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The interaction of the Negishi reagent Cp2ZrBun 2 with 1,4-bis(tert-butyl)butadiyne ButC≡C-C≡CBut leads to four products: a five-membered zirconacyclocumulene complex Cp2Zr(η4-ButC4But) (2) synthesized earlier by another method, the previously unknown seven-membered zirconacyclocumulene Cp2Zr[η4-ButC4(But)-C(C2But)=CBut] (3) as well as small amounts of the zirconocene binuclear butatrienyl complex Cp2(Bun)Zr(ButC4But)Zr(Bun)Cp2 (4), and the dimeric acetylide [Cp2ZrC≡CBut]2 (5). The structure of complexes 2–5 was established by X-ray diffraction studies.  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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Copolycarbonates of Bisphenol-A (BPA) and 1,4-bis(hydroxymethyl)cyclohexane have been prepared. The resulting copolymers have slightly lower glass-transition temperatures than BPA polycarbonate homopolymers. Crystallisation and annealing effects are also reduced. The results are generally similar to those obtained with copolymers of BPA and 1,4-bis(hydroxymethyl)decafluorobicyclo(2,2,1)-heptane [1] but the differences are less marked.  相似文献   

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Conclusions 1,2-Bis(B-amino-o-carboranyl)ethane and 1,4-bis(B-amino-o-carboranyl)benzene were synthesized.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1669–1670, July, 1976.  相似文献   

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Novel aromatic polyimides containing symmetric, bulky di-tert-butyl substituents unit were synthesized from 1,4-bis(4-aminophenoxy)2,5-di-tert-butylbenzene (BADTB) and various aromatic tetracarboxylic dianhydrides by the conventional two-stage procedure that included ring-opening polyaddition in a polar solvent such as N,N-dimethylacetamide to give poly(amic acid)s, followed by cyclodehydration to polyimides. The diamine was prepared through the nucleophilic displacement of 2,5-di-tert-butylhydroquinone with p-chloronitrobenzene in the presence of K2CO3, followed by catalytic reduction. Depending on the dianhydrides used, the poly(amic acid)s obtained had inherent viscosities of 0.83–1.88 dL g−1. Most of the polyimides formed transparent, flexible, and tough films. Tensile strength and elongation at break of the BADTB-based polyimide films ranged from 68–93 MPa and 7–11%, respectively. The polyimide derived from 4,4′-hexafluoro-isopropylidenebisphathalic anhydride had better solubility than the other polyimides. These polyimides had glass transition temperatures between 242–298°C and 10% mass loss temperatures were recorded in the range of 481–520°C in nitrogen. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1527–1534, 1997  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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Two novel coordination polymers with 3D metal-organic frameworks (MOFs) have been synthesized by reacting 1,4-bis(3-pyridyl)-2,3-diazo-1,3-butadiene (L) with zinc dichloride. Both compounds have the same repeating unit consisting of a distorted tetrahedral Zn(II) center coordinated by two chlorides and two pyridyl nitrogen atoms of two bridging bismonodentate L ligands, however, different structural conformations have been found, one forming a helical chain and the other producing a square-wave chain. The intermolecular C-H...Cl hydrogen bonds in 1 and 2 play important roles in the formation of three-dimensional coordination polymers. Compound 1 crystallized in an orthorhombic space group Pna21 with a = 7.9652(3), b = 21.4716(7), c = 8.2491(3)A, V = 1410.81(9) A 3 and Z = 4. Compound 2 crystallized in a monoclinic space group P21/n with a = 9.1752(3), b = 14.5976(4), c = 10.3666(3) A , beta = 98.231(2) degrees , V = 1374.16(7) A 3 and Z = 4.  相似文献   

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Zhan SZ  Li D  Zhou XP  Zhou XH 《Inorganic chemistry》2006,45(23):9163-9165
Two unprecedented 3D polyknotted isomers, arisen from different linkage modes of SCN-, were obtained from 3,5-bis(4-pyridyl)-1H-pyrazole (Hbppz) and CuSCN under different conditions.  相似文献   

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1,4-Bis(2,5-dimethyl-4-hydroxypiperidino)-2-butene and 1,4-bis(2,5-dimethyl-4-hydroxypiperidino)-2-butyne (II and III) were obtained by the action of 1,4-dibromo-2-butene and 1,4-dibromo-2-butyne on the form of 2,5-dimethyl-4-piperidol (I). The benzoates (IV and V) were obtained by acylation of II and III with benzoyl chloride.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 352–353, March, 1971.  相似文献   

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1,4‐Bis(4‐alkylpyridinium)butadiyne triflate ( 2a and 2b ) that was prepared by the reaction of 1,4‐bis(4‐pyridyl)butadiyne ( 1 ) with alkyl trifluoro‐methanesulfonate, was found to grow into a large crystal as a result of the quaternized structure. The thermal treatment of 2a and 2b gave rise to 1,4‐addition polymerization to yield the polydiacetylene. The third‐order nonlinear optical susceptibility [χ(3)] of the polymer was determined by the femto‐second Z‐scan method to exhibit the remarkable high value of 1.1 × 10?11 esu at 650 nm. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3686–3691, 2001  相似文献   

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The hydrothermal reaction between Cd(NO(3))(2), trimesic acid (H(3)BTC), 1,2-bis(4-pyridyl)ethane (BPE), and triethylamine under mild conditions yielded, after 3 days, a novel three-dimensional metal-organic framework, [Cd(1.5)(BTC)(BPE)(H(2)O)(2)].(H(2)O), which has been characterized structurally using single-crystal and powder X-ray diffraction, elemental analysis, infrared and Raman spectroscopies, thermogravimetry, and differential scanning calorimetry. The structure exhibits a 2-fold interpenetration of identical [Cd(1.5)(BTC)(BPE)(H(2)O)(2)] single frameworks, described as an unusual (9) net. Crystal data: Cd(1.5)C(21)H(21)N(2)O(9), monoclinic, space group C2/c, with a = 10.8264(5) A, b = 17.4563(5) A, c = 24.2605(11) A, beta = 91.978(2) degrees, V = 4582.2(3) A(3), and Z = 8.  相似文献   

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Isomeric 1,3- and 1,4-bis[3(4)-nitrofuroxan-4(3)-yl]nitro(dinitro)benzenes were synthe-sized in high yields by nitration of the corresponding 1,3- and 1,4-bis[3(4)-nitrofuroxan-4(3)-yl]benzenes with a mixture of 100% nitric acid and concentrated sulfuric acid. The influence of 3- and 4-nitrofuroxanyl fragments on the regioselectivity of the nitration was revealed. The structure of 1,3-bis(4-nitrofuroxan-3-yl)-4-nitrobenzene was confirmed by X-ray diffraction analysis. 1,3- and 1,4-Bis(3-nitrofuroxan-4-yl)nitrobenzenes underwent thermal isomerization to more thermodynamically favorable 1,3- and 1,4-bis(4-nitrofuroxan-3-yl)nitrobenzenes.  相似文献   

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Two novel ruthenium polypyridine complexes, [Ru(bpy)(2)Cl(BPEB)](PF(6)) and ([Ru(bpy)(2)Cl](2)(BPEB))(PF(6))(2) (BPEB = trans-1,4-bis[2-(4-pyridyl)ethenyl]benzene), were synthesized and their characterization carried out by means of elemental analysis, UV-visible spectroscopy, positive ion electrospray (ESI-MS), and tandem mass (ESI-MS/MS) spectrometry, as well as by NMR spectroscopy and cyclic voltammetry. Cyclic and differential pulse voltammetry for the mononuclear complex showed three set of waves around 1.2 V (Ru(2+/3+)), -1.0 V (BPEB(0/)(-)), and -1.15 (BPEB(-/2-)). This complex exhibited aggregation phenomena in aqueous solution, involving pi-pi stacking of the planar, hydrophobic BPEB ligands. According to NMR measurements and variable-temperature experiments, the addition of beta-cyclodextrin (betaCD) to [Ru(bpy)(2)Cl(BPEB)](+) leads to an inclusion complex, breaking down the aggregated array.  相似文献   

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