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Excellent fluorescence properties are exhibited by d10 metal compounds. The novel three‐dimensional ZnII coordination framework, poly[[{μ2‐bis[4‐(2‐methyl‐1H‐imidazol‐1‐yl)phenyl] ether‐κ2N3:N3′}(μ2‐furan‐2,5‐dicarboxylato‐κ2O2:O5)zinc(II)] 1.76‐hydrate], {[Zn(C6H2O5)(C20H18N4O)]·1.76H2O}n, has been prepared and characterized using IR spectroscopy, elemental analysis and single‐crystal X‐ray diffraction. The crystal structure analysis revealed that the compound exhibits a novel fourfold interpenetrating diamond‐like network. This polymer also displays a strong fluorescence emission in the solid state at room temperature. [ABSTRACT FROM AUTHOR]

A novel three-dimensional 3d-4f metal-organic framework (MOF), {[(CH3)2NH2]2[Zn2Gd2(FDA)6(DMF)2]·2DMF}n (Zn-Gd) (H2FDA = furan-2,5-dicarboxylic acid) assembled with furan-2,5-dicarboxylic acid has been isolated and characterized by infrared spectra, elemental analysis, thermogravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction. Structure analysis indicates this MOF is an interesting three-dimensional 8-connected bcu body centered cubic topological net. Moreover, Zn-Gd MOF shows a tolerance towards moisture and the corresponding solvents, demonstrating the excellent chemical stability. The magnetic property of Zn-Gd MOF suggests a weak antiferromagnetic coupling interaction between adjacent Gd(III) ions in Zn-Gd MOF. [ABSTRACT FROM AUTHOR]

Abstract By adding K+, one-dimensional (1D) chain structure (1) can be converted into three-dimensional (3D) porous structure (BIPT-2). Two coordination polymers were characterized by single-crystal X-ray diffraction, powder X-ray diffraction, Thermogravimetric analyses, IR spectroscopy and fluorescence spectroscopy. Owing to its porosity, BIPT-2 shows excellent selectivity and sensitivity to diiodomethane than 1 through a strong fluorescence quenching. Graphical abstract By adding K+, one-dimensional (1D) chain structure (1) can be converted into three-dimensional (3D) porous structure (BIPT-2). Owing to the porous of BIPT-2 , it shows excellent selectivity and sensitivity to diiodomethane than 1 through a strong fluorescence quenching. fx1 Highlights • By adding K+ ions, one-dimensional chain structure (1) can be converted into three-dimensional porous structure (BIPT-2). • BIPT-2 possess 1D quadrangular channel with 3-interpenetration dia network. • Owing to the porous of BIPT-2 , it shows excellent selectivity and sensitivity to diiodomethane than 1 through a strong fluorescence quenching. [ABSTRACT FROM AUTHOR]

Two ZnII‐based coordination polymers (CPs) were synthesized by the hydrothermal method, using Zn(NO3)2·6H2O and furan‐2,5‐dicarboxylic acid (FDCA) in dimethylformamide (DMF) solvent, at 95 °C. Poly[tetrakis(dimethylazanium) [tetrakis(μ2‐furan‐2,5‐dicarboxylato‐κ2O2:O5)dizinc(II)]], {(C2H8N)4[Zn2(C6H2O5)4]}n or {[DMA]4[ZnII2(FDC)4]}n (DMA = dimethylazanium and FDC = furan‐2,5‐dicarboxylate), (1), was obtained with a 1:1 molar ratio of ZnII and FDCA. It crystallized in the monoclinic space group C2/c. Coordinated by ZnII ions, FDC2− ligands form 21 double‐stranded helices propagating along the b axis. The helices are interconnected and extend laterally in the a direction, forming a two‐dimensional (2D) sheet‐like network. The 2D sheets are stacked along the c direction without interconnections. DMA cations are cocrystallized in (1) and are hydrogen bonded with carboxylate O atoms of the FDC2− ligands. The hydrogen‐bonding pattern consists of R22(4) and R22(10) motifs alternating in a chain. Poly[bis(dimethylazanium) [bis(μ4‐furan‐2,5‐dicarboxylato‐κO2:κO2′:κO5:κO5)bis(μ3‐furan‐2,5‐dicarboxylato‐κO2:κO2′:κO5)dizinc(II)] dimethylformamide 3.08‐solvate], {(C2H8N)2[Zn2(C6H2O5)4]·3.08C3H7NO}n or {[DMA]2[ZnII3(FDC)4]·3.08DMF}n, (2), was obtained with a 1:2 molar ratio of ZnII and FDCA. It crystallized in the monoclinic space group P21/c, forming a three‐dimensional network. The pores are filled with DMA cations and DMF solvent molecules. Two ZnII‐based coordination polymers were synthesized by the hydrothermal method, using Zn(NO3)2·6H2O and furan‐2,5‐dicarboxylic acid, one polymer exhibiting two‐dimensional networks consisted of 21 double‐stranded helices and the other a three‐dimensional network, with the pores filled with cations and solvent molecules. [ABSTRACT FROM AUTHOR]

Furan‐2,5‐dicarboxylic acid (FDCA) has been ranked among the top 12 bio‐based building‐block chemicals by the Department of Energy in the US. The molecule was first synthesized in 1876, but large‐scale production has only become possible since the development of modern bio‐ and chemical catalysis techniques. The structures of two FDCA solvates, namely, FDCA dimethylformamide (DMF) disolvate, C6H4O5·2C3H7NO, (I), and FDCA dimethyl sulfoxide (DMSO) monosolvate, C6H4O5·C2H6OS, (II), are reported. Solvate (I) crystallizes in the orthorhombic Pbcn space group and solvate (II) crystallizes in the monoclinic P space group. In (I), hydrogen bonds form between the carbonyl O atom in DMF and a hydroxy H atom in FDCA. Whilst in (II), the O atom in one DMSO molecule hydrogen bonds with hydroxy H atoms in two FDCA molecules. Combined with intermolecular S…O interactions, FDCA molecules form a two‐dimensional network coordinated by DMSO. [ABSTRACT FROM AUTHOR]

Two isostructural lanthanide MOFs, [Ln 3 K 2 (FDA) 4 (NO 3 ) 3 (MeCN) 2 ] n (Ln = Eu 1 , Tb 2 ) (H 2 FDA= furan-2,5-dicarboxylic acid), have been constructed under solvothermal conditions. Structures analyses demonstrate two complexes possess three-dimensional network with monoclinic space group C2/c . The topology analysis shows that the whole framework can be simplified to a 3,8T24 topology constructed from trinuclear {Ln 3 } as secondary building units (SBUs) without considering K + ions. Solid state luminescent studies indicate that 1 and 2 show the characteristic red and green emissions of the corresponding Ln 3+ ions, respectively. The luminescence lifetimes of 1 and 2 are approximately 1.04 ms and 0.41 ms. In addition, activated 1 exhibits excellent fluorescence sensing for small molecules, especially for nitrobenzene. [ABSTRACT FROM AUTHOR]

A rare lanthanide metal-organic framework (Ln-MOFs) based on Nd(III) binuclear nodes, with formula {[Nd 2 (H 2 O) 3 (FDA) 3 (CH 3 OH)]⋅ CH 3 OH} n ( 1 ) (H 2 FDA = furan-2,5-dicarboxylic acid), was obtained under solvothermal conditions and characterized by single crystal X-ray diffraction, thermogravimetric analysis and luminescent measurements. 1 has two type of Nd 2 binuclear clusters stabilized by carboxylic groups and exhibits a new topology structure. It is a four nodes 3,3,5,6-connected net with the point symbols of (4.5.6) 2 (4.6 2 ) 2 (4 2 .5 4 .6 2 .7 2 ) 2 (5 2 .6 6 .7 4 .9 2 .10). Moreover, the near-infrared (NIR) luminescence of 1 based on Nd(III) and H 2 FDA were investigated in the solid state at room temperature for the first time. [ABSTRACT FROM AUTHOR]

Two new lanthanide metal–organic frameworks (Ln-MOFs) based on Dy(III) binuclear nodes, with formulas {[NH 2 (CH 3 ) 2 ][Dy 2 (FDA) 3 (NO 3 )]·CH 2 Cl 2 ·H 2 O} n ( 1 ) and [Dy 2 (FDA) 2 (ox)(glycol) 2 ] n ( 2 ) (H 2 FDA = furan-2,5-dicarboxylic acid), are synthesized and structurally characterized. The building blocks of two MOFs are both binuclear clusters stabilized by carboxylic groups, but the architectures are different. MOF 1 is a rare 3,9-connected FEZNUU net with point symbol of (4.6 2 )(4 10 .6 17 .8 9 )(4 3 ), whereas MOF 2 exhibits a new topology, in which a four nodes 4,4,5,5-connected net with the point symbols of (4 3 .5 2 .6)(4 3 .5 3 .6 2 .7 2 ), respectively. Moreover, luminescence investigation of 1 and 2 shows intense and characteristic emission bands of Dy(III) ions in the solid state. [ABSTRACT FROM AUTHOR]

ABSTRACT Furan-2,5-dicarboxylic acid (FDCA) is a widely advocated renewable substitute for terephthalic acid (TA). Preparation of high molecular weight FDCA based polyesters by an industrially common combination of melt polymerization and subsequent solid state post condensation is described. Ultimately, poly(ethylene 2,5-furanoate) (PEF) with absolute Mn = 83,000 g mol−1 is obtained, determined by triple detection Size Exclusion Chromatography. The bulk polymer properties of FDCA based polyesters, necessary to evaluate their industrial potential were determined the Young's modulus of PEF is determined to be 2450 ± 220 MPa and the maximum stress 35 ± 8 MPa. The influence of crystallinity on the mechanical properties as function of temperature was determined by dynamic mechanical thermal analysis. A detailed differential scanning calorimetry study on the crystallization behavior of high molecular weight PEF allowed to calculate the equilibrium melting temperature ( Tm0) of 239.3 and 239.7 °C for the first and second melting peak, respectively. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4191-4199 [ABSTRACT FROM AUTHOR]

A short and effective method for preparation and isolation of furan-2,5-dicarboxylic acid has been developed. Furan-2,5-dicarboxylic acid was prepared directly from furan-2-carboxylic acid in one step under strong basic conditions using carbon dioxide. This method allows to obtain the product with high added value, furan-2,5-dicarboxylic acid, from natural sources such as hemicelluloses containing pentoses. [ABSTRACT FROM AUTHOR]

[Display omitted] • Six enzymes were tested for the conversion of HMF and its oxidation products. • A Michaelis-Menten kinetic model was constructed based on experimental results. • The model was in good agreement with single-enzyme reactions. • Multi-enzyme reactions with two to four enzymes were used for model validation. Six enzymes were tested against HMF and its oxidation intermediates to determine substrate specificity, product yield and pathways. A Michaelis–Menten kinetic mathematical model was constructed and some rate parameters calculated. The best 2,5-diformylfuran (DFF) productivity was obtained with alcohol oxidase (AO) and 10.0 mM HMF, where 3.0 mM DFF was formed, followed by galactose oxidase (GO) and 10.0 mM HMF with a 0.5 mM DFF yield. Oxygen concentration in solution remained unchanged during processes. Substrate concentration affected only AO, where around 10 mol.% more DFF was formed with 5.0 mM HMF. The model was mostly in good agreement with single-enzyme reactions. Multi-enzyme reactions were used for model validation. The combination of AO and catalase was optimal, converting 10.0 mM HMF to 9.7 mM DFF. Small discrepancy between measured and modeled multi-enzyme reactions was observed due to the exclusion of the specific interactions in mechanisms. [ABSTRACT FROM AUTHOR]

Furan-2,5-dicarboxylic acid (FDCA) is a building block of biodegradable plastics that can be used to replace those derived from fossil carbon sources. In recent years, much interest has focused on the synthesis of FDCA from the bio-based 5-hydroxymethylfurfural (HMF) through a cascade of enzyme reactions. Aryl-alcohol oxidase (AAO) and 5-hydroxymethylfurfural oxidase (HMFO) are glucose-methanol-choline flavoenzymes that may be used to produce FDCA from HMF through three sequential oxidations, and without the assistance of auxiliary enzymes. Such a challenging process is dependent on the degree of hydration of the original aldehyde groups and of those formed, the rate-limiting step lying in the final oxidation of the intermediate 5-formyl-furancarboxylic acid (FFCA) to FDCA. While HMFO accepts FFCA as a final substrate in the HMF reaction pathway, AAO is virtually incapable of oxidizing it. Here, we have engineered AAO to perform the stepwise oxidation of HMF to FDCA through its structural alignment with HMFO and directed evolution. With a 3-fold enhanced catalytic efficiency for HMF and a 6-fold improvement in overall conversion, this evolved AAO is a promising point of departure for further engineering aimed at generating an efficient biocatalyst to synthesize FDCA from HMF. • The synthesis of FDCA from biomass-derived HMF is arising a great interest for bio-based industries. • This study provides proof-of-concept of an AAO engineered by directed evolution for the synthesis of FDCA from HMF. [ABSTRACT FROM AUTHOR]