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1.
Mitsuru Ueda Tetsuya Abe Mitsuo Oda 《Journal of polymer science. Part A, Polymer chemistry》1992,30(9):1993-1998
Aromatic poly(thioether ketone)s were prepared by the direct polycondensation of aromatic dicarboxylic acids with aryl compounds containing ether or sulfide structures using phosphorus pentoxide/methanesulfonic acid (PPMA) as a condensing agent and solvent. Polycondensation proceeded smoothly and produced aromatic poly(thioether ketone)s with inherent viscosities up to 0.73 dL/g. The synthesis of substituted aryl ketones by the reaction of substituted benzoic acids with aryl compounds in PMMA was studied in detail to demonstrate the feasibility of the reaction for polymer formation. The thermogravimetry of the aromatic poly(thioether ketone)s showed a 10% weight loss in air and nitrogen at around 450 and 460°C, respectively. © 1992 John Wiley & Sons, Inc. 相似文献
2.
铜配合物具有多变的配位结构,可活化小分子,可用于氧转移、氧化加成、新陈代谢、均相催化等许多领域。还可以用作金属酶的化学模拟和配合物结构及反应性能研究方面[1-3]。本文以2,3 二羧酸 吡啶为辅助配体及[(PPh3)2Cu(BH4)]作为起始原料,室温下,通过取代反应合成了单核铜(Ⅰ)配合物[(PPh3)2Cu(C7H4NO4)],经元素分析、电导、光电子能谱、红外光谱及单晶XRD方法对配合物进行了表征。1 实验部分1 1 仪器和试剂意大利ERBA 1106元素分析仪,JA96 970等离子光谱仪,Nicolet170SX分析仪(CsI压片),AV 300Bruker分析仪(CDCl3溶剂,8… 相似文献
3.
4.
Three new aromatic diester–dicarboxylic acids containing furan rings, namely, benzofuro[2,3-b]benzofuran-2,9-dicarboxyl-bis-phenyl ester-4,4′-dicarboxylic acid, benzofuro[2,3-b]benzofuran-2,9-dicarboxyl-bis-phenyl ester-3,3′-dicarboxylic acid and benzofuro[2,3-b]benzofuran-2,9-dicarboxyl-bis-naphthyl ester-2,2′-dicarboxylic acid were synthesized by the reaction of benzofuro[2,3-b]benzofuran-2,9-dicarbonyl chloride with 4-hydroxybenzoic acid, 3-hydroxybenzoic acid and 3-hydroxy-naphthalene-2-carboxylic acid, respectively. Diester–dicarboxylic acids were characterized by FT-IR and NMR spectroscopy and elemental analyses. Then, these monomers were converted to aromatic copoly(ester–amide)s by their reaction with various aromatic diamines via the direct polycondensation. These polymers were characterized by viscosity measurements, solubility tests, FT-IR, Ultraviolet and 1H-NMR spectroscopy and thermogravimetry. The polymers with inherent viscosities in the range of 0.16–0.37 dl/g in dimethyl sulfoxide at 30 °C were obtained in high yield. Most of them dissolved readily at room temperature in polar solvents. The synthesized copoly(ester–amide)s possessed glass-transition temperatures from 210–255 °C. The copoly(ester–amide)s exhibited excellent thermal stabilities and had 10% weight loss at temperature above 295 °C under nitrogen atmosphere. 相似文献
5.
碳铂类似物的合成,表征及对大鼠W—256肉瘤的抑制作用 总被引:2,自引:0,他引:2
合成了十八种〔PtA_2X〕·yH_2O,其中A分别为NH_3、CH_3NH_2、1/2乙二胺和1/2(2,3-二甲基-2,3-丁二胺),X分别为1,1-环丙烷二羧酸根(CPrDCA)、2-甲-1,1-环丙烷二羧酸根(2-M-CPrDCA)、2-甲-1,1-环丁烷二羧酸根(2-M-CBDCA)、1,2-环戊烷二羧酸根(CPDCA)和1,1-环已烷二羧酸根(CHDCA),并进行了表征。测定了配合物抑制大鼠W-256肉瘤的活性,发现配合物〔Pt(NH_3)_2X〕系列按X不同有以下的活性次序:CPrDCA>2-M-CPrDCA>CPDCA>CBDCA(碳铂)≥2-M-CBDCA。 相似文献
6.
0IntroductionItiswellknownthatcobalt?candisplayvariouscoordinationpolyhedron,theusualcoordinationnum-bervaryingfromfourtosix,whilemanyreportsonthecrystalandmolecularstructureareofsimplecobalt?complex,relativelyfewcasesconcernheteronuclearcomplexes.Recently,somestructuresofheteronuclearcompoundscontainingpyridine-2,6-dicarboxylicacidhavebeendetermined犤1~4犦,becauseoftheirimportantroleincoordinationchemistry,catalyticreactions,magneticmaterialandbiologicalsystem.Wereporthereanovelstructureofco… 相似文献
7.
本文研究了二茂钛含氟长链有机酸衍生物(1~3)和具有环状结构的新型二茂钛全氟有机酸(4~7)的电子轰击质谱(EIMS)和负离子化学电离质谱(NICIMS)。在EI谱中出现弱的或不出现M~+,1~7均以CpTiF_2离子为基峰。高质量区的主要特征碎片离子有[M-·cp]~+、[M-R]~+(1~3)和氟重排离子。在低质量区出现一系列二茂钛及茂钛氟重排离子。 1、4~7的NICI(CH_4)质谱中,4、5出现强的M~-离子峰,1出现[M-1]-离子峰,有两个钛的环状结构化合物6和7出现双电荷M~=离子峰,而不出现M~-。 相似文献
8.
Stoikov I. I. Gafiullina L. I. Ibragimova D. Sh. Antipin I. S. Konovalov A. I. 《Russian Chemical Bulletin》2004,53(6):1172-1180
New calix[4]arenes, di- and tetrasubstituted at the lower rim, with different functional groups were synthesized. They were studied as carriers of a series of dicarboxylic and -hydroxycarboxylic acids through a liquid impregnated membrane. The calix[4]arenes under study are capable of molecular recognition of oxalic acid in the series of structurally similar dicarboxylic and -hydroxycarboxylic acids. The regularities found make it possible to change purposefully the receptor ability of 1,3-disubstituted calix[4]arenes by variation of the nature of substituents. 相似文献
9.
Xian‐Zhong Sun Zhen‐Li Huang He‐Zhou Wang Bao‐Hui Ye Xiao‐Ming Chen 《无机化学与普通化学杂志》2005,631(5):919-923
Two new coordination polymers [Cd(tdc)(bpy)(H2O)]n ( 1 ) and [Cd(tdc)(phen)]n ( 2 ) (H2tdc = thiophene‐2,5‐dicarboxylic acid, bpy = 2,2′‐bipyridine and phen = 1,10‐phenanthroline) have been synthesized under hydrothermal condition. Their crystal structures have been established by X‐ray single‐crystal diffraction. Complex 1 crystallizes in the orthorhombic space group Fdd2 with a = 14.757(7), b = 45.38(2), c = 10.518(5) Å, V = 7044(6) Å3, Z = 16; 2 in the monoclinic space group P21/c with a = 7.262(1), b = 21.970(2), c = 10.051(1) Å, β = 105.01(1)°, V = 1548.8(2) Å3, Z = 4. Both of them are double‐stranded chains and further assembled into three‐dimensional networks by π‐π stacking interactions. 1 and 2 are stable in air, and show blue photoluminescence at 415 nm and 410 nm, respectively. 相似文献
10.
Shul"gin V. F. Zlatogorskii S. M. Zub V. Ya. Larin G. M. 《Russian Chemical Bulletin》2002,51(12):2273-2276
The binuclear vanadyl(ii) complexes [(VO)2·2Py·2EtOH]·mH2O with acyldihydrazones of salicylaldehyde (H4L) and dicarboxylic acids were synthesized and studied. In these complexes, two chelate vanadyl(ii) complexes with the tridentate bicyclic ligands are linked to each other by the polymethylene bridges —(CH2)
n
— of different lengths varying from one to four units. The ESR spectra of solutions of these complexes, unlike those of analogous copper(ii) complexes, have an isotropic signal with an eight-line hyperfine structure (g = 1.972, a
V = 93·10–4 cm–1) typical of monomeric vanadyl complexes, which indicates that no exchange interactions occur between the paramagnetic centers through the polymethylene chain. 相似文献