Beta-diketone complexes

Champmartin D and Rubini P 1996 Determination of the 0-17 quadrupolar coupling constant and of the C-13 chemical shielding tensor anisotropy of the CO groups of pentane-2,4-dione and beta-diketonate complexes in solution. NMR relaxation study/norg. Chem. 35 179-83... 

Strontium titanate (SrXi03) by reacting titanium isopropoxide and a strontium beta-diketonate complex at 600-850°C and 5 Xorr. 

Strontium titanate (SrTi03) has a large dielectric constant of 12, and a high refractive index with potential opto-electronic applications. It is deposited by MOCVD from titanium isopropoxide and a strontium beta-diketonate complex at 600-850°C and 5 Torr.t" " ... 

Otway DJ, Rees WS (2000) Group 2 element beta-diketonate complexes, synthetic and structural investigations. Coordination Chemistry Reviews 210, 279-328... 

It is a commonplace to say that there has been explosive growth in the use of lanthanides in organic chemistry. For many years, the use of cerium(iv) compounds as oxidants was widespread, but more recently a whole range of other compounds have made their appearance. Thus samarium(ii) compounds are now routinely used as one-electron reducing agents and the use of trifluoromethanesulfonate ( triflate ) salts of scandium and the lanthanides as water-soluble Lewis acid catalysts is widespread. Beta-diketonate complexes and alkoxides have also come into use there are even applications of mischmetal in organic synthesis. 

Fraas, R. E. Ionic Fragmentation Processes of Beta-Diketonate Complexes of the Group III Metals, Doctoral Dissertation, University of Kentucky, Lexington, Kentucky, 1972. 221 pp. (Order no. 73- 7,343, University Microfilms, Ann Arbor, Mich.)... 

Villata, L. S. Wolcan, E. Feliz, M. R. Capparelli, A. L. Competition between intraligand triplet excited state and LMCT on the thermal quenching in beta-diketonate complexes of europium(III). J. Phys. Chem. A 1999, 103, 5661 5666. 

Turning now to the more tightly bound filled orbitals we examine the evidence from photoelectron spectroscopy. By comparing the ultra-violet excited photoelectron spectrum (UPES) of volatile uranyl beta-diketonate complexes [45] with the spectrum of complexes of the same ligands with other metals, two sharp ionisations are observed, at 10.30 and 10.80 eV, which. seem to be assignable to uranyl-oxygen ionisations. The lower of these ionisations increases in relative... 

Y. Akiyama, T. Sato and N. Imaishi, Reaction Analysis for Z1O2 and Y2O3 Thin-Film Growth by Low-Pressure Metalorganic Chemical-Vapor-Deposition Using Beta-Diketonate Complexes, J. Cryst. Growth, 147, 130-146(1995). 

Metal-complexation/SFE using carbon dioxide has been successfully demonstrated for removal of lanthanides, actinides and various other fission products from solids and liquids (8-18), Direct dissolution of recalcitrant uranium oxides using nitric acid and metal-complexing agents in supercritical fluid carbon dioxide has also been reported (79-25). In this paper we explored supercritical fluid extraction of sorbed plutonium and americium from soil using common organophosphorus and beta-diketone complexants. We also qualitatively characterize actinide sorption to various soil fractions via use of sequential chemical extraction techniques. 

Nockemann P, Beurer E, Driesen K, Van Deun R, Van Hecke K, Van Meervelt L, Binnemans K (2005) Photostability of a highly luminescent europium [small beta]-diketonate complex in imidazolium ionic liquids. Chem Commun 34 4354-4356... 

Martin-Ramos P, Silva MR, Coya C, Zaldo C, Alvarez AL, Alvarez-Garcia S, Matos Beja AM, Martin-Gil J (2013) Novel erbium(iii) fluorinated [small beta]-diketonate complexes with N, N-donors for optoelectronics from synthesis to solution-processed devices. J Mater Chem C 1 (15) 2725-2734... 

Triphenylformazan behaves as a bidentate ligand forming 2 1 complexes (217) with divalent copper, nickel, and cobalt.377 Formazan metal complexes can be compared to complexes of azo dyes or beta diketones due to structural similarity.301,302 In general, formazan metal complexes have low stability toward acids. However, when electron-donating substituents are added to the aromatic ring, a considerable enhancement in stability is observed. Cationic complexes of type 218 are also known. The complexation of formazan with metal cation can be accompanied by oxidation to the tetrazolium salt and the formation of a complex... 

Chelating extractants such as beta-diketones, tropolones, hydroxyoximes, and 8-hydroxyquinolines (Figure 2.1), have been used extensively for the extraction of actinide ions from moderate to weakly acidic solutions (15-17). Beta-diketones such as acetylacetone (acac), HTTA, benzoyl trifluoroacetone (BTFA), and dibenzoyl-methane (HDBM) have been commonly used for the separation of actinide ions. The extraction mechanism involved formation of the enol form of the beta-diketone prior to complexation and extraction of the metal ion (Figure 2.2). 

Manchanda, V.K. Subramanian, M.S. Infrared and P.M.R. investigations of some complexes of uranyl beta diketonates with methyl substituted pyridine N-oxides, Aust. J. Chem. 27 (1974) 1573-1577. 

Complex compounds Beta diketones, CO, A1C13 Fused silica, glass... 

The fourth chapter deals with complexes of rare earth elements with a variety of complexing agents, such as monocarboxylic acids, dicarboxylic acids, polycarboxylic acids like citric, nitrilotriacetic, ethylenediamine tetraacetic beta diketones, ligands with... 

He, H., Sykes, A.G., Galipeau, D., et al. (2008) Crystallography and photoluminescence properties of beta-diketonate monoporphyrinate ytterbium(III) complexes. Inorganic Chemical Communications, 11, 1051. 

Metal chelates containing beta-diketonate ligands have been used for a variety of purposes, including gas chromatography of metals,1 metal plating on surfaces,2 solvent extraction of metals,3 5 catalysts, and fuel additives.6-7 The physical properties of these complexes that determine their usefulness in these areas are thermal stability, volatility, and solubility in nonpolar solvents. 

The crude H(tod) is purified first by vacuum distillation (1 torr, 60-90°) to separate the ligand from high boiling but organic-soluble impurities. Second, the copper complex is synthesized, as described below, to isolate the beta-diketone from any by-products that are formed by self-condensation of the ketone. Crude [Cu(tod)2] (20 g) is placed in a 250-mL separatory funnel with 30 mL of hexane and 150 mL of 10% (1 M) aqueous sulfuric acid. The mixture is shaken until no blue color remains in the organic phase. The organic solution is isolated and the solvent is removed by rotary evaporation. Generally, the H(tod) product is 97-99% pure. 

The Cu(tod)2 is much more soluble in hexane than almost all previously reported copper beta-diketonates.3 The logarithm of the partition coefficient of Cu(tod)2 between 1-octanol and water (log Poe,) is 3.64 0.20. This value, which is unusually large for a metal complex, is an indication of the expected bioavailability9 of [Cu(tod)2]. We have shown that a 50% (v/v) solution of H(tod) in kerosene is capable of extracting copper(II) ion from ammoniacal aqueous solutions in high yield, which may be useful for commercial recovery of copper from ore leachates.5... 

The major breakthrough that transformed metal chelate GC into a useful analytical technique was the introduction of fluorinated beta-diketone ligands, which formed complexes of greater volatility and thermal stability. Trifluoroacetylacetone (l,l,l-trifluoro-2,4-pentanedione—HTFA) and hexafluoro-acetylacetone (l,l,l,5,5,5-hexafluoro-2,4,-pentanedione—HHFA) are the fluorinated ligands most frequently employed. HTFA extended the range of metals that may be gas chromatographed with little or no evidence of decomposition to include Ga3+, In3+, Sc3+, Rh3+ and V4+. An example of a recent application is the analysis for beryllium in ambient air particulates. After filter sampling and extraction/chelation, packed column GC with electron capture detection allowed ppm level beryllium quantitation in collected particulates which corresponded to levels of 2-20 x 10 5 pg/m3 in the sampled air. 

Wataiai H, Ogawa K, Suzuki N (1993) Formation of fluorescent complexes of Eu(lll) and Sm(lll) with [beta]-diketones and trioctylphosphine oxide in oil-water microemulsions. Anal Chim Acta 277 73-78... 

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