was grafted onto the surface of silica gel particles with an average size of 125 μm in a solution polymerization system, and grafted particle PSt/SiO2 was prepared. Using 1,4-bis (chloromethoxy) butane (BCMB, it is nontoxic.) as chloromethylation reagent, chloromethylation reaction for the grafted particle PSt/SiO2 was performed in the presence of Lewis acid catalyst SnCl4. At the same time, cross-linked styrene-divinylbenzene copolymer (CPS) microsphere also was chloromethylated with the same reagent as PSt/SiO2, so that two kinds of chloromethylated polystyrene particles were obtained, and they are chloromethylated grafted particle (CMPS/SiO2) and chloromethylated cross-linked polystyrene (CMCPS) microsphere, respectively. The chemical structures and compositions of the two particles were characterized using Fourier transform infrared and Volhard method. The effects of various factors on the chloromethylation reactions were mainly investigated. The experimental results show that the process to prepare the two kinds of chloromethylated polystyrene particles not only has the character of environment friendness and low cost but also is convenient to control via adjusting various reaction conditions. The main reaction conditions affecting the chloromethylation reactions are reaction time, the added amount of BCMB, and the used amount of solvent and catalyst. They influence the reaction in two respects: (1) the chloromethylation degrees of polystyrene are different under different conditions; (2) Friedel–Crafts cross-linking reaction between polystyrene macromolecules is accelerated or inhibited under different conditions (for CPS microsphere, this cross-linking reaction also is called the additional cross-linking). Under suitable conditions, the two kinds of chloromethylated polystyrene particles with a high chlorine content (about 17%, this chlorine content was calculated based on polystyrene weight) can be gained using SnCl4 as catalyst and CH2Cl2 as solvent at room temperature for 10 h and basically without cross-linking or additional cross-linking.  相似文献   

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1,4-Bis(chloromethyl)-and 1,4-bis(bromomethyl)cubanes were synthesized by the reactions of triphenylphosphine with CCl4 and NBS, respectively. The structures of the compounds were studied by X-ray diffraction analysis. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1399–1401, August, 2006.  相似文献   

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The isolation and the X-ray crystal structure of physiological copper(II)-L-histidine complex are reported. The neutral five-coordinate complex shows distorted square pyramidal geometry with bidentate and tridentate L-histidine ligands. The basic character of the pendent imidazole group and H-bonding interactions of bidentate L-histidine ligand are important for copper transport. The unique structural features help explain the origin of its thermodynamic stability and kinetic reactivity in human blood along with the ternary copper(II)-amino acid complexes. The role of L-histidine in interaction with copper(II)-albumin, in cellular uptake of copper, and in treatment of Menkes disease can be studied using these results.  相似文献   

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The structure of [Co(Btb)2Cl2] (Btb = 1,4-bis(1,2,4-triazol-1-yl)butane) demonstrates a two-dimensional (4,4) network through the Btb bridge in which the Co(II) atom is in a distorted octahedral environment formed by four nitrogen atoms of the triazoles and two trans-Cl? ions. The crystals are monoclinic, space group P21/c with a = 7.3143(3), b = 18.5703(7), c = 8.8713(4) Å, β= 117.0633(10)°.  相似文献   

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