M-phthalic Acid Research Articles

Highly thermostable mixed lanthanide organic frameworks with high quantum yield for warm white light-emitting diodes.

A mixed lanthanide organic framework was prepared via hydrothermal methods using m-phthalic acid (m-H2BDC), 1,10-phenanthroline (1,10-Phen), and Ln3+ ions, formulated as [HNMe2][Eu0.095Tb1.905(m-BDC)3(phen)2] (ZTU-6). The structure and stability of ZTU-6 were characterised by X-ray diffraction (XRD) and thermogravimetric analysis (TGA), which revealed a three-dimensional pcu topology with high thermal stability. Fluorescence tests showed that ZTU-6 emitted orange light with a high quantum yield of 79.15%, and it can be effectively encapsulated in a light-emitting diode (LED) device emitting orange light. In addition, ZTU-6 was found to be compatible with BaMgAl10O17:Eu2+ (BAM) blue powder and [(Sr,Ba)2SiO4:Eu2+] silicate yellow and green powder to create a warm white LED with a high colour rendering index (CRI) of 93.4, a correlated colour temperature (CCT) of 3908K, and CIE coordinates of (0.38, 036).

Regulation of the Assembled Structure of a Flexible Porphyrin Derivative Containing Tetra Isophthalic Acids by Coronene or Different Pyridines.

Based on previous research, a new coassembly formed by a porphyrin derivative (IPETPP), which contains a flexible substituent of m-phthalic acid, is observed with coronene (COR) molecules at a higher concentration. Besides, a fresh IPETPP self-assembly formed at a lower concentration and another new coassembly with COR molecules are obtained. Moreover, the addition of a series of bipyridines alters the diamond arrangement of IPETPP, which enhances the stability of the two-component structures. It is unprecedented that bipyridine derivatives break intermolecular hydrogen bonds containing m-phthalic acid substituents. All the coassemblies are investigated by scanning tunneling microscopy on a highly oriented pyrolytic graphite. Combined with density functional theory, the formation mechanism of the assembled structures is revealed. These results would contribute to understanding the interfacial crystal behaviors and probably provide an efficient pathway to regulate the binary structures.

Luminescence sensing for one Zn MOF and improvement of hydrogen evolution performance by cobalt doping

One zinc coordination polymer based on 5-(4-(tetrazol-5-yl) phenyl) m-phthalic acid (tpia) was synthesized. It was characterized by powder X-ray diffraction. Fluorescence titration experiments show that 1 is a multifunctional probe for metal ions and antibiotics. In addition, its electrocatalytic performance was improved and optimized by doping cobalt ions and pyrolysis, that is 1-Co-700. 1-Co-700 has a low initial potential (−423 ​mV), Tafel efficiency (101.9 ​mV·dec−1) and good cycle stability (stable after at least 1000 cycles).

Copper doped terbium metal organic framework as emitter for sensitive electrochemiluminescence detection of CYFRA 21-1

Lanthanide metal organic frameworks (L-MOFs) are emerging as promising electrochemiluminescence (ECL) emitters for bioanalysis. This work proposed a copper doped terbium MOF as a luminescent tag for construction of a “signal-on” ECL immunosensing method. The Tb–Cu-PA MOF was prepared using Tb3+ and Cu2+ ions as metal linkers and m-phthalic acid as bridge ligand, and exhibited strong ECL emission with K2S2O8 as a coreactant. The immunosensor was prepared by immobilizing capture antibody on Pd nanoparticles modified Ni–Co layered double hydroxide (Pd-ZIF-67@LDH) nanoboxes, which showed strong electrocatalytic activity toward the reduction of S2O82− for amplifying the ECL signal. Upon the sandwich-typed immunoreactions, Tb–Cu-PA MOF labeled antibody was introduced onto the immunosensor for sensitive ECL detection of target protein. Using cytokeratin 19 fragment 21–1 (CYFRA21-1), a representative lung cancer biomarker, as target model, the ECL immunosensing method showed a linear range of 0.01–100 ng/mL and a detection limit of 2.6 pg/mL (S/N = 3). This immunosensing strategy highlighted the advances of using luminescent and electroactive MOFs in the developments of highly efficient immunosensors for bioanalysis.

On the effects of organic-acids isomers on temperature-responsiveness in wormlike micelles (WLMs) systems

Responsive wormlike micelles (WLMs) consisted of cationic surfactants and organic-acids are fascinating due to their reversible molecular recognition properties. However, it is unknown how the structure of organic-acids alters the stimuli-responsiveness of WLMs systems. Herein, the peculiar nature of temperature-responsive behaviors in three WLMs systems were systematically investigated. These were manufactured by combining N-erucamidopropyl-N,N-dimethylamine (UC22AMPM) with isomers of organic-acids: o-phthalic acid (o-PA), m-phthalic acid (m-PA) and p-phthalic acid (p-PA) at molar ratio of 2:1 (named as o-EAPA, m-EAPA and p-EAPA respectively). The phase behaviors, macro- and micro-rheology, as well as the mechanism of temperature-responsiveness were explored by visual inspection, rheological and optical methods. The results showed that the three systems exhibited different responsiveness with increase of temperature. Among them, the viscosity and viscoelasticity of o-EAPA were gradually decreased with temperature increase from 30 °C to 90 °C. On the other hand, those of p-EAPA were firstly increased and subsequently decreased, exhibiting the highest viscosity during the heating process. This peculiar phenomenon was attributed to the hydrophilic difference of organic-acids isomers, leading to variations of micelle transitions upon temperature increase. This study is the first report of aromatic-acids isomers inducing different on temperature-responsiveness, and finding beneficial for the development of responsive WLMs for different applications.

Open-Framework Zn Compound with Cationic-π Interaction: Photochromism and Benzene Series Detection.

Photochromic open-framework compounds are of potential application in detection/sensors. The issue of improving the detection limits has received much attention. We synthesized a new open-framework Zn compound, namely, compound 1 ([Zn(MQ)(IPA)Cl]·5H2O) (MQ = N-methyl-4,4'-bipyridinium, IPA = m-phthalic acid), which showed a 1D channel structure by a cationic-π interaction. It is noteworthy that this compound is an effective detector for aniline though luminescence emission, which exhibited unprecedented detection limits in photochromic open-framework compounds.

A smart sensing Zn(ii) coordination polymer based on a new viologen ligand exhibiting photochromic and thermochromic and multiple solid detection properties

A multi-functional one-dimensional chain coordination polymer synthesized from Zn(ii), m-phthalic acid and a novel viologen ligand.

A sustainable water-tolerant catalyst with enhanced Lewis acidity: Dual activation of Cp2TiCl2 via ligand and solvent

A new strategy was developed to enhance the activity of titanocene dichloride for the synthesis of 2,4-disubstituted-3H-benzo[b]-[1,4]diazepine derivatives by using Cp2TiCl2 as a pre-catalyst. The titanocene was activated in situ in the catalytic system via the coordination with m-phthalic acid and alcohol solvent accompanied with the secession of a cyclopentadienyl ring, leading to the formation of an activated species, [CpTi(OEt)2(η1-C8H5O4)]. In particular, the novel developed half-titanocene catalyst exhibited more superior stability than representative half-titanocene complex, indicated by not only water compatibility for the employment of 30 % aqueous ethanol solution but also the recyclability that the products could be generated without apparent yield decrease after 5 runs. In general, we present a paradigm for sustainable molecular catalysis of titanocene.

Three Different Co(II) Metal–Organic Frameworks Based on 4,4′-Bis(imidazolyl)diphenyl Ether: Syntheses, Crystal Structure and Photocatalytic Properties

Three Co(II) metal–organic frameworks (Co-MOFs) build by 4,4′-bis(imidazolyl)diphenyl ether (bidpe), m-Phthalic acid (H2mpa), 5-Nitroisophthalic acid (H2nmpa) and 5-sulfonatobenzene-1,3-dicarboxylate (H2smpa), namely: [Co(mpa)(bidpe)]n (1), [Co(nmpa)(bidpe)]n (2), {[Co1.5(smpa)(bidpe)2]·1.5H2O·0.25DMA}n (3), were synthesized under same solvothermal condition. The compounds have been characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, thermogravimetric (TG) analysis and powder X-ray diffraction (PXRD). The single-crystal X-ray diffraction analysis reveals that compound 1 shows a 4-connected sql net with Schlafli point symbol (44·62). Compound 2 displays a 3, 5-connected net with Schlafli point symbol (42·67·8)(42·6). Compound 3 possesses a 3-connected net with Schlafli point symbol (42·6). The photocatalytic investigations indicate that compounds 1–3 afford good photocatalytic capabilities in degradation of methylene blue (MB) and methylene violet (MV). Furthermore, the possible photocatalytic mechanisms have been discussed.

Characterization of the solubility of m-phthalic acid in co-solvent mixture of acetone and ethanol at different temperatures

The solubility of m-phthalic acid has been measured in co-solvent mixtures conformed by acetone and ethanol over the entire solvent composition and in the temperature range of (278–323) K. Experimental results showed that the solubility always increased with increasing temperature in the binary solvent mixtures with constant solvent composition, indicating the endothermic character of the dissolution process. The solubility data was well correlated by semi-empirical regression models of the van't Hoff and the λh equations with average relative deviation (ARD) of 1.02% and 2.79%, respectively. Apparent deviation from the van't Hoff plot on solubility was observed but no polymorphic change of m-phthalic acid was found, implying the decisive influence of the change in the solvent molecular structure and the solvent-solvent interactions with temperature. On a solvent composition basis, the solubility in the co-solvent mixtures is clearly higher than that in both pure ethanol and acetone with the maximum appearing at acetone mole fraction in between 0.3 and 0.4, depending on the dipolarity/polarizability of the mixed solvents. On the other hand, m-phthalic acid exhibited reduced solubility when small amount of ethanol is added into acetone at temperatures above 315 K. The Simplified Modified Wilson (SMW) model was adopted to reproduce the isothermal solubility data over the entire acetone composition and the obtained overall ARD was 3.50%, with which the exact maximum solubility and the corresponding solvent composition at different temperatures were calculated.

Selective Host–Guest Co‐crystallization of Pyridine‐Functionalized Tetraphenylethylenes with Phthalic Acids and Multicolor Emission of the Co‐crystals

Tetraphenylethylene (TPE) and its derivatives are the most typical and most widely studied organic compounds showing aggregation-induced emission (AIE). Due to their propeller-like structures, V-like clefts exist between the aryl rings, which make them promising host compounds. However, such a possibility is seldom explored. Herein, it is reported that TPE derivatives bearing two or four pyridine rings at the para positions of the phenyl rings (TPE-Pys) can selectively include triangular (Δ-like) m-phthalic acid from a mixture of o-, m-, and p-phthalic acids due to their shape complementary to form host-guest co-crystals, which showed redder emission than the TPE-Pys themselves. The emission of co-crystals 1-5 could be reversibly switched between yellow and red by alternating exposure to HCl and ammonia vapor. The host-guest co-crystals not only exhibited great potential for selectively recognizing and separating m-phthalic acid and as multicolor emission materials, but are also suitable for use as secret ink due to their reversible color change on varying the host-guest interactions.

Determination of migrated phthalic acid residues into edible oils using a green mode of air-assisted liquid–liquid microextraction followed by high-performance liquid chromatography–diode array detector

In this study, for the first time, an organic solvent-free air-assisted liquid–liquid microextraction method has been reported for the extraction and preconcentration of phthalic acids (o-phthalic acid, m-phthalic acid, and p-phthalic acid) from edible oil samples. The method is based on the repeated aspirating/injection of an alkaline aqueous solution and the oil sample mixture in a conical bottom centrifuge tube to form a cloudy solution. After phase separation by centrifuging, the sedimented phase is directly analyzed by high-performance liquid chromatography–diode array detection. Under the optimum extraction conditions, the method showed low limits of detection and quantification between 0.11–0.29 and 0.28–0.91 ng mL−1, respectively. Extraction recoveries and enrichment factors were from 81 to 97% and 406 to 489, respectively. The relative standard deviations for the analysis of 5 ng mL−1 of each analyte were less than 5.9% for intraday (n = 6) and interday (n = 5) precisions. Finally, different oil samples were successfully analyzed using the proposed method and m-phthalic acid, and p-phthalic acid were determined in some of them at ng mL−1 level.

Hydrogen bonded supramolecular structures of eight organic salts based on 2,6-diaminopyridine, and organic acids

Here anhydrous and hydrated multi-component organic acid-base salts of 2,6-diaminopyridine have been prepared with the organic acids as trichloroacetic acid, 3,5-dinitrobenzoic acid, 5-nitrosalicylic acid, 3,5-dihydroxybenzoic acid, 5-sulfosalicylic acid, m-phthalic acid, naphthalene-1,5-disulfonic acid, and glutaric acid. The eight crystalline compounds were characterized by X-ray diffraction analysis, infrared (IR), melting point (mp), and elemental analysis. Except salt 4, all structures adopted the hetero R22(8) supramolecular synthon. There were extensive N–H···O/O–H···O/N–H···N/N–H···S hydrogen bonds as well as CH···O, CH–N, CH–π, NH–π, π–π, C–π, Cl–O, and O–O interactions in the supramolecular architectures. The combination of these weak and strong hydrogen bonding associations in the crystal packing led to the formation of the 2D/3D structures.

Seven supramolecular frameworks constructed from combination of hydrogen-bonds and other non-covalent associations between organic acids and bis-imidazoles

Seven crystalline organic acid–base adducts derived from bis(N-imidazolyl) and organic acids (2,4,6-trinitrophenol, p-nitrobenzoic acid, 3,5-dinitrobenzoic acid, oxalic acid, m-phthalic acid, and 1,5-naphthalenedisulfonic acid) were prepared and characterized by X-ray diffraction analysis, IR, mp, and elemental analysis. The seven compounds are all organic salts. In salts 1, and 3, the L1 are monoprotonated, while in 4 and 6 the L1 are diprotonated. All supramolecular architectures involve extensive classical hydrogen bonds and C–H⋯O interactions. The role of weak and strong non-covalent interactions in the crystal packing is analyzed. The complexes displayed 2D–3D framework structures for the synergistic effect of the various non-covalent interactions.The results presented herein indicate that the strength and directionality of the N–H⋯N, N–H⋯O, O–H⋯O, O–H⋯N, N–H⋯S, and O–H⋯S hydrogen bonds between the organic acids and the ditopic imidazoles are sufficient to bring about the formation of binary organic salts.

Syntheses, structures, thermal stabilities and photoluminescent properties of three silver(I) complexes of 2-ethyl-3-methylpyrazine and different aromatic dicarboxylates with various silver units

Three new silver(I) coordination compounds based on 2-ethyl-3-methylpyrazine (epyz), [Ag2(epyz)(pta] (1), [Ag4(epyz)2(ipa)2] (2) and [Ag8(epyz)4(npa)4] (3, H2pta=o-phthalic acid, H2ipa=m-phthalic acid, H2npa=1,4-napthalenedicarboxylic acid), have been synthesized and have been characterized by elemental analyses, IR spectra and single-crystal X-ray diffraction. Complex 1 shows a two-dimensional network comprising Ag2 units linked by the organic ligands. In complex 2, tetrahedral Ag4 units are bridged by the organic linkers into a double-layer structure. In complex 3, the chains with alternating Ag3 and Ag5 units are connected by the organic ligands into a three-dimensional framework. The structural diversity of these compounds and the Ag units is highly dependent on different carboxylates and the coordination modes of the epyz ligand. The thermal stabilities and photoluminescence behaviors of these complexes were also discussed.

Investigation into experimental conditions and factors for cyclohexane oxidation with VO(acac)2

The catalytic activity of VO(acac)2 for the cyclohexane(Cy) oxidation was studied. The effects of various parameters, such as the amounts of H2O2, HNO3, H2O and Cy were investigated. The highest total turnover number(TON) is 234, which can be increased to 353, 342 and 403, respectively with the adding of o-phthalic, m-phthalic or p-phthalic acid. A reaction mechanism was also supposed primarily.

A New Luminescent Cd(II) Coordination Polymer Based on 1,2,3-Triazole Controlled Double Helical Chain Subunits

A new Cd(II) coordination polymer, namely [Cd3(mbdc)(TZ)3(COO)(H2O)]n (1 H2mbdc = m-phthalic acid, TZ = 1, 2, 3-triazole), has been successfully synthesized under solvothermal conditions. Single-crystal X-ray analysis reveals that 1 features a two-dimensional (2D) layered structure based on 1,2,3-triazole controlled double helical chain subunits. Luminescent investigation shows that it emits strong fluorescence at room temperature in the solid state.

Synthesis, Structure, and Photoluminescent Property of a New In(III) Coordination Polymer Based on m-Phthalic Acid

A new luminescent coordination polymer, namely [HN(CH3)2]n[In(mbdc)2]n·n(DMA) (1 H2mbdc = m-phthalic acid, DMA = N, N′-Dimethylacetamide), has been successfully synthesized and structurally characterized. Single-crystal X-ray analysis reveals that 1 is a two-dimensional layered structure, which is further stacked into a three-dimensional supramolecular framework through intermolecular CH···π interactions.

Five new mononuclear complexes of 2-(5-methyl-1H-pyrazol-3-yl)pyridine: Synthesis, crystalline architectures through supramolecular interactions and spectroscopy

Five new mononuclear complexes with 2-(5-methyl-1H-pyrazol-3-yl)pyridine (L) have been synthesized, namely [ZnLCl2] (1), [NiL2(H2O)2)]Cl2·0.5N2H4 (2), [MnL2]·3H2O (3), [CdL2(NO3)2] (4) and [MnL2(Pa)2] (5, Pa=m-phthalic acid). All these compounds were characterized by elemental analysis, IR and UV–Vis spectroscopy, and X-ray single crystal diffraction. The crystal structures reveal that compounds 2, 3 and 5 afford six-coordinated octahedral spheres, whilst compound 1 displays a four-coordinated tetrahedral core and compound 4 forms an eight-coordinated geometry. Furthermore, the 3D supramolecular networks, formed through plentiful H-bonds and weak molecular interactions, have been analyzed. The photoluminescent properties of the ligand L, together with compounds 1 and 4, were also studied in methanol solution at room temperature.

Synthesis, characterization and crystal structure of one Co(II) complex with 4,4′-bisimidazolylbiphenyl and m-phthalic acid

One new title compound [Co(BIBP)(mpa)] n ( 1 ) (BIBP = 4,4′-biimidazole biphenyl, mpa = m-phthalic acid) has been synthesized under solvothermal condition. The title compound was characterized by IR spectra, thermal analysis, single crystal and powder X-ray diffraction. The results prove that the alliance of BIBP and aromatic carboxylic acids is good for diversity of the getatable structure. Magnetic susceptibility measurements indicate that compound 1 exhibits antiferromagnetic coupling between adjacent Co(II) ions. In addition, the photochemical properties have been investigated. One new title compound [Co(BIBP)(mpa)] n has been synthesized under solvothermal condition. Magnetic susceptibility measurements indicate that compound exhibits antiferromagnetic coupling between adjacent Co(II) ions. • A new Co coordination polymer with mixed-ligands has been synthesized. • The 2D framework was proven by single-crystal X-ray diffraction. • Title compound exhibits antiferromagnetic coupling between adjacent Co(II) ions.