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A novel methodology for the decarboxylative Suzuki–Miyaura-type coupling has been established. This process uses iodine or a bromine source as both the decarboxylation mediator and the terminal oxidant, thus avoiding the need for stoichiometric amounts of transition metal salts previously required. Our new protocol allows for the construction of valuable biaryl architectures through the coupling of (hetero)aromatic carboxylic acids with arylboronic acids. The scope of this decarboxylative Suzuki reaction has been greatly diversified, allowing for previously inaccessible non-ortho-substituted aromatic acids to undergo this transformation. The procedure also benefits from low catalyst loadings and the absence of stoichiometric transition metal additives. [ABSTRACT FROM AUTHOR]

Abstract: 2-((4-Methoxyphenoxy) carbonyl) benzoic acid, 2-(1-methoxyvinyl) benzoic acid and their rare earth complexes LnL2(OH)·3H2O (Ln=La, Eu, Tb) were synthesized and characterized by means of elemental analysis, FTIR, 1H NMR, UV and luminescence spectroscopy. The FTIR and 1H NMR results show that the carboxylic groups in the complexes coordinated to the rare earth ions in the form of one dentate, and the ester carboxylic groups have taken part in the coordination. Among these complexes, Eu(III) complexes and Tb(III) complexes exhibit characteristic fluorescence with comparatively high brightness and good monochromaticity, which indicated that the ligands of HLI and HLII are good organic chromophore to absorb and transfer energy to metal ions. [Copyright &y& Elsevier]

(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. [ABSTRACT FROM AUTHOR]

Polymethyl acrylic acid (PMAAc) with lower molecular weight was prepared by solution polymerization in water. A series of macromolecular rare earth complexes of PMAAc (RE-PMAAc, RE=La,Sm,Eu,Tb,Dy) have been synthesized and well characterized by means of elemental analysis, IR, TG-DTA analyses and fluorescence determination. Chemical analysis indicated that the molar ratio of -COO- and RE3+ in the complex was closely dependent on the pH of the solution. Spectroscopic studies suggested that the carboxylate was bonded to the central metal ions in bidentate form and these macromolecular complexes were cross-linked with high-temperature resistance. Among these complexes, Eu-PMAAc, Tb-PMAAc and Dy-PMAAc solid complexes are excellent photoluminescence materials, which can emit high intensity and good monochromatic characteristic fluorescence due to an effective energy transfer between the lowest excited triplet state energy level of ligand PMAAc and the excited state energy level of the corresponding rare earth ion. [ABSTRACT FROM AUTHOR]

In this study, four functional β-cyclodextrin derivatives including amidoxime linear-linked and cross-linked β-cyclodextrin/acrylonitrile/acrylic terpolymer (l-CD-AO-AA and c-CD-AO-AA), citric acid cross-linked poly-β-cyclodextrin (PCD), amidoxime cross-linked β-cyclodextrin and acrylonitrile–acrylic block copolymer (CD-b-AO-AA) were synthesized and properties of β-CD derivatives were characterized by FT-IR, SEM, TGA and element analysis. The effect of solid liquid ratio of the adsorbents, ionic strength, pH, contact time, initial concentration of U(VI), adsorption temperature, selective adsorption for different metal ions and the reasonable desorption conditions were studied. It was found when content of U(VI) was 22 mg/L, the four functional materials l-CD-AO-AA, c-CD-AO-AA, PCD and CD-AO-b-AA completely adsorbed U(VI) at 0.06 g/L (R ≈ 97%), 0.10 g/L (R ≈ 96%), 0.08 g/L (R ≈ 94%) and 0.52 g/L (R ≈ 94%), respectively. [ABSTRACT FROM AUTHOR]