Aromatic Dicarboxylic Acids Research Articles

ISOTHERM ADSORPTION STUDY OF THE SOME DICARBOXYLIC ACID BY MANGANESE DIOXIDE

The adsorption process for Aliphatic and Aromatic dicarboxylic acid on manganese dioxide was studied briefly as a polluted material which produced in nature. The result showed that the anions of acid molecules were adsorbed on the surface of MnO2 depending on the pH of the solution and the shape of molecule. The aliphatic acids were partially enforcement with Langmuir isotherm and completely with Freundlech isotherm, but phthalic acid agreed with Langmuir only. The kinetic studies of pseudo first and second order were applied on this system. The adsorption process was endothermic except succinic acid, non- spontaneous and the nature of forces between the acid molecules and surface were physical in nature ,where the molecules in continues motion on surface and unsystematic except for succinic acid.

New aromatic oligoesters and their use in the synthesis of heat-resistant polyurethane coatings

For manufacturing new varnish polyurethane coatings with high hardness and elasticity at maintaining adhesion and strength properties oligoester diols were synthesized based on hydroxyethylated diphenylpropane derivatives and aromatic dicarboxylic acids.

Four cobalt(ii) coordination polymers with diverse topologies derived from flexible bis(benzimidazole) and aromatic dicarboxylic acids: syntheses, crystal structures and catalytic properties

Four metal–organic frameworks (MOFs) were obtained from the hydrothermal reaction of Co(ii) and with dicarboxylic acid and flexible bis(5,6-dimethylbenzimidazole) and characterized. The four MOFs exhibit distinct 2D or 3D structural frameworks.

Structures and properties of four coordination polymers constructed from 1,3-bis-(4-pyridyl)-propane and aromatic dicarboxylic acids

Four coordination polymers associated with 1,3-bis-(4-pyridyl) propane (bpp) and 5-methylisophthalic acid (H2mip) or 5-nitroisophthalic acid (H2nip) formulated as [Zn(bpp)(mip)]n (1), [Co(bpp)(mip)]n (2), [Zn2(bpp)2(nip)2]n (3) and [Co(bpp)(nip)(H2O)]n (4) have been synthesized under hydrothermal conditions. Single crystal analyses reveal that complex 1 presents a four-fold interpenetrating framework based on three-dimensional (3D) subunits with dia topology. Compound 2 has a 1D binuclear chain structure. Complex 3 shows 2D 44-sql layer structure packing in ABAB mode. Complex 4 exhibits a two-fold interpenetrating framework based on three-dimensional (3D) subunits with dia topology. These compounds have been characterized by infrared spectroscopy, elemental analysis, thermogravimetric analysis and powder X-ray diffraction. In addition, the photoluminescence of 1 and 3 and magnetic properties of 2 and 4 were investigated.

Redox-stable and visible/near-infrared electrochromic aramids with main-chain triphenylamine and pendent 3,6-di-tert-butylcarbazole units

A series of visible and near-infrared (NIR) electrochromic aramids with main-chain triphenylamine and pendent 3,6-bis(tert-butyl)carbazole units were prepared from the phosphorylation polyamidation reaction of 4,4′-diamino-4′′-(3,6-di-tert-butylcarbazol-9-yl)triphenylamine with various aromatic dicarboxylic acids. These aramids were readily soluble in many polar solvents and could be solution cast into flexible and strong films. They showed useful levels of thermal stability associated with relatively high glass-transition temperatures (Tg) (295–321 °C) and high decomposition temperatures (no significant degradation occurred before 450 °C in nitrogen or air). In addition, the polymer films showed reversible electrochemical oxidation with enhanced NIR contrast, fast switching time, and anodic green/blue electrochromic behaviors.

Effect of Cross-Linking Agent Chemistry and Coating Conditions on Physical, Chemical, and Separation Properties of PVA-Psf Composite Membranes

Composite nanofiltration membranes were formed by depositing ultra-thin, cross-linked polyvinyl alcohol (PVA) film on porous polysulfone (PSf) support membranes following a three step dip-coating procedure. The PVA coating films were cross-linked with aliphatic tricarboxylic acids (cis-/trans-aconitic) and aromatic dicarboxylic acids (phthalic, isophthalic, and terephthalic). Tricarboxylic acid cross-linked PVA was less crystalline and slightly more hydrophilic relative to PVA films cross-linked by aromatic dicarboxylic acids suggesting that the tricarboxylic acids are more effective is disrupting PVA crystallinity than the dicarboxylic acids. Cross-linked PVA-PSf composite membranes rejected NaCl and MgSO4 in the order: trans-aconitic acid < cis-aconitic acid < terephthalic acid < isophthalic acid < phthalic acid.

Enhancement of redox stability and electrochromic performance of aromatic polyamides by incorporation of (3,6‐dimethoxycarbazol‐9‐yl)‐triphenylamine units

ABSTRACTNew series aromatic polyamides with (carbazol‐9‐yl)triphenylamine units were synthesized from a newly synthesized diamine monomer, 4,4′‐diamino‐4″‐(3,6‐dimethoxycarbazol‐9‐yl) triphenylamine, and aromatic dicarboxylic acids via the phosphorylation polyamidation technique. These polyamides exhibit good solubility in many organic solvents and can be solution‐cast into flexible and strong films with high thermal stability. They show well‐defined and reversible redox couples during oxidative scanning, with a strong color change from colorless neutral form to yellowish green and blue oxidized forms at applied potentials scanning from 0.0 to 1.3 V. They show enhanced redox‐stability and electrochromic performance as compared to the corresponding analogs without methoxy substituents on the active sites of the carbazole unit. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 272–286

English

Air-dried, pulverized leaves of Gongronema latifolium were subjected to step wise fractionation using first, ethanol and subsequently fractionation of the dried ethanol extract using solvents of increasing polarity, n-hexane, chloroform, ethylacetate and ethanol. Column fractionation of the n-hexane extract using graded solvent mixture of n-hexane and ethylacetate in specified ratios, yielded four fractionates, one of which F2 was an oil. The F2 (oil) fraction was characterized by gas chromatography/mass spectral analysis. The effects of this oil fraction on alloxan- induced diabetes mellitus and indomethacin - induced ulceration were studied. The results obtained reveals that oil extract evoked significant inhibition of both alloxan- induced diabetes and indomethacin- induced ulcer in rats. The oil on analysis revealed content of essential fatty acyl esters and aromatic dicarboxylic acids, all of which are implicated in inhibiting hyperglycaemia and ulcer formation probably through oxidative reaction or through production of prostaglandins. &nbsp; Key words: Gongronema latifolium, essential fatty acids, diabetes mellitus, ulcer, prostaglandins.

Structural and theoretical studies of two novel sandwich-type two-dimensional silver(I) coordination polymers built up by aromatic and aliphatic dicarboxylic acid

Structural and theoretical studies of two novel sandwich-type two-dimensional silver(I) coordination polymers built up by aromatic and aliphatic dicarboxylic acid

A metal–organic coordination nanotube based on Co4-TC4A subunits and V-shaped aromatic dicarboxylic acids

The reaction of cobalt chloride with p-tert-butylthiacalix[4]arene (H4TC4A) and 1,3-di(4-carboxyphenyl)benzene (H2DCPB) in solvothermal condition results in a novel calixarene-based compound H{[Co4Cl(TC4A)](DCPB)2}. The compound was characterized by single crystal X-ray diffraction, EDS analysis, TG analysis and IR spectroscopy. The structure was featured with some zigzag chains containing the coordination nanotubular channels, which are constructed by bridging the shuttlecock-like Co4-TC4A secondary building units (SBUs) with the V-shaped DCPB ligands. In order to evaluate the porosity, the N2 sorption measurement was carried out.

Assembly of Nickel(II) and Manganese(II) Coordination Polymers based on a Energetic Aromatic Dicarboxylic Acid Ligand

AbstractThe complexes {[Ni(tnbpdc)(H2O)4]·2H2O}n (1) and {[Mn(tnbpdc)(H2O)4]·4H2O}n (2) (tnbpdc = 2, 2′,6, 6′‐tetranitro‐4, 4′‐biphenyl dicarboxylic acid) were synthesized and structurally characterized by IR spectrocopy, elemental analysis, and X‐ray diffraction. Complexes 1 and 2 adopt monodentate coordination modes and form two‐dimensional layer structures by hydrogen bonds. The thermal results exhibit that both complexes have high thermal stabilities, but different decomposition temperatures owing to the different central metal atoms. They can be applied as novel, structurally correlated heat‐resistant energetic materials.

Novel organosoluble aromatic polyetheramides bearing triphenylamine moieties: synthesis, electrochemistry, and electrochromism

A new class of electroactive polyetheramides (PEAs) with triphenylamine (TPA) units were prepared from 4,4′-bis(p-aminophenoxy)triphenylamine (4) and aromatic dicarboxylic acids via the phosphorylation technique. These PEAs were amorphous with good solubility in many organic solvents, such as NMP and DMAc, and could be solution-cast into strong polymer films. Their decomposition temperatures (T d) at a 10 % weight-loss in nitrogen and air were recorded at 545 ~ 570 °C and 531 ~ 560 °C, respectively. The glass-transition temperatures (T g) of all the PEAs were observed in the range of 227–234 °C by DSC. Cyclic voltammograms of the PEA films cast onto an indium-tin oxide (ITO)-coated glass substrate exhibited one reversible oxidation redox couples at 0.89 ~ 0.91 V versus Ag/AgCl in tetrabutylammonium perchlorate/acetonitrile solution. The PEA films revealed excellent electrochemical and electrochromic stability, with a color change from a colorless neutral form to pale orange and blue oxidized forms at applied potentials ranging from 0 to 1.06 V.

The use of de-aggregating agents in ZnSe mechanochemical synthesis

Conventional mechanochemical synthesis of zinc selenide, ZnSe nanoparticles was performed in a planetary ball mill by high-energy milling of zinc (Zn) and selenium (Se) powders with the de-aggregating agents ZnCl2 and phthalic acid (aromatic dicarboxylic acid, C8H6O4). Physical–chemical and optical properties of the prepared ZnSe nanoparticles were studied and compared. The mechanochemically synthesized products were characterized by X-ray diffraction analysis (XRD) that confirmed the presence of cubic-Stilleite and hexagonal ZnSe phases after 18, 25, 30, 40, 45 and 50 min of milling with various amounts of the added de-aggregating agents. Size of crystallites calculated from XRD patterns was from 20 to 31 nm for cubic ZnSe prepared with ZnCl2. For ZnSe synthesized with phthalic acid the crystallite size ranged from 16 to 73 nm. Size, phase composition, morphology, and crystallinity of ZnSe nanoparticles were studied by transmission electron microscopy (TEM) and selected area electron diffraction (SAED). Photoluminescence spectra (PL) at room temperature have shown a broad red emission bands, and the presence of de-aggregating agent has altered the intensity of the PL signal as well.

Bismuth Carboxylates with Brucite- and Fluorite-Related Structures: Synthesis Structure and Properties

Three new compounds of bismuth, [C4N2H10][Bi(C7H4NO4)(C7H3NO4)]·H2O, I, [Bi(C5H3N2O4) (C5H2N2O4)], II, and [Bi(μ2-OH)(C7H3NO4)], III, have been prepared by the reaction between bismuth nitrate and heterocyclic aromatic dicarboxylic acids, 2,6-pyridinedicarboxylic acid, 4,5-imidazoledicarboxylic acid, and 3,4-pyridinedicarboxylic acid, respectively, under hydrothermal conditions. The structures of all the compounds have linkages between Bi2O2 and the corresponding dicarboxylate forming a simple molecular unit in I, a bilayer arrangement in II, and a three-dimensional extended structure in III. The topological arrangement of the nodal building units in the structures indicates that a brucite-related layer (II) and fluorite-related arrangement (III) can be realized in these structures. By utilizing the secondary interactions, one can correlate the structure of III to a Kagome-related one. The observation of such classical inorganic related structures in the bismuth carboxylates is noteworthy. Lewis acid cata...

ChemInform Abstract: Regioselective Synthesis of Alkylarenes by Two‐Step ipso‐Substitution of Aromatic Dicarboxylic Acids.

AbstractThe reaction sequence consists of a Birch reduction/substitution followed by a rearomatization.

Stoichiometry, temperature, solvent, metal-directed syntheses of metal–organic frameworks based on flexible V-shaped methylenebis(3,5-dimethylpyrazole) and various aromatic dicarboxylate acids

Seven new metal–organic frameworks (MOFs), namely, {[Cd2(NDC)2(H2MDP)](H2O)} (1), [Cd(NDC)(H2MDP)] (2), {[Cd2(NDC)(HNDC)2(H2MDP)2](H2O)0.5} (3), [Cd(NH2–BDC)(H2MDP)2] (4), [Cd(NH2–BDC)(H2MDP)2] (5), [Cd(H2MDP)(Br–BDC)0.5(Br–HBDC)] (6), {[Co(H2MDP)(Br–BDC)](H2O)0.5} (7) (H2MDP = methylenebis(3,5-dimethylpyrazole), H2NDC = 1,4-naphthalenedicarboxylic acid, NH2–H2BDC = 2-amino-1,4-benzenedicarboxylic acid, Br–H2BDC = 2,5-dibromo-1,4-benzenedicarboxylic acid) have been controllably synthesized with H2MDP and different aromatic dicarboxylic acids by tuning metal-to-ligand molar ratios, temperature, solvents and metal ions. Compound 1 is a 3D 2-fold interpenetrated pcu framework of 412·63 topology constructed from paddle-wheel SBUs and trans-conformation H2MDP pillars, while compound 2 exhibits a 3D 3-fold interpenetrated diamondoid framework formed by single metal nodes via linear NDC2− and trans-conformation H2MDP ligands. Interestingly, compound 3 contains two different types of binuclear subunits formed by a pair of Cd(II) ions with partly deprotonated HNDC− ligands, and these subunits are further linked by completely deprotonated NDC2− and cis-conformation H2MDP ligands to form a 2D (4,4) network. Compounds 4 and 5 are solvent-induced structural isomers based on 2D (4,4) layers, and therefore have different solvent-accessible voids. Compounds 6 and 7, synthesized with different metal salts under similar solvothermal conditions, are characteristic of a 3D hydrogen-bonded supramolecular network, and a 3D 3-fold interpenetrated diamondoid network with equal number of left- and right-handed helical {Cd(H2MDP)}n chains further bridged together by linear Br–BDC2− ligands, respectively. In addition, the luminescent properties of solids 1–6 have been investigated at room temperature.

Oxalate-extended Cd2+–acylhydrazidate coordination polymers: synthesis, structure and fluorescence property

Two new oxalate-propagated Cd2+–acylhydrazidate coordination polymers [Cd2(ox)0.5(Hpth)(pth)(bpy)2] (ox = oxalate, pth = phthalhydrazidate, bpy = 2,2′-bypyridine) 1 and [Cd2(ox)(pdh)2]·H2O (pdh = pyridine-2,3-dicarboxylhydrazidate) 2 were obtained by simple hydrothermal self-assemblies of Cd(CH3COO)2, aromatic dicarboxylic acids, N2H4, and oxalic acid with or without bpy. The acylhydrazidate molecules (pth, pdh) originated from the acylation of N2H4 with aromatic dicarboxylic acids. X-ray analysis revealed that in both compounds, ox acts as the second linker, extending the metal–acylhydrazidate oligomers (tetranuclear for 1; dinuclear for 2) into the high-dimensional coordination polymers. In compound 1, the monoacylhydrazidate molecule with a −2 oxidation state was observed for the first time. In the solid state, only compound 2 emits light, while in an aqueous solution, both compounds emit light. The density functional theory (DFT) calculations indicate that whether in the solid state or in an aqueous solution, the emissions for compound 2 are both assigned to the charge transfer within the pdh molecule, corresponding to the charge transfer from the π* orbitals of the pyridine ring moiety to the π orbitals of the acylhydrazidate ring moiety. The solvent effect of water causes the blue shift from 525 nm to 405 nm. The blue-light emission (465 nm) for compound 1 in an aqueous solution is assigned to the charge transfer between the pth molecules, corresponding to the charge transfer from the π* orbitals of the benzene ring moiety of one pth molecule to the π orbitals of the acylhydrazidate ring moiety of another pth molecule. The Cd2+ center provides the path for charge transfer.

New Cd2+, Pb2+ complexes with acylhydrazidate molecules from in situ acylation reactions

Through employing the hydrothermal in situ acylation of N2H4 with aromatic dicarboxylic acids, four new acylhydrazidate-coordinated complexes, [Cd2(pth)4(phen)2(H2O)2]·H2O (pth = phthalhydrazidate; phen = 1,10-phenanthroline) 1, [Cd3(dcpth)6(phen)2(H2O)2] (dcpth = 4,5-dichlorophthalhydrazidate) 2, [Cd(pdh)2(H2O)2] (pdh = pyridine-2,3-dicarboxylhydrazidate) 3 and [Pb(sdpth)(phen)] (sdpth = 4,4'-sulfoyldiphthalhydrazidate) 4, were obtained. X-ray analysis revealed that (i) isomerization and deprotonation of acylhydrazide molecules also occurred; (ii) compound 2 possesses a one-dimensional (1-D) double-chain structure, in which dcpth exhibits three types of coordination modes; (iii) compound 4 shows a 1-D castellated single-chain structure; (iv) the adjacent uncoordinated acylamino groups form a hydrogen-bonded dimer, via which compounds 2-4 self-assemble into different two-dimensional (2-D) supramolecular networks. In the solid state, only compound 3 emits green light (λ(em) = 525 nm), while in an aqueous solution, compounds 1, 3 and 4 all emit light. Density functional theory (DFT) calculations indicate that the emission at 470 nm for compound 1 corresponds to a charge transfer within the phen molecule, whereas the emission at 400 nm for compound 3 corresponds to a charge transfer within the pdh molecule.

Synthesis and characterization of novel poly(amide-ether)s bearing imidazole pendants: study of physical and optical properties

Two new para-linked diether-diamines, bis(4-(4-amino-2-(4,5-diphenyl-1H-imidazol-2-yl)phenoxy) phenyl)methanone and bis(4-(4-amino-2-(4,5-diphenyl-1H-imidazol-2-yl)phenoxy) phenyl)hexafluoropropane, bearing two ortho-linked phenyl-substituted imidazole pendants and trifluoromethyl groups were synthesized by the nucleophilic chlorodisplacement reaction of the synthesized 2-(2-chloro-5-nitrophenyl)-4,5-diphenyl-1H-imidazole with 4,4′-dihydroxybenzophenone or 4,4′-(hexafluoroisopropylidene)diphenol in refluxing DMAc in the presence of potassium carbonate. These diamines were utilized to prepare a series of novel poly(amide-ether)s (PAEs) via direct phosphorylation polycondensation with aliphatic and aromatic dicarboxylic acids. The polymeric samples were readily soluble in a variety of organic solvents and formed low-colored and flexible thin films via solution casting. These polymers showed glass-transition temperatures (Tgs) between 204 and 308 °C. Thermal behaviors of the PAEs were characterized by thermogravimetric analysis, and the 10 % weight loss temperatures were found to be in the range of 330–450 °C in N2. The PAEs exhibited fluorescence emission in solution and in solid state with maxima around 423–494 nm and with the quantum yields in the range of 6–28 %.

Synthesis of Soluble, Curable, and Thermally Stable Aromatic Polyamides Bearing Thiourea and Pendent 4-Pyridylformylimino Groups

A new aromatic dicarboxylic acid monomer 4-pyridylformylimino-N-(phenyl,2′,5′ – dicarboxylic acid) (PPDC) containing pyridine and azomethine units was synthesized through a simple one-step condensation reaction between 2-aminoterephthalic acid and 4-pyridinecarboxaldehyde. A series of new polyamides was prepared through the direct one-pot phosphorylation polycondensation of PPDC with simple aromatic commercial diamines and diamines bearing phenylthiourea groups. The polyamides were characterized by FT-IR, 1H-NMR, and 13C-NMR spectroscopy. Thermal stability of the polymers was evaluated using thermogravimetric analysis. The polyamides with inherent viscosities in the range of 0.30–0.51 dL/g showed an outstanding solubility in various solvents such as 1-methyl-2-pyrrolidone (NMP), dimethly sulfoxide (DMSO), N,N-dimethylformamide (DMF), N,N-dimetylacetamide (DMAc), and pyridine. The cured polyamides displayed significantly higher thermal stability than the uncured polyamides. The conductivity of the polyamides, when blended with 20% by weight of doped polyanilines, was in the range 3.09–4.21 × 10−3 S cm−1.