共查询到20条相似文献,搜索用时 15 毫秒
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E. N. Rasadkina P. V. Slitikov A. I. Stash E. E. Nifant’ev 《Russian Chemical Bulletin》2005,54(2):449-451
1,4-Bis(hydroxymethyl)benzene undergoes bisphosphorylation with P(NEt2)3 at room temperature. The reaction produces no cyclic structures.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 440–442, February, 2005. 相似文献
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Yuvraj Singh Negi Yoshi-Ichi Suzuki Ichiro Kawamura Masa-Aki Kakimoto Yoshio Imai 《Journal of polymer science. Part A, Polymer chemistry》1996,34(9):1663-1668
Aromatic soluble polyamides and copolyamides having hexafluoroisopropylidene and isopropylidene moieties in the molecular structure of polymer chain were prepared by reacting the aromatic diacid chlorides and fluorine or nonfluorine containing aromatic diamines using low-temperature polycondensation process. Polymers were produced with high yield and moderate to high inherent viscosity. All polyimides and copolyamides showed thermal stability above 440°C and glass transition temperature above 200°C. Some of the polyamides were cast into transparent bulk films which were further characterized by mechanical, x-ray, and water absorption analysis. Fluoro polyamides showed superior structural properties as compared to nonfluoro polyamides. © 1996 John Wiley & Sons, Inc. 相似文献
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Shinji Watanabe Hitoshi Murayama Miki Murata Yuzuru Masuda Masaru Tanabe Yoshio Imai 《Journal of polymer science. Part A, Polymer chemistry》1998,36(13):2229-2235
New polyarylates having benzopinacolone units were synthesized from 2,2-bis(4-hydroxyphenyl)-1,2-diphenylethanone and aromatic dicarboxylic acid chlorides. The polymers having an inherent viscosity of 0.71–0.94 dL/g were obtained by the two-phase method using toluene as an organic solvent. The polymers were easily soluble in various organic solvents and had high glass transition temperatures in the range of 200–240°C. An aromatic polyether having benzopinacolone unit was also prepared. However, its inherent viscosity was low because of the occurrence of a side reaction. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2229–2235, 1998 相似文献
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Yasuo Saegusa Minoru Kuriki Akihiro Kawai Shigeo Nakamura 《Journal of polymer science. Part A, Polymer chemistry》1994,32(1):57-63
A series of fluorine-containing aromatic homopolyformal and copolyformals with a wide range of unit ratio were synthesized by the solution polycondensation of 2,2-bis (4-hydroxyphenyl)-1,1,1,3,3,3-hexafluoropropane (Bisphenol AF) and/or 2,2-bis (4-hydroxyphenyl)propane (Bisphenol A) with dichloromethane, and the effect of the fluorine substitution on the preparation and properties of these polymers was investigated by comparing with those of Bisphenol-A-based homopolyformal without fluorine. Irrespective of the ratio of Bisphenol AF, high-molecular-weight, fluorine-containing polyformals with reduced viscosities of 1.4–5.3 dL/g were obtained in high yields by using dichloromethane as both comonomer and solvent, potassium hydroxide as a base, and N-methyl-2-pyrrolidone as a comedium at 75°C for 4 h. Their solubility increased markedly by the introduction of fluorine atom. Colorless, transparent, and tough films were cast from chloroform solution irrespective of fluorine content. These films had good mechanical properties comparable to that of Bisphenol-A-based homopolyformal. The contact angles by water were larger than 90°, regardless of their fluorine contents, at 25°C. The glass transition temperature and thermal stability increased monotonically with increasing fluorine content. © 1994 John Wiley & Sons, Inc. 相似文献
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Conclusions Geminal bis(difluoroamino) alcohols were obtained by reacting difluoroamine with the trifluoroacetates of acetylenic alcohols and subsequent saponification. Some of the chemical properties of 2,2-bis(difluoroamino)-propanol were studied.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 458–460, February, 1982. 相似文献
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Mi Hie Yi Wenxi Huang Bum Jin Lee Kil-Yeong Choi 《Journal of polymer science. Part A, Polymer chemistry》1999,37(17):3449-3454
New aromatic diamines [(1) and (2)] containing polycycloalkane structures between two benzene rings were synthesized by HCl-catalyzed condensation reaction of aniline hydrochloride and corresponding polycycloalkanone derivatives. The structures of diamines were identified by 1H-NMR, 13C-NMR, FTIR spectroscopy, and elemental analysis. The polyimides were synthesized from the obtained diamines with various aromatic dianhydrides by one-step polymerization in m-cresol. The inherent viscosities of the resulting polyimides were in the range of 0.34–1.02 dL/g. The polyimides showed good thermal stabilities and solubility. All the polymers were readily soluble in N-methyl-2-pyrrolidone, m-cresol, tetrachloroethane, etc. Some of them were soluble even in chloroform at room temperature. The glass transition temperatures were observed in the range of 323–363°C, and all of the polymers were stable up to 400°C under nitrogen atmosphere. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3449–3454, 1999 相似文献
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2-Methyl-4-(4-pyridyl)-3-butyn-2-ol ( 2 ) was prepared in 70% yield by the reaction of 4-bromopyridine with 2-methyl-3-butyn-2-ol in diethylamine in the presence of bis(triphenylphosphine)palladium(II) chloride and copper(I) iodide. Removal of the protective group in 2 by refluxing with sodium hydroxide in toluene yields (90%) 4-ethynylpyridine ( 3 ). Oxidative coupling of 3 in pyridine by dioxygen in the presence of copper(I) chloride produces a 92% yield of 1,4-bis(4-pyridyl)butadiyne. 相似文献
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R. A. Karakhanov M. R. Skurko T. Yu. Solov'eva L. Yu. Brezhnev L. F. Lapuka M. M. Vartanyan 《Chemistry of Heterocyclic Compounds》1984,20(2):128-132
2-Substituted spiro[1,3-dioxane-5,2-tetrahydrofurans] were obtained from 2,2-bis (hydroxymethyl) tetrahydrofuran, and their three-dimensional structures were investigated by 1H and 13C NMR spectroscopy. The tetrahydrofuran ring lies in the plane of symmetry of the 1,3-dioxane ring with an equatorial orientation of the oxygen atom.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 162–166, February, 1984. 相似文献
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Virgil Percec James H. Wang Shigeru Okita 《Journal of polymer science. Part A, Polymer chemistry》1992,30(3):429-438
The synthesis and the mechanism of oxidative polymerization of 2,2-bis[4-(1-naphthoxy)phenyl]propane ( 4 ) and 2,2-bis[4-(1-naphthyl)phenyl]propane ( 9 ) are presented. Both monomers polymerize by two different propagation steps. The first one represents a cation-radical dimerization of the naphthyl groups to dinaphthyl structure. H+[FeCl4]? generated from the first propagation step initiates a transalkylation reaction which provides structural units containing isopropylidenic groups inserted between phenyl and naphthyl, and between two naphthyl groups, respectively. Since the phenyl groups resulted from the second propagation reaction are unreactive in both the oxidative coupling and the transalkylation steps this polymerization reaction leads to polymers with low molecular weights containing phenyl chain ends. 相似文献
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Novel poly(arylene thioether)s were synthesised using the one pot polymerisation method from the bis(N,N-dimethyl-S-carbamate) of 2,2-bis(4-mercaptophenyl)propane and activated difluoro aromatic compounds. Each of the polymers, obtained in good yields and with fairly high molecular weights, were characterised by IR, GPC and NMR analyses. In particular, the NMR characterisation was performed using 1H NMR, 13C NMR, DEPT, 2D COSY and 2D HSQC experiments. To study the effect on the thermal properties of replacing the ethereal oxygen atoms with sulfur atoms, we have synthesised the counterparts, the poly(arylene ether)s, with similar molecular weights. We observed that the substitution of the ethereal oxygen atoms with sulfur atoms results in a slightly lower thermal stability for the poly(thioether ketone)s, both under nitrogen and in air, and does not modify the Tg values. For the poly(thioether sulfone), on the other hand, the thermal stability is equal to that of the poly(ether sulfone), while the Tg is 10 °C lower. Furthermore, each sample is completely amorphous, with the exception of one of the poly(thioether ketone)s (sample 1b), which shows the capacity to crystallise, even if with a very slow crystallisation kinetics. 相似文献
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Close packing conflict in a metastable polymorph of the pure title host (Z' = 2, melt crystal m) is resolved in the stable form (Z' = 1, sublimed crystal s) as O-H...O hydrogen bond changes to O-H...pi interaction. Melt crystallization and sublimation show a greater percentage of high Z' structures in CSD statistics. 相似文献
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A. V. Shastin L. B. Romanova L. T. Eremenko V. V. Zakharov G. V. Lagodzinskaya G. G. Aleksandrov I. L. Eremenko 《Russian Chemical Bulletin》2006,55(8):1452-1454
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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合成了2,2’-二(4-羟基苯基)丙烷为主体分子的四丁基铵包合物, [(n-C4H9)4N]+8226;[(C15H15O2)2H]-, 并通过单晶X射线衍射法对其进行了晶体结构测定, 发现该包合物的晶体存在两种同质异晶体. 结果表明, 晶型1属单斜晶系, C2/c空间群, 晶胞参数a=2.8199(2) nm, b=0.92730(8) nm, c=2.1450(3) nm, β=130.050(1)°, Z=4, R1=0.0771, wR2=0.2452; 晶型2属三斜晶系, P`1空间群, 晶胞参数a=1.0895(1) nm, b=1.2331(2) nm, c=1.7244(2) nm, α=108.137(2)°, β=94.458(2)°, γ=100.172(2)°, Z=2, R1=0.0697, wR2=0.2176. 晶型1中2,2’-二(4-羟基苯基)丙烷阴离子的氢键链构成管道式主体晶格, 正四丁基铵阳离子被包合在这些管道中; 晶型2中2个独立的2,2’-二(4-羟基苯基)丙烷阴离子分别形成氢键主体层, 它们交替排列并与夹在其间的正四丁基铵阳离子形成类三明治层状包合物. 相似文献