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1.
4-(1H-imidazol-1-yl) benzoic acid and its coordination polymers [M(IBA)Cl] n (M?=?Zn (1) and Co (2)) have been synthesized. Compounds 1 and 2 were obtained under ionothermal conditions and possess a 2-D laminar [M(IBA)] n layer based on M2(CO2)2 building blocks with coordinated chloride completing tetrahedral coordination of the metal. Compound 1 exhibits two photoluminescence emission peaks at 410 and 510?nm. The low-energy emission can be attributed to ligand-centered transition and the high-energy band can be assigned to ligand-to-metal charge transfer between the aromatic systems of the organic ligands and the 4s orbitals of Zn(II). The role of the ionic liquid in ionothermal synthesis and crystallization of 1 and 2 are briefly discussed.  相似文献   

2.
The possibility of incorporation of 4-(pyrrole-1-yl) benzoic acid, PyBA, during electrodeposition of poly(3,4-ethylenedioxythiophene), PEDOT, is demonstrated here. The resulting novel composite material has been fabricated as moderately thin (ca 200–300 nm thick) PEDOT/PyBA film on electrode surface. As evidenced from scanning tunneling microscopy (STM) and scanning electron microscopy (SEM), morphology of the composite film is dense and granular, and it is composed of larger granules in comparison to the PyBA-free PEDOT film. It is apparent from infrared reflectance absorption spectroscopy and spectroelectrochemical measurements that the PEDOT/PyBA composite film cannot be viewed as simple mixtures of PEDOT and PyBA components. Some specific (chemical) interactions between PEDOT and PyBA can be expected. The conducting polymer serves as a robust, positively charged conductive polmer matrix for anionic (carboxylate-group derivatized) partially polymerized PyBA structures. Upon incorporation of PyBA, the overall stability of PEDOT film (resistance to dissolution during prolonged voltammetric potential cycling) has been improved. The fact, that the composite PEDOT/PyBA film is capable of preconcentrating (under open circuit conditions) both cations (Cu2+) or anions implies the presence of both free (available for binding) carboxylate groups and positively charged PEDOT sites. The presence of PyBA in PEDOT seems to facilitate charge propagation in the composite film. “Contribution to the International Workshop on Electrochemistry of Electroactive Materials (WEEM-2006), Repino, Russia, 24–29 June 2006”.  相似文献   

3.
在氧化铜和溴化铜存在的条件下, 4-[1,2-(2-吡啶基)亚甲硫基]-苯甲酸(L′)经原位消去反应, 形成了一个新的有机配体4-[1,2,2-(2-吡啶基)-(2-吡啶亚甲基)亚甲硫基]-苯甲酸(L), 并与铜形成配位聚合物[Cu2(L)Br2]n(1){L=4-[1,2,2-(2-吡啶基)-(2-吡啶亚甲基)亚甲硫基]-苯甲酸}, 通过红外光谱、元素分析和X射线单晶衍射等手段对其结构进行了表征.  相似文献   

4.
A new dialdehyde 1,1-bis[4-(4-benzaldehyde oxy)-3-methyl phenyl] cyclopentane (BBMPC) was synthesized starting from cyclopentanone and O-cresol to give 1,1-bis(4-hydroxy-3-methyl phenyl)cyclopentane (BHMPC); followed by reaction with 4-fluorobenzaldehyde in N, N-dimethyl formamide (DMF), containing anhydrous potassium carbonate. New series of poly(ether-azomethine)s were synthesized from (BBMPC) with different diamines such as 4,4′- diamino diphenyl ether (ODA); 4,4′-diaminodiphenyl methane (MDA); 4-aminophenyl sulfone (SDA); p-phenylene diamines (p-PDA), etc. in N, N’- dimethyl acetamide (DMAc) with 5 wt% LiCl by the solution polycondensation method. Inherent viscosities of these polymers were in the range 0.20 to 0.38 dL/g indicating formation of moderate molecular weights. These polymers exhibited good solubility in various polar aprotic solvents such as N-methyl-2-pyrrolidone (NMP), DMAc, DMF, etc. However some polymers showed partial solubility in DMF and DMAc. X-Ray diffraction pattern of polymers showed amorphous nature. Thermal stability was assessed by 10% weight loss temperature and the degradation temperature of the resultant polymers falls in the ranges from 444-501°C in nitrogen. The glass transition temperature was in the range of 155-205°C. The structure-property correlation among these polyazomethines were studied; in view of their potential applications as high performance polymers.  相似文献   

5.
A new dinuclear complex [Tb2(BA)6(2,2′-bipy)2] (BA=4-(trifluoromethyl)benzoic acid, 2,2′-bipy=2,2′-bipyridine) has been synthesized. The complex was characterized by X-ray single-crystal structure analysis. The complex is a dimer with an inversion center. In the complex, two Tb3+ ions are linked by four carboxylate groups of BA ligands in bridging-bidentate coordination mode. Each Tb3+ ion is eight-coordinated with two nitrogen atoms from one 2,2′-bipy molecule, four oxygen atoms from four bridging-bidentate BA ligands and two oxygen atoms from one chelating-bidentate BA ligand. Intermolecular hydrogen bonds are formed in the crystal. The complex exhibits strong green fluorescence under ultraviolet light and the fluorescence spectrum consists of four lines peaking at 489, 545, 584 and 620 nm, which are corresponding to the 5D47Fj (j=6~3) transitions of Tb3+ ion, respectively. CCDC: 727763.  相似文献   

6.
A new cardo diamine monomer, 5,5-bis[4-(4-aminophenoxy)phenyl]-4,7-methanohexahydroindane (II), was prepared in two steps with high yield. The monomer was reacted with six different aromatic tetracarboxylic dianhydrides in N,N-dimethylacetamide (DMAc) to obtain the corresponding cardo polyimides via the poly(amic acid) precursors and thermal or chemical imidization. All the poly(amic acid)s could be cast from their DMAc solutions and thermally converted into transparent, flexible, and tough polyimide films which were further characterized by x-ray and mechanical analysis. All of the polymers were amorphous and the polyimide films had a tensile strength range of 89–123 MPa, an elongation at break range of 6–10%, and a tensile modulus range of 1.9–2.5 GPa. Polymers Vc, Ve, and Vf exhibited good solubility in a variety of solvents such as N-methyl-2-pyrrolidinone (NMP), DMAc, N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), pyridine, γ-butyrolactone, and even in tetrahydrofuran and chloroform. These polyimides showed glass-transition temperatures between 274 and 299°C and decomposition temperatures at 10% mass loss temperatures ranging from 490 to 521°C and 499 to 532°C in nitrogen and air atmospheres, respectively. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2815–2821, 1999  相似文献   

7.
(E)-4-(4-Methoxyphenoxy)-4-oxobut-2-enoic acid and its Ce(IV), Th(IV), and UO2(II) complexes were synthesized and characterized by MS, elemental analysis, IR, UV, TG-DTA, and NMR. The complexes have composition [CeL2(OH)2 · 2H2O] · H2O, [ThL2(OH)2 · 2H2O] · H2O, and [UO2L2 · 2H2O] · H2O. Molar conductance data confirm that the three complexes are nonelectrolytes. The IR and NMR results show that the carboxylates coordinate to the metal ions bidentate, and the ester carboxylic groups do not take part in coordination. Luminescence spectra of the ligand and complexes in DMSO at room temperature were also studied showing strong luminescence of the metal ions.  相似文献   

8.
以对碘苯甲酸为原料,采用“一锅法”合成高价碘试剂4-二氯碘苯甲酸(1),其结构经1H NMR和IR确证。考察了其对取代苯甲醇的氧化性能。结果表明:1对4-(二甲氨基)苄醇的氧化性能最高,收率93%。  相似文献   

9.
A fluorine-containing diamine, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane (BAPPH) ( II ), was synthesized in two steps on condensation of 2,2-bis(4-hydroxyphenyl)hexafluoropropane with p-chloronitrobenzene in the presence of potassium carbonate, giving 2,2-bis[4-(4-nitrophenoxy)phenyl]hexafluoropropane ( I ), followed by reduction with hydrazine monohydrate/Pd—C. Fluorine-containing polyamides and copolyamides having inherent viscosities 0.41–0.88 dL g−1 were prepared by direct polycondensation of BAPPH with various aromatic diacids or with mixed diacids, by triphenyl phosphite and pyridine in N-methyl-2-pyrrolidinone (NMP). The polyamides were examined by elemental analysis, IR spectra, inherent viscosity, x-ray diffraction, solubility, DSC, and TGA. The diffractogram showed that the polyamides were crystalline except IVb , IVc , IVf , and Vc . Almost all polyamides were soluble in polar aprotic solvents. The polymers obtained from BAPPH lost no mass below 350°C, with 10% loss of mass being recorded above 467°C in nitrogen. These aromatic polyamides had glass transition temperatures in the 221–253°C range. © 1996 John Wiley & Sons, Inc.  相似文献   

10.
Copolyesters of 4-hydroxybenzoic acid (HBA) and 3-(4'-hydroxyphenoxy)benzoic acid were prepared by two different procedures. Either the acetyl derivatives were polycondensed in bulk at temperatures up to 300°C or they were polycondensed in an inert reactions medium (Marlotherm-S) at 340°C. Two analogous series of copolyesters were synthesized from 4-acetoxybenzoic acid (4-HBA) and 4-(3'-acetoxyphenoxy)benzoic acid. The copolyesters were characterized by elemental analyses, inherent viscosities, 1H- and 13C-NMR spectroscopy, WAXS and DSC measurements, and by optical microscopy. All copolyesters synthesized in solution were highly crystalline materials which were neither meltable nor soluble. Part of the copolyesters prepared by polycondensation in bulk were semi-crystalline, meltable, and soluble. The copolyester derived from 3-(4'-hydroxyphenoxy)benzoic acid proved to be thermotropic forming a nematic melt, whereas the isomeric copolyesters of 4-(3'-hydroxyphenoxy)benzoic acid only formed isotropic melts. © 1993 John Wiley & Sons, Inc.  相似文献   

11.
从4-羟基偶氮苯出发,依次与2-氯乙醇、丙烯酰氯反应,合成了2-(4-苯基偶氮苯氧基)乙基丙烯酸酯(PAPEA)。接着以PAPEA为单体,二硫代苯甲酸异丁腈酯(CPDB)为链转移剂,偶氮二异丁腈(AIBN)为引发剂,利用可逆加成-断裂链转移(RAFT)聚合法合成了聚[2-(4-苯基偶氮苯氧基)乙基丙烯酸酯](PPAPEA)均聚物,同时考察了反应时间、引发剂和链转移剂浓度等因素对聚合反应的影响。利用FT-IR、1H-NMR和GPC等对单体和聚合物的结构进行了表征,并利用UV对聚合物的光响应性能进行了测试。结果表明,PAPEA的聚合反应动力学曲线呈良好的线性关系,分子量分布较窄(小于1.3);均聚物在紫外光照下的异构化速率随分子量的增大而减缓,而其在自然光下的回复速率变化不大。  相似文献   

12.
肖雪英  韦永勤  郑文旭  吴克深 《结构化学》2011,30(11):1543-1550
Four novel 1D lanthanide coordination polymers with formula [Ln(3,4-pybz)3(H2O)2· H2O]n (Ln = 1 Sm; 2 Eu; 3 Tb; 4 Dy, 3,4-Hpybz = 3-(pyridin-4-yl)benzoic acid) have been synthesized by hydrothermal reactions of lanthanide oxide and 3-(pyridine-4-yl) benzoic acid. Single-crystal X-ray diffraction shows that the four compounds are isostructural. They all crystallize in a monoclinic system, space group P1. They have a doubly carboxylate-bridged infinite-chain structure with alternating Ln-(carboxylate)2-Ln linkages and one chelating carboxylate group on each metal center. The Ln ion also combines to two water molecules to form an eight-coordinate square antiprismatic geometry. The pyridine nitrogen atoms of the ligand do not coordinate to the metal centers but direct the formation of a 3D network through hydrogen bonding with coordinated water molecules. The photoluminescent properties of 2 and 3 have been also studied.  相似文献   

13.
利用水热方法合成了一个新的由草酸和对咪唑基苯甲酸混合配体共同构筑的镉配合物[Cd(L)(C2O4)0.5(H2O)]n,并通过元素分析、红外光谱和X-射线单晶衍射方法确定了该化合物的晶体结构。结构分析表明该化合物属于单斜晶系,空间群P21/n,晶胞参数a=1.167 60(14)nm,b=0.841 80(15)nm,c=1.246 90(15)nm,β=105.404(2),V=1.1815(3)nm3,Z=4,R1=0.0312,ωR2=0.063 1。标题化合物包含一个格子状的二维层结构,三组相同的二维层相互穿插而构筑了三重互穿的框架,同时研究了化合物的光致发光性能。  相似文献   

14.
2-(N-naphthylamido)benzoic acid was synthesized by the reaction of phthalic anhydride with naphthylamine in glacial acetic acid at room temperature. Complexes 19 were synthesized under reflux in good yield with general formula R4? n SnL n (R = Me, n-Bu, Ph, n-Oct, Bz and n = 2, 3), which were studied by microanalysis, IR, NMR (1H, 13C, 119Sn), and mass spectrometry. Cytotoxicity of the synthesized compounds was checked against Brine-shrimp larvae. In vitro activities against some Gram-positive and Gram-negative bacteria and fungi were also determined. Antimicrobial activities show that species with tetrahedral geometry in solution are more toxic.  相似文献   

15.
Condensation of 2-cyanomethylbenzoic acid with anthranilic acids gave a series of 2-(4-oxo-3,4-dihydro-2-quinazolinylmethyl)benzoic acids which are structural analogs of the alkaloid glycosminine (2-benzyl-1,2-dihydro-4-quinazolone).  相似文献   

16.
在乙醇体系中,由主配体4-[(1,3-二氧代丁基)氨基]苯甲酸(H2L,C11H11NO4)、稀土硝酸盐及辅助配体邻菲啰啉(phen)反应合成了两个系列8个配合物[Ln2(L)3(H2O)4]n(Ln=Sm(1),Eu(2),Tb(3),Dy(4));[Ln2(NO3)2(L)2(phen)2]n(Ln=Sm(5),Eu(6),Tb(7),Dy(8))。用元素分析、红外光谱、摩尔电导、热重分析进行表征,确定了产物的化学组成,推断了相应的结构。测定了室温时固体产物的激发和发射光谱,结果表明:由主辅配体共同配位的三元配合物的发光强度好于无辅助配体参与的二元配合物。测定了三元配合物的荧光寿命,其中铕和铽配合物显示较长的荧光寿命。  相似文献   

17.
邻氮基苯甲酸;缩合反应;卤代-2-(3-甲基-5-取代-4H-1;2;4-三唑-4-基)-苯甲酸的合成  相似文献   

18.
Hu K  Chen K  Zhang H  Liu J  Zhao W  Zhang S 《色谱》2011,29(11):1093-1097
选用自制的对叔丁基杯[4]-1,2-冠-4 (Cx4-4)键合固定相,通过改变流动相中甲醇比例和pH值,考察了苯甲酸(BAH)在Cx4-4键合固定相上的保留行为。采用量子化学计算方法中密度泛函理论(DFT)中的B3LYP/STO-3G*基组对建立的Cx4-4与BAH相互作用的超分子构型进行了优化和频率计算,得到了超分子相互作用的稳定化能和吉布斯自由能;根据计算结果对BAH在杯芳烃固定相上的保留机理进行了研究,并进一步建立了食品中BAH在Cx4-4色谱柱上的高效液相色谱(HPLC)分离分析方法。  相似文献   

19.
环己烷类液晶因具有高度的稳定性,较宽的相列相温区而受到人们的青睐。反-4-(反-4’-正丙基环己基)环己醇(trans-3HHE)是一种合成环己烷类液晶的重要中间体,它可通过酶选择性催化和顺式构型异构化二种方法合成。文献报道顺式构型异构化法是:4-(反-4’-正丙基环己基)苯酚以铑/碳或铑/氧化铝为催化剂,在酸性介质条件下进行加氢反应,  相似文献   

20.
L-半胱氨酸盐酸盐与二硫化碳, 氢氧化钠在硝酸铅存在下进行成环反应得到(R)-四氢噻唑-2-硫酮-4-羧酸产率76% , 后者与 醇在硫酸铁水合物催化下反应得到(R)-四氢噻唑-2-硫酮-4-羧酸酯, 产率40~82% .  相似文献   

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